EOI LAB MANUAL
TEACHERS EDITION
1
2
Lesson
overview page
Index
Lab page
How to use this document
Process and Content Skills
Writing in the science curriculum
4
1) Characteristics of living things
9
11
2) Cell Theory
13
15
3) Mitosis and Cell Division
19
21
4) Osmosis and Diffusion
25
27
5) Enzyme activity
30
32
6) Calorie Measurement
37
39
7) Cellular Respiration
41
43
8) Photosynthesis
48
50
9) Karyotyping and Chromosome Theory
52
53
10) DNA Extraction From Cheek Cells
57
58
11) Probability
59
61
12) Genetics of Masa
64
66
13) Human Genetic Traits
70
72
14) Variation within a population
76
78
15) Population Genetics
80
82
16) Classification and Phylogeny
86
87
17) Plant Transpiration
96
98
18) Primary productivity
102
104
19) Population growth
107
109
20) Animal behavior
112
114
7
3
HOW TO USE THIS DOCUMENT
PROCESS SKILL DEVELOPMENT
The following lab materials were created to meet the requirements of students taking the
Oklahoma End of Instruction test at the end of Biology I. The labs are designed to integrate
national teaching standards, PASS skills, research based pedagogy and the needs of both block
scheduling and the traditional six-hour schedule. We specifically pursued activities that would
require a minimum of resources and out of pocket expense.
Our students enter ninth grade with a wide range of language and math skills. When the
students try to make sense of the material in biology they use both their prior experience and the
first-hand knowledge gained from explorations in class. Because of the breadth of prior
knowledge among our students, we have to assume that as a group, they may know very little
about DNA, chromosomes, cells or solving three step problems. To help overcome the disparity
of prior knowledge we have adopted the BSCS curriculum model of the Five Es (Engage,
Explore, Explain, Elaborate and Evaluate). The learning cycle model utilized by the Five Es
allows every student to begin with fundamental concepts that serve as the basis for making sense
out of a discipline as wide as biology. An easy way to look at the Five Es is that students perform
the lab first then the reading and supplementary materials reinforce the learning experience.
Students can only learn if they know what we are talking about!
The lesson model employing the Five Es is as follows;
Engage. During the engage stage the students first identify and encounter an instructional task.
These are often demonstrations to provide a concrete example of a principle or idea. This is the
place to make connections with prior knowledge and present learning goals. Asking questions
such as “What are the characteristics of life?”, “How do genes work?”, “Why do whales have
finger bones?” are ways to engage students and focus them on instructional events. This is the
place for a demonstration that models the relationships that students should understand.
Explore. During the explore part of the lesson students work directly with a manipulative to gain
understanding of a principle. Exploration is where students learn to measure and quantify. As
they work together in teams, students build a base of common experience which assists them in
the process of sharing and communicating. The instructor acts as a facilitator to guide focus and
direction. The students inquiry process drives the instruction during exploration.
Explain. The explain phase integrates the text(s), or uses the information provided in the lab.
Communications occur between peers, the facilitator, the text, or within the learner himself.
Working in groups, the learners support each other’s understanding as they articulate their
observations, ideas, questions and hypotheses.
Extend. This section allows the students the opportunity use their newly aquired knowledge,
expand and solidify understanding by designing applications of the concept to real world
situations. The students use skills developed during the previous three stages to develop and
implement an investigation. They design the investigation, collect data and perform the analysis.
Evaluate. The students either enter summaries of their learning in journals, or present findings to
the class. One of the most powerful tools that a teacher has is evaluation. “How do you know
that?” When students write about their experiences they have to integrate higher order thinking
skills to make a summation. The evaluation phase enters the information into long-term memory.
4
If the students present their findings, the information allows for further inquiries and a way to
easily measure learning.
The nationals teaching standards for the use of inquiry are integrated into this document
by utilizing the learning cycle, and the use of labs and investigations at for at least half of the
instructional time. The inquiry style is “guided inquiry” which provides a structured classroom
environment and the efficient use of limited resources.
Table #1. Essential features of Classroom Inquiry and Their Variations
Variations
Essential
Feature
1. Learner engages in
scientifically oriented
questions
Learner poses a
question
Learner selects
among questions,
poses new
questions
2. Learner gives
priority to evidence
in responding to
questions
Learner
determines what
constitutes
evidence and
collects it
Learner
formulates
explanation after
summarizing
evidence
Learner
independently
examines other
resources and
forms the links
to explanations
Learner forms
reasonable and
logical argument
to communicate
explanations
Learner directed
to collect certain
data
3. Learner formulates
explanations from
evidence
4. Learner connects
explanations to
scientific knowledge
5. Learner
communicates and
justifies explanations
Learner sharpens
of clarifies
question provided
by teacher,
materials, or other
source
Learner given data
and asked to
analyze
Learner engages in
question provided
by teacher,
materials, or other
source
Learner guided
in process of
formulating
explanations
from evidence
Learner directed
toward areas and
sources of
scientific
knowledge
Learner given
possible ways to
use evidence to
formulate
explanation
Learner given
possible
connections
Learner provided
with evidence
Learner coached
in development
of
communication
Learner provided
broad guidelines to
use shaping
communication
Learner given
steps and
procedures for
cummunication
Learner given data
and told how to
analyze
More---------------------------Amount of Learner Self-Direction---------------------Less
Less---------------------Amount of Direction from Teacher of Material------------More
From Inquiry and the National Science Education Standards
National Research Council, 2000
5
CONTENT SKILL DEVELOPMENT
The material covered follows the fundamental themes of biology. The big ideas that permeate
this document are;
Cells
Living things are made of cells
All cells come from pre-existing cells
Cells are the structural/functional units of life
Chromosomes
Chromosomes occur in pairs
Genes are located on chromosomes
Chromosome number is species specific
Genetics
Alleles occur in pairs
Dominant alleles mask recessive alleles
There is an equal chance of either parental allele occurring in a gamete
Phenotypes are determined by genotypes and the environment
Evolution
Variation occurs in populations
Populations over-reproduce
Survivors pass traits to offspring
Populations
Populations share a common gene pool
The environment selects successful phenotypes
Populations are the units of evolution
Classification
Organisms with similar traits are closely related
Similar organisms have similar genes and DNA
Ecology
Materials are recycled, energy is lost as heat
90% of the energy is lost at each trophic level
Energy is located in molecular bonds
Communities have inter and intraspecific competition.
PASS Skill Correlations
The lab manual was designed to correlate closely with the Oklahoma State Department of
Education PASS skills. At the end of instruction
6
DEVELOPING READING AND WRITING SKILLS
So, What About Reading?
Research in the area of reading skills development offers many suggestions for teachers to help
students read more effectively.
First thing is to always integrate reading into every lesson. Reading must be an integral part of
the learning process just as it is an integral part of everyday life.
A common weakness in student reading skills at the high school level is in the area of reading
comprehension, or the students’ ability to thoroughly understanding what they read. This
problem is magnified greatly in science because of the high reading levels and difficult
vocabulary within the science fields. Remember, most science terminology is based on foreign
languages (mostly Greek and Latin).
Here are some suggestions to help students with reading and comprehension skills in the science
class:
 Discussion Groups: very minimal comprehension takes place when students read from a
book and never have the opportunity to communicate what they have read. Student
discussion groups are very effective ways to give students the opportunity to discuss what
they have read. Research suggests that if students talk about what they have read
immediately following the reading it will greatly increase the students’ comprehension.
So, assign a reading passage to a small group of students, give them time to read it and
then give them time to discuss the reading content.
 Writing Process: another way students can communicate what they have read is through
the writing process. There are many effective ways to get students to write about what
they read. Some examples of effective writing strategies include the use of writing
journals and open-ended questions that require students to write short answers to
questions directly linked to the reading assignment.
 Don’t Over Do It! Don’t overwhelm students with non-essential reading. When
conducting the labs in this manual, the students should read text or other pertinent
information that relates to a specific lab. Do not expect high levels of comprehension if
other activities to not relate to the required reading.
 Use Graphic Organizers: graphic organizers and concept maps are valuable tools that
help students comprehend reading, especially what the required reading is full of detail
and complex vocabulary.
 Use Inquiry When Reading: getting students to ask questions is always beneficial in the
reading process. This can be helpful both before and after reading assignments. Ask
students to form questions about the reading prior to or after the reading is completed.
Students can also quiz each other about the reading in small groups. This gives them the
opportunity to discuss the reading and possibly have some fun doing with their peers!
7
SAMPLE SCIENCE LABORATORY WRITE-UP
An outline for lab reports is presented below. Students are expected to write a clear description
of procedures and what was learned. A strong data-graph section and conclusion are needed for a
paper to meet the standard.
TITLE OF EXPERIMENT
PROBLEM STATEMENT
HYPOTHESIS
MATERIALS
PROCEDURE
DATA/OBSERVATIONS
CALCULATIONS
GRAPHS
THE THREE-PART
CONCLUSION SECTION
PART ONE
PART TWO
PART THREE
What should the experiment be called?
Describe briefly, in your own words, the main purpose
of the experiment.
Using logic/reason, predict an outcome using the “If,
and, then” format.
List all essential materials and apparatus needed for the
investigation.
Describe briefly, in your own word, the procedure.
Usually 5 or 6 steps.
Show all quantitative data in appropriate charts. Show
qualitative data with clear labels. Drawings should be
large and easy to see.
Show a sample of each type of calculation with the
result circled or boxed
Show all required graphs and data transformations.
Graphs must have descriptive title, have the X and Y
axis clearly labeled with units and ranges.
This part is designed to allow reflection and review of
the investigation and results. It pulls the educational
purpose of the lab together.
WHAT YOU DID
Restate the purpose and goals (objectives) of the lab.
Restate the original hypothesis and indicate how the
investigation relates to what is being studied in class.
WHAT YOU SAW
Discuss the data collected during the investigation.
Make numerical comparisons using significant figures.
“Respiration rates increased by 23% during the night.”
This is the “How much” section.
WHAT IT MEANS
Use the observed data to support or refute reasonable
conclusions. Accept of reject and stated hypothesis
using the observed data as supportive evidence.
8
LAB EVALUATION RUBRIC
This is a model rubric that teachers can modify to fit their classes and needs.
SKILL
1
HYPOTHESIS
DESIGN
Clearly stated
before class
If-then format
Has protocol
prepared
before data
collection
begins
Single trial
Protocol in
own words
Multiple
trials, control
Multiple trials,
control, single
variable
Tables
prepared prior
to data
collection
Tables
prepared
prior to data
collection,
data entered
Purpose
restated and
data
collection
discussed,
questions
answered
Prepared
tables, data
collections.
Graphs
prepared
Purpose
restated, data
discussed,
hypothesis
evaluated,
questions
answered
Contributed
to design and
played a
specific role
Consistantly
contributed in
all aspects of
investigation
DATA
COLLECTION
DATA
TABLES/GRAPHS
EVALUATION
TEAMWORK
SKILL LEVEL
2
3
Lab purpose
restated,
questions
answered
Contributed
to laboratory
If-then
statement with
variables
Protocol in
own words
and in
sequence
SCORE
4
Quantified ifthen statement
with variable
Protocol in
own words,
proper
sequence and
concise.
Multiple trials,
control, single
variable,
overcame
obstacles
Prepared
tables, graphs,
and examples
of data
calculations
Purpose
restated, data
discussed,
reasonable
conclusion
reached,
questions
answered.
Input/output
consistent,
stayed with
group
throughout,
respected
others and
worked to
completion.
TOTAL
9
LAB #1, CHARACTERISTICS OF LIVING THINGS
LESSON OVERVIEW
The “Characteristics of Living Things” reviews and introduces the students to the main
themes of biological science; All organisms are made of cells, organisms exchange materials
with the environment, organisms reproduce, organisms grow and develop, organisms are
organized, an organisms’ traits are determined by nucleic acids, organisms use energy.
STRAND
Cells are the structural/functional units of life.
OBJECTIVES After this lesson the student will be able to:
1) Define biotic, abiotic, hierarchy, organism, organ system, tissue, organ, cell.
2) Observe and qualify the characteristics of living organisms.
3) Compare differences between animate and inanimate objects.
PASS SKILLS ADDRESSED
P2.1 Using observable properties, place cells, organisms, and/or events into a biological
Classification system.
P2.2 Identify the properties by which a biological classification system is based.
1.2 Cells can differentiate and may develop into complex multicellular organisms (i.e., cells,
tissues, organs, organ systems, organisms).
MATERIALS AND PREPARATION
Set up eight to ten stations with examples of organisms, microscopes, etc. Examples;
germinating and non-germinating beans, fossil, lichen, rollie-pollie, burning butter or
marshmallow, algae, prepared slides of bacteria, milk, wood block, mushroom, yogurt, soil,
earthworms, etc. A good sample for the group to test is a yeast suspension. Give each group an
overhead sheet and five minutes to present findings and conclusions. On the sheet should be their
question, hypothesis, test results and conclusions. Allow the students to answer questions from
the class. Presenting, summarizing, and evaluating will place the concepts into long-term
memory
LESSON SEQUENCE
1) The instructor should engage the students by asking them what they know about the
characteristics of living things. The student generated criteria should be posted on the
board or overhead during the entire lesson.
2) Students observe samples and quantify their observations.
3) Class summarizes findings and generates criteria for characteristics of life.
4) Lab groups collect data on unknown.
5) Lab groups present findings to the class and reevaluate the criteria.
6) Students enter findings or summaries in lab books or journals.
10
LAB #1, THE CHARACTERISTICS OF LIVING THINGS
OBJECTIVES, After this lab the student will be able to;
1) Define biotic, abiotic, hierarchy, organism, organ system, tissue, organ, cell.
2) Observe and qualify the characteristics of living organisms.
3) Compare differences between animate and inanimate objects.
EXPLORE
Visit each of the ten stations and examine a specimen. Describe the specimen and list the
obvious characteristics on the data table. As you observe the specimen ask yourself which
observable criteria of life are present, and think of tests that you could perform to determine if
the object is alive, was once alive, is dormant, was produced by a living organism, or is just a
complex chemical reaction.
DATA
For each object, name it and note the observable characteristics of life that it possesses,
use the life categories below to characterize the specimen, and describe any tests that could be
performed to test if the organism is (was) alive. Record your results in Table #1.
Table #1. Characteristics of Animate and Inanimate Objects.
#
Name
Characteristics
Categories
Tests
1
2
3
4
5
6
7
8
Categories: 1) Alive, 2) Alive but dormant, 3) Dead (once alive), 4) Product of a living organism, 5) Never alive.
EXPLAIN
We are surrounded by living things. Our question today is, “What characteristics do all living
things share? What makes something alive?” The classic definition of living things includes the
following criteria; 1) All living things are made of cells. 2) All living things respond to their
environment. 3) All living things reproduce. 4) All living things grow and develop. 5) The
expression of traits in living things is controlled by a nucleic acid. 6) All living things are
organized. 7) All living things use energy to perform work.
11
EXTEND
The instructor will provide a specimen to your group. You are to generate a hypothesis as to the
whether the specimen is alive then collect evidence for any three of the above characteristics of
living things. Your group will present your results to the class during the next class period. Your
results will include a brief description of the tests, the results of the tests (data), and a one
paragraph conclusion.
EVALUATE Answer the following questions.
1) List the characteristics of living things.
2) Which specimens were once living but are now dead?
3) Which specimens were never living?
4) What are some of the characteristics that non-living specimens share with living
specimens?
5) Living things outside of the Earth might have different characteristics than those of
Earth. How might living things be different in other worlds?
6) At which hierarchy level does life begin?
7) How can you differentiate life forms from complex chemical reactions?
8) Define the following words; nucleic acid, dormant.
Written Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
12
LAB #2, CELL THEORY
LESSON OVERVIEW
The cell theory introduces students to the cell and the concept of a theories as a unifying theme
or models of relationships. Since life begins at the cellular level, the characteristics of life can be
understood by examining the organization and functions of the component cells. The students
observe cells from the plant, animal, fungal, and protist kingdoms as an introduction to the five
kingdoms and the idea that all living things share common structures and organization.
STRANDS
Cells are the structural/functional units of life.
OBJECTIVES; After this lab the student will be able to
1) Define nucleus, cytoplasm, cell membrane, cell wall, chloroplast, vacuole, prokaryotic,
eukaryotic.
2) State the cell theory.
3) Compare the three main parts of common cells.
4) Compare differences between prokaryotic and eukaryotic cells.
5) Compare differences between plant and animal cells.
6) Calculate the magnification of a microscope’s field of view.
7) Create a wet mount of animal, plant, and fungi cells.
PASS SKILLS ADDRESSED
P1.2 Use appropriate tools (e.g., microscope, pipette, metric ruler, graduated cylinder,
thermometer, balances, stopwatches, etc.) when measuring cells, organisms,
populations, and ecosystems.
P2.1 Using observable properties, place cells, organisms, and/or events into a biological
classification system.
P2.2 Identify the properties by which a biological classification system is based.
P3.3 Use mathematics to show relationships within a given set of observations (e.g.,
population studies, biomass, probability, etc.).
P5.1 Interpret a biological model, which explains a given set of observations.
P6.3 Use a variety of technologies, such as hand tools, microscopes, measuring instruments, and
computers to collect, analyze, and display data.
1.1 Cells are composed of a variety of structures such as the nucleus, cell membrane, cell
wall, cytoplasm, ribosomes, mitochondria, and chloroplasts.
1.2 Cells can differentiate and may develop into complex multicellular organisms (i.e.,
cells, tissues, organs, organ systems, organisms).
3.1 Different species might look dissimilar, but the unity among organisms becomes
apparent from an analysis of internal structures, the similarity of their chemical
processes, and the evidence of common ancestry (e.g., homologous and analogous
structures).
13
MATERIALS AND PREPARATION
Methyl blue stain, toothpicks, elodea, protist suspension, cotton ball, wetting solution (1 drop
dish washing liquid per liter of water), moldy bread, iodine solution, a jar of bleach solution for
the cheek cell slides, microscope slides, cover slips. If available a prepared slide with bacteria
should be set at a station for observation. The microscope will have to have at least 1000X
magnification and some immersion oil for the bacteria to be seen.
LESSON SEQUENCE
1) Engage the students by reviewing the use of the microscope and showing videos or film
of what they are going to see. Ask students what they know about cells and write prior
knowledge on the board or overhead.
2) Review use of the microscope.
3) Demonstrate making a wet mount of the cheek cells.
4) Demonstrate making a wet mount of the bread mold.
5) The students observe and draw pictures of the specimens and the bacteria if available.
6) The teacher should review the cell theory; All living things are made of cells, all cells
come from pre-existing cells, cells are the structural/functional units of life.
7) Students are provided with an unknown for identification. Suggestions include the yeast
suspension, some algae, or onion skin.
8) Students use the last ten minutes of class to review and enter findings in their lab
notebooks.
14
LAB #2, CELL THEORY
OBJECTIVES After this lab the student will be able to:
1) Define nucleus, cytoplasm, cell membrane, cell wall, chloroplast, vacuole, prokaryotic,
eukaryotic.
2) State the cell theory.
3) Compare the three main parts of common cells.
4) Compare differences between prokaryotic and eukaryotic cells.
5) Compare differences between plant and animal cells.
6) Calculate the magnification of a microscope’s field of view.
7) Create a wet mount of animal, plant, and fungi cells.
EXPLORE
Animal cells, You are the animal.
1) Put one small drop of water on the microscope slide.
2) Gently scrape the inside of your cheek with a toothpick, and stir the pick in the drop of water.
3) Dip the tooth-pick in the methyl blue stain, and stir the drop again.
4) Cover-slip the water drop and observe under the microscope. Look under low power to find
the cells, then increase to high power to identify and draw structures.
5) Draw the results in your lab notebook, labeling the cell membrane, nucleus, and cytoplasm.
Plant cells
1) Put a single drop of water on a slide.
2) Pull off an Elodea leaf and place it on the drop.
3) Cover-slip the slide and observe under low and high power.
4) In the data section, label the cell wall, cytoplasm, and chloroplasts.
Protista cells
1) Pull apart some strands from a cotton ball and place on your slide
2) Make a wet mount using a drop of water from the protest suspension.
3) Draw your results in the data section, labeling the cell membrane, cytoplasm, flagella.
Fungi cells
1) Put a single drop of wetting agent on a slide.
2) Pull a couple of strands of black bread mold from the culture with a tooth-pick and mix it with
the wetting agent. Then using the toothpick, apply a drop of iodine and stir.
3) Cover-slip and observe the fungal cells under low and high power.
4) Draw the results in the data section, labeling the cell wall, cytoplasm, and nuclei.
15
DATA
Draw the cells and label the underlined structures from the procedure section.
Plant cell
Animal cell
Fungal cell
Protista cell
16
ANALYSIS
Calculate the magnification of the lenses of your microscope:
ocular
times
objective
=
total magnification
Low power
_____
X
_______
=
______________
Medium power
_____
X
_______
=
_______________
High power
_____
X
_______
=
_______________
EXPLAIN
All living things are made of cells, and the cells of all organisms share common features. The
Eukaryotic cells are large, and have a prominent nucleus. These are the cells of plants, animals,
protists and fungi. These cells are easily seen under a light microscope, and often the larger cell
structures such as chloroplasts can also be seen. The prokaryotic cells are much smaller, and are
almost undetectable under the most powerful light microscopes. Bacteria are prokaryotic and
they lack a nucleus, or any large organelles.
EXTEND
Using the specimen that your teacher provided, make a wet mount. Draw the cells in the space
below and identify them as plant, animal, fungi, or protist.
Identity____________________________
EVALUATE Answer the following questions.
1) Contrast the cheek cells with the Elodea cells. Which structures were common to both, which
were unique to the organism?
2) Why can’t the cell membrane be identified in the Elodea cells?
3) What are the purposes of the cell wall, and of the chloroplasts in the Elodea?
4) When Robert Hooke observed cork cells in 1665, what cellular structure was he observing?
5) What is the purpose of the cell membrane?
6) What is the purpose of the nucleus?
17
7) About how many bacterial cells would fit inside an animal cell?
8) Why do higher power objectives show a smaller field of view than the lower power
objectives?
Written Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
18
LAB #3, MITOSIS AND THE CELL CYCLE
LESSON OVERVIEW
Organisms grow and develop by adding new cells. The cell cycle lab introduces the concept of
chromosomes as genetic components, and introduces the concept of chromosome division, which
will become the basis of understanding meiosis and genetics. During the lab the students identify
cells in various stages of mitosis and determine the amount of time the cell spends in each stage.
After determining the times the students construct a cell cycle.
STRAND
All cells come from pre-existing cells.
Chromosomes contain genes.
OBJECTIVES After this lab the student should be able to;
1) Define cytokinesis, interphase, prophase, metaphase, anaphase, telophase, cell plate and
cleavage furrow.
2) Identify cells in each stage of mitosis.
3) Construct a cell cycle map using collected data.
4) Contrast mitotic stages in plant and animal cells.
5) Estimate the rate of mitosis in plant cells.
PASS SKILLS ADDRESSED
P1.1 Identify qualitative and quantitative changes in cells, organisms, populations, and
ecosystems given condition (e.g. temperature, mass, volume, time, position, length,
quantity, etc.) before, during, and after an event.
P2.1 Using observable properties, place cells, organisms, and/or events into a
biological classification system.
P2.2 Identify the properties by which a biological classification system is based.
P3.3 Use mathematics to show relationships within a given set of observations (e.g.,
population studies, biomass, probability, etc.).
P4.8 Identify and/or create an appropriate graph or chart from collected data, tables, or
written description (e.g., population studies, plant growth, heart rate, etc.).
1.1 Cells are composed of a variety of structures such as the nucleus, cell membrane, cell
wall, cytoplasm, ribosomes, mitochondria, and chloroplasts.
1.2 Cells can differentiate and may develop into complex multi-cellular organisms (i.e.,
cells, tissues, organs, organ systems, organisms).
3.1 Different species might look dissimilar, but the unity among organisms becomes
apparent from an analysis of internal structures, the similarity of their chemical
processes, and the evidence of common ancestry (e.g., homologous and analogous
structures).
19
MATERIALS
Microscopes with 400X lenses
White fish blastula slides
Onion root tip slides
LESSON
1) The instructor engages students by reviewing the cell theory and the aspect that all cells come
from pre-existing cells.
2) The students observe the whitefish blastula slides and identify the stages of mitosis, and the
characteristics of the nucleus during each mitotic stage.
3) The instructor asks for the defining characteristics of each stage, and reviews how to find the
dividing cells on an onion root tip.
4) The students expand by counting the onion root tip cells. By calculating the percent of cells in
each stage the student is able to find the amount of time each stage takes. Starting at
interphase the students make a pie graph that demonstrates the cell cycle.
5) The class evaluates what has been learned, and enters a summary in their journals or lab
books.
20
LAB #3, MITOSIS AND THE CELL CYCLE
OBJECTIVES, After this lab the student should be able to;
1) Define cytokinesis, interphase, prophase, metaphase, anaphase, telophase, cell plate and
cleavage furrow.
2) Identify cells in each stage of mitosis.
3) Construct a cell cycle map using collected data.
4) Contrast mitotic stages in plant and animal cells.
5) Estimate the rate of mitosis in plant cells.
EXPLORE
Identification of mitotic stages;
First locate the Whitefish blastula using low power (10X), then observe under high power
(40X). The events of each stage are described below. Make a drawing of each stage using the
space provided to the right of the description.
______________________________________________________________________________
1)During interphase the cell is growing and performing
protein synthesis. The DNA is unwound and
duplicated. This is the stage most cells are in most
of the time.
______________________________________________________________________________
2) During prophase the two centrioles move apart.
Some microtubular rays extend between
the two centrioles, forming a spindle. The
chromosomes begin to condense within the
nucleus and the nuclear envelope begins to
disintegrate.
______________________________________________________________________________
3) During metaphase the chromosomes migrate to
the center of the cell and form the or metaphase
plate.
21
4) During anaphase the two chromatids of
each chromosome are drawn apart toward
opposite centrioles. By late anaphase the
separated chromatids, now called
chromosomes, are at opposite ends of the
spindle. The two clusters of chromosomes
are identical in number and genetic composition.
____________________________________________________________________________
5) Telophase is characterized by a elongation of the
dividing mother cell. During this time a
nuclear envelope reforms around the
chromosomes, and the astral rays and
chromosomes become less distinct.
Cytokinesis occurs as the cleavage furrow
Between the two nuclei deepens. The spindle
fibers, which still extend between daughter cells, are disassembled as
the two daughter cells separate
____________________________________________________________________________
EXPLAIN
Mitosis is the process by which cells make more cells. Cells need to make copies of
them-selves for reproduction, cell replacement, growth, and to repair damaged structures. Cell
division has several stages in which the cell doubles in size and materials. Each daughter cell is
an exact duplicate of the original cell, and each cell has the same DNA and genes as the original.
Before the cells can divide, the DNA must be duplicated (replication), and packaged in a
chromosome. The chromosome prevents the strings of DNA from breaking apart during cell
division. The events of mitosis are the placement and orientation of the chromosomes in the
nucleus.
There are several differences between plant and animal mitosis. The most obvious
difference occurs when the cells themselves divide. Plant cells form a cell plate, between the two
cells, that later becomes the cell wall. Animal cells have spindle fibers that originate from the
centrioles. Each spindle fiber is attached to the centromeres of the animal chromosomes, and
pulls the chromosomes apart during anaphase.
EXTEND
Plant cell mitosis
We will estimate the length of time for each stage of cellular division. In general, plant
cells in the actively dividing regions of the plant (meristems), take about 24 hrs to divide. By
calculating the amount of time spent in each stage, we can estimate the amount of time required
for mitosis in plant cells.
22
PROCEDURE
1) Using the low power objective (10X), locate the meristematic regions of the onion root tip.
This area occurs about 1/4 the distance from the tip. Shift to the high power objective
(40X), and count the number of cells that are in each stage of mitosis, (prophase,
metaphase, anaphase, and telophase).
2) Repeat this count in at least two more non-overlapping fields of view and record the data in
Table #1.
3) Consider that it takes each cell 24 hours to complete the cell cycle. You can calculate the
amount of time spent in each phase from the percent of cells in that stage.
Percent of cells in stage X 1,440 minutes =_______________ minutes of cell cycle in stage.
Table #1, Number of Alium cells in phases of mitosis
Phase
Field 1
Field 2
Field 3
Total
% cells
counted
Time in
each stage
Interphase
Prophase
Metaphase
Anaphase
Telophase
total cells
counted
ANALYSIS
Use the time spent in each stage to generate a pie graph in the space below, labeling each stage in
order.
Percent time spent in each stage of mitosis.
Stage
Minutes
Hours
________________
__________
__________
________________
__________
__________
________________
__________
__________
________________
__________
__________
________________
__________
__________
23
EVALUATE, Answer the following questions:
1) What can you infer about the amount of time an onion root tip cell spends in each stage of
mitosis?
2) List four reasons that cells need to divide.
3) Name two differences between plant and animal cell division.
4) During which stage of mitosis does the DNA copy itself?
5) During which stage of mitosis does the cell plate occur?
6) Why is the blastula the best place to see animal cell division?
7) What is the purpose of the spindle fibers in animal cells?
8) How is eukaryotic cell division different from prokaryotic cell division?
9) What are chromosomes made of?
10) What is the function of chromosomes in cells?
Written Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
24
LAB #4, OSMOSIS AND DIFFUSION
LESSON OVERVIEW
This lesson addresses a fundamental aspect of cellular structure and function. The cell
membrane controls the movement of material into and out of the cell. The concept of heat and
molecular motion that students developed in eighth grade is expanded to include the motion of
molecules across a membrane due to differential concentrations of ions or solutes. The idea will
be readdressed when developing the concepts of the Photosynthetic/Respiratory mechanism of
using differential concentrations of ions across a membrane to generate ATP within the
mitochondria and chloroplast.
STRAND
Cells are the structural/functional units of life.
OBJECTIVES, After this lab the student should be able to:
1) Define diffusion, osmosis, semi-permeable membrane, solute, solution, hypotonic, hypertonic,
isotonic.
2) Collect data by measuring the effects of solute size and concentration gradients on diffusion
across selectively permeable membranes.
3) Measure and interpret the effects of water gain or loss in animal and plant cells.
4) Design and conduct an investigation to find the concentration of solute in plant cells.
PASS SKILLS ADDRESSED
P1.1 Identify qualitative and quantitative changes in cells, organisms, populations, and
ecosystems given condition (e.g. temperature, mass, volume, time, position, length,
quantity, etc.) before, during, and after an event.
P1.2 Use appropriate tools (e.g., microscope, pipette, metric ruler, graduated cylinder,
thermometer, balances, stopwatches, etc.) when measuring cells, organisms, populations,
and ecosystems.
P1.3 Use appropriate System International (SI) units (i.e., grams, meters, liters, degrees
Celsius, and seconds); and SI prefixes (i.e., micro-, milli-, centi-, and kilo-) when
measuring cells, organisms, populations, and ecosystems.
P3.3 Use mathematics to show relationships within a given set of observations (e.g.,
population studies, biomass, probability, etc.).
P4.3 Interpret data tables, line, bar, trend and/or circle graphs.
P4.5 Evaluate experimental data to draw the most logical conclusion.
P4.7 Communicate or defend scientific thinking that results in conclusions.
P4.8 Identify and/or create an appropriate graph or chart from collected data, tables, or
written description (e.g., population studies, plant growth, heart rate, etc.).
P5.1 Interpret a biological model which explains a given set of observations.
P6.3 Use a variety of technologies, such as hand tools, microscopes, measuring
instruments, and computers to collect, analyze, and display data.
P6.4 Inquiries should lead to the formation of explanations or models (physical,
conceptual, and mathematical). In answering questions, students should engage in
25
discussions (based on scientific knowledge, the use of logic, and evidence from
the investigation) and arguments that encourage the revision of their explanations,
leading to further inquiry.
1.1 Cells are composed of a variety of structures such as the nucleus, cell membrane, cell
wall, cytoplasm, ribosomes, mitochondria, and chloroplasts.
5.1 The complexity and organization of organisms accommodate the need for obtaining,
transforming, transporting, releasing, and eliminating matter and energy used to
sustain the organisms (i.e., photosynthesis and cellular respiration).
MATERIALS AND PREPARATION
Dialysis tubing, Scales, Sugar solutions of .2M, .4M, .6M, .8M,1.0M and an unknown, Cork hole
borer, Potato or Yam, Iodine solution, Starch solution, lots of cups. The big solo party cups work
well and last several years.
LESSON SEQUENCE
1) The instructor can easily engage the students with a demonstration of diffusion, and following
discussion of entropy. A bottle of perfume (or ammonia) at one end of the classroom
creates a concrete model of molecules moving from an area of higher concentration to
lower concentration.
2) The diffusion of dye in water can be performed using the largest beaker in the class or a one
gallon pickle jar. Red or blue dye work best.
3) During the exploratory phase it is easiest for the teacher to fill all the dialysis tubes for each
solution at the same time. For example, fill all six stations with 0.2M solution at the same
time. Have the students dry, weigh, mark the time, and immerse the bags before going to
0.4M. this will save a lot of time and keeps the students working.
4) When students are tying their dialysis tubing, it is very important that the sides are twisted and
folded over to prevent leaking.
5) Some students will have difficulty designing a good lab for the elaborate phase. The teacher
needs to remind them that water can move into, or out of the cell.
6) Students present their findings on overhead sheets after the activity. Each presentation should
include their hypothesis, a graph of the results, and a conclusion.
26
LAB #4, OSMOSIS AND DIFFUSION
OBJECTIVES After this lab the student will be able to:
1) Define diffusion, osmosis, semi-permeable membrane, solute, solution, hypotonic, hypertonic,
isotonic.
2) Collect data by measuring the effects of solute size and concentration gradients on diffusion
across selectively permeable membranes.
3) Measure and interpret the effects of water gain or loss in animal and plant cells.
4) Design and conduct an investigation to find the concentration of solute in plant cells.
EXPLORE
1) Diffusion.
Without moving the beaker around, place one drop of dye in the beaker and observe what
occurs. Continue with the lab procedure, and answer the questions in Evaluation.
2) Selective Permeability of Membranes.
1) Fill the cup marked “Iodine solution” 2/3rds full of water.
2) Add 5mls of iodine solution to the water.
3) Take a dialysis bag, fill it with starch solution, tie it off, and place it in the cup.
4) Observe at the end of the hour and record changes in Table #1.
3) Movement Due to Concentration.
1) Get six cups and label them 0.0M, 0.2M, 0.4M, 0.6M, 0.8M, and ?.
2) Fill each cup 2/3rds full of distilled water.
3) Tie off one end of the dialysis bags with thread, then fill each bag with the
appropriate sugar solution (0.0M, 0.2M, etc.).
4) Tie off the free end of the dialysis bag, dry the bag, then weigh the bag.
5) Record the mass of the bag on Table #2 under “Initial mass”.
6) Place the bag in the appropriate cup for 30 minutes.
7) At the end of 30 minutes, remove the bag, dry it, weigh it, and record the final
mass in Table #1.
DATA
1) Record the changes in the beaker of dye.
2) Record changes of the dialysis bag in the iodine solution. Iodine and starch turn dark blue or
black. What has changed, the solution inside or outside of the bag?
27
Table #1, Weight Change of Dialysis Bags.
Bag #
Concentration
1
0.0M
2
0.2M
3
0.4M
4
0.6M
5
0.8M
6
?
Initial mass (gms)
Final mass (gms)
% Change
ANALYSIS
1) Calculate the percent change of mass of each of the dialysis bags, and record the % change on
Table #1. The formula for calculating percent change is;
% change = (Final mass - initial mass / initial mass) X 100
2) Using a best fit line, graph the % change of mass due to concentration of bags 1-5. Percent
change will be the Y axis, and concentration will be the X axis.
3) Using your graph, extrapolate the concentration of sugar solution in the mystery bag.
28
EXPLAIN
All atoms are constantly in motion. Gas atoms move the fastest, the atoms in liquids are
slower, and the atoms in solids move the slowest. The movement of atoms is a form of kinetic
energy called heat and the measurement of this movement is called temperature. Diffusion is the
random movement of molecules from an area of higher concentration to an area of lower
concentration. In biology, we are mostly interested in the movement of water molecules and
solute molecules in an aqueous solution. Since water molecules move randomly, the solute will
eventually become evenly distributed in solution.
Osmosis is the random movement of molecules across a semi-permeable membrane.
The membrane is called semi-permeable because only small molecules (like iodine) can pass
through, and large molecules (like starch) bounce off. Osmosis is driven by the same forces that
drive diffusion; temperature, concentration and pressure. During osmosis, water diffuses from an
area of high water (low solute) concentration to an area of low water (high solute) concentration.
The movement of water is passive, requiring no energy from the cell.
EXTEND
Using a potato, scale, and solutions of 0.0M, 0.2M, 0.4M, 0.6M, and 0.8M solutions
design a lab exercise to find the concentration of solute in potato cells. In the lab each group will
generate a hypothesis, a protocol, a data chart, a graph, and a summary. Each group will present
findings after the lab to the class.
State your hypothesis here:
______________________________________________________________________________
EVALUATION Answer the following questions.
1) What occurred to the concentration of dye in the beaker?
2) What is the source of energy for diffusion?
3) How could you speed diffusion without touching the beaker
4) What is a semi-permeable membrane?
5) In our two tests, which molecules could pass through the dialysis bag? Which could
not?
6) What was the estimated concentration of the mystery bag?
7) What are the factors that affect osmosis?
8) Why can’t sharks live in Lake Hefner?
9) Define hypertonic, isotonic, and hypotonic.
10) What is the importance of osmosis to living cells?
Written Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
29
LAB #5, ENZYME ACTIVITY
LESSON OVERVIEW
This lesson builds on the concepts of diffusion and heat to explain enzyme kinematics.
Reaction rates are determined by the number of times an enzyme makes contact with the
substrate. The reaction rates are influenced by temperature, pH, concentration of enzyme, and
concentration of the substrate. The students initiate a reaction and measure the rate by
determining the amount of product produced over time.
OBJECTIVES, After this lesson the student will be able to:
1) Define enzyme, catalyst and active site.
2) Collect data measuring the relationship between enzyme structure and function.
3) Analyze and produce graphs representing the effects of variables on enzyme activity.
4) Design and conduct an investigation measuring the effects of temperature, pH, or enzyme
concentration to reaction rates.
PASS SKILLS ADDRESSED
P1.1 Identify qualitative and quantitative changes in cells, organisms, populations, and
ecosystems given condition (e.g. temperature, mass, volume, time, position, length,
quantity, etc.) before, during, and after an event.
P1.2 Use appropriate tools (e.g., microscope, pipette, metric ruler, graduated cylinder,
thermometer, balances, stopwatches, etc.) when measuring cells, organisms,
populations, and ecosystems.
P1.3 Use appropriate System International (SI) units (i.e., grams, meters, liters, degrees
Celsius, and seconds); and SI prefixes (i.e., micro-, milli-, centi-, and kilo-) when
measuring cells, organisms, populations, and ecosystems.
P3.3 Use mathematics to show relationships within a given set of observations (e.g.,
population studies, biomass, probability, etc.).
P4.1 Select appropriate predictions based on previously observed patterns of evidence.
P4.2 Report data in an appropriate manner.
P4.3 Interpret data tables, line, bar, trend and/or circle graphs.
P4.5 Evaluate experimental data to draw the most logical conclusion.
P4.8 Identify and/or create an appropriate graph or chart from collected data, tables, or
written description (e.g., population studies, plant growth, heart rate, etc.).
P6.3 Use a variety of technologies, such as hand tools, microscopes, measuring
instruments, and computers to collect, analyze, and display data.
P6.4 Inquiries should lead to the formation of explanations or models (physical,
conceptual, and mathematical). In answering questions, students should engage in
discussions (based on scientific knowledge, the use of logic, and evidence from
the investigation) and arguments that encourage the revision of their explanations,
leading to further inquiry.
2.1 Cells function according to information contained in the master code of DNA )i.e.,
cell cycle, DNA to DNA, DNA to RNA). Transfer RNA and protein synthesis
will be taught in life science courses with rigor greater than Biology I.
30
MATERIALS
CBL gas pressure gauge
Hydrogen peroxide
Potato or liver
Pans of water
HCl and NaOH
LESSON SEQUENCE
1) The explore phase uses potato or liver extract to induce a reaction with Hydrogen peroxide
that liberates oxygen as a by product. The oxygen can be detected using a burning splint
test. The important aspect of this reaction is that the oxygen is produced by the hydrogen
peroxide, not by the potato extract. It is very important to boil a piece of potato to
denature the enzymes. No reaction occurs with the boiled potato.
2) During the elaborate phase the students can choose temperature, pH, or enzyme concentration
to calculate the relationship between reaction rates and enzymes. The program for the gas
probe sensor,
Gas pressure program for enzyme lab
{1,0}=>L1
Send L1, 1
{1,1,1,0,0,1}=>L1
Send L1,1
{4,1,1,1,0,0.4587}=>L1
Send L1,1
{3,3,120,1,0,0,0,0,1}=>L1
Send L1,1
Wait
Get L2, 1
Get L1,1
3) The students will generate a hypothesis and display results to the class after the exercise.
Distribute overhead sheets and the groups need to present their hypothesis, a graph of
their results, and a conclusion.
31
LAB #5, ENZYME EXPLORATORY EXERCISE
OBJECTIVES, After the lab the student will be able to;
1) Define enzyme, catalyst and active site.
2) Collect data measuring the relationship between enzyme structure and function.
3) Analyze and produce graphs representing the effects of variables on enzyme activity.
4) Design and conduct an investigation measuring the effects of temperature, pH, or enzyme
concentration to reaction rates.
EXPLORE
1) Get a small cube of liver or potato and drop it in the 3% hydrogen peroxide solution. Describe
what you see.
2) Mash up 10 grams of potato or liver and add 20 mls of distilled water. Squirt 2 mls of this
solution under the gas collection jar that is filled with hydrogen peroxide. Describe the
reaction you see.
1) Perform a “glowing splint” test inside the gas
collection jar.
a) What gas is being produced by the reaction?
b) What is the source of the gas?
c) How could you test that?
2) Get another small cube of potato or liver and, using forceps, hold the cube in boiling
water for one minute. After the cube has cooled, drop it in the hydrogen peroxide
solution. Do you see the same reaction as in #1? Is the potato/liver or the hydrogen
peroxide reacting?
3) Generate a hypothesis to test the relationship between potato extract, hydrogen peroxide
and the produced gas.
Write a one paragraph summary of the exercise in your lab notebook, and outline the relationship
between catalysts and reactions.
32
LAB # 5, ENZYME ACTIVITY
EXPLAIN
Enzymes are proteins that act as catalysts. A catalyst works by lowering the energy of
activation of a reaction. In the induced fit model of enzymes, the substrate attaches to the active
site with hydrogen bonds, then both enzyme and substrate conform to each other like a clasp
handshake. The stress of the induced fit causes the reaction to occur. The active site of the
enzyme has a specific shape that is determined by the sequence of amino acids in the protein.
Factors influencing the rate of enzyme mediated reactions are temperature, pH and enzyme
concentration.
Temperature. At low temperatures there is very little free energy to induce a reaction so
the reaction rate is slow. At high temperatures proteins tend to denature as hydrogen bonds, ionic
bonds and hydrophobic attractions are broken and new bonds form. This denaturing of the
enzyme changes the conformation of the active site and the enzyme loses it’s catalytic ability.
pH and ion concentration. At low and high pH, the ionic and hydrogen bonds are
broken and reform. This change in conformation changes the shape of the active site and inhibits
the ability for the active site to bind to the substrate. The catalytic ability of the enzyme is
reduced or stopped.
Enzyme concentration. In a saturated solution, all of the enzyme active sites are filled
with substrate molecules. At this point the reaction rate is constant. When the concentration of
substrate starts to drop, the reaction rate slows.
In this lab we will measure the reaction of hydrogen peroxide with catalase. When
hydrogen peroxide decomposes, it releases gaseous oxygen. The oxygen gas increases the gas
pressure in the vessel.
2H2O2  2H2O + O2
We will measure the rate of reaction as a change in gas pressure. The higher the pressure, the
larger the number of molecules of oxygen being produced, and the faster the reaction.
PROCEDURE
Extracting enzyme.
1)Chop about 40g of raw potato into small pieces, and mash together with a little saline solution.
Mix the mashed potato with 50mls of distilled water in a 125ml flask. Let them sit for 15
minutes on ice, occasionally swirling until the water is very cloudy.
2) Strain the extract and keep on ice until needed. The ice prevents denaturing and oxidation of
enzymes. Assemble the apparatus as in Diagram #1.
3) Set up calculator according to teacher instructions to collect gas pressure data.
4) Push the “PRGM” button, then choose the enzyme program. The CBL will start to collect
data when the “ENTER” button is pushed.
33
Setting up the data collection apparatus
Diagram #1, Data collection apparatus
PROCEDURE
1) Fill the 1000ml beaker with 750ml of water of the correct temperature. Maintain the
temperature with either hot water, or ice.
2) Fill the test tube with 2 mls of catalyst mixture and submerge in the 1000ml beaker for four
minutes to allow the temperature to equilibrate.
3) Measure 4 mls of hydrogen peroxide.
4) Hit the enter button on the calculator to start data collection, wait 30 seconds, then mix the
hydrogen peroxide with the catalyst mixture.
5) Quickly seal the test tube with the cork, and start swirling the beaker.
6) Once the calculator is finished collecting data, hit ENTER to find the highest pressure.
7) Record the highest pressure in Table #1.
34
DATA
Table #1, Reaction Rates at Different Temperatures
Trial #
Temp (oC)
Initial pressure
(ATM)
Final pressure
(ATM)
Change
(ATM)
Time (min)
1
6
2
6
3
6
4
6
5
6
6
6
Reaction
rate
ANALYSIS
In the space below, graph the relationship between the temperature and the reaction rate.
Present your group results to class. Your write up will include your model, graphs of your results
and a summary.
35
EVALUATE Answer the following questions.
1) What is an enzyme?
2) What is a catalyst?
3) How do enzymes allow reactions to occur?
4) What determines the activity of an enzyme?
5) What are three factors that influence enzyme activity?
6) Graph the relationship between reaction rates and enzyme concentration.
7) Graph the relationship between pH and enzyme mediated reactions.
8) Graph the relationship between temperature and enzyme mediated reactions.
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
36
LAB #6, CALORIE MEASUREMENT
LESSON OVERVIEW
Calorie measurement acts as an introduction to the topics of energy and oxidation. Since
biologically available energy is stored in the molecular bonds of carbohydrates, we can liberate
this energy in an oxidation reaction.
STRAND
Energy is stored in molecular bonds
Cells are the structural/functional units of life
Matter is recycled while energy is lost as heat
OBJECTIVES, After this lab the student will be able to:
1) Define calorie, oxidation and molecular bond.
2) Relate the mnemonic OIL-RIG to the oxidation-reduction transfer of electrons.
3) Measure the number of calories in a gram of food using a calorimeter.
4) Calculate the efficiency of an experiment.
PASS SKILLS ADDRESSED
P1.2 Use appropriate tools (e.g., microscope, pipette, metric ruler, graduated cylinder,
thermometer, balances, stopwatches, etc.) when measuring cells, organisms, populations,
and ecosystems.
P1.3 Use appropriate System International (SI) units (i.e., grams, meters, liters, degrees
Celsius, and seconds); and SI prefixes (i.e., micro-, milli-, centi-, and kilo-) when
measuring cells, organisms, populations, and ecosystems.
P3.1 Evaluate the design of a biology laboratory investigation.
P3.3 Use mathematics to show relationships within a given set of observations (e.g.,
population studies, biomass, probability, etc.).
P4.2 Report data in an appropriate manner.
P4.8 Identify and/or create an appropriate graph or chart from collected data, tables, or
written description (e.g., population studies, plant growth, heart rate, etc.).
P6.3 Use a variety of technologies, such as hand tools, microscopes, measuring
instruments, and computers to collect, analyze, and display data.
4.1 Matter on the earth cycles among the living and nonliving components of the
biosphere.
5.1 The complexity and organization of organisms accommodate the need for obtaining,
transforming, transporting, releasing, and eliminating matter and energy used to
sustain the organisms (i.e., photosynthesis and cellular respiration).
5.2 As matter and energy flow through different levels of organization of living systems
and between living systems and the physical environment, chemical elements are
recombined in different ways by different structures. Matter and energy are
conserved in each change (i.e., water cycle, carbon cycle, nitrogen cycle, food
webs, and energy pyramids).
37
MATERIALS AND PREPARATION
The calorimeters can be made from small steel juice cans and a thermometer. Use a ring stand to
hold it all together. Pecans, cotton candy, marshmallows, and corn chips all work well.
LESSON SEQUENCE
1) Engage the students by burning cotton candy “What is the source of energy in cotton
candy?”
2) During the explore section the students learn to measure calories using a simple
calorimeter devised from a juice can. They can then compare their findings with the
USDA at http://www.nal.usda.gov/fnic/foodcomp/.
3) During the extend portion of the lesson students devise a lab comparing the caloric
content of three chosen foods. Students then compare their results to the food package or
the USDA web site.
4) Students enter findings or summaries in lab books or journals.
38
LAB #6, CALORIE MEASUREMENT
OBJECTIVES, After this lab the student will be able to:
1) Define calorie, oxidation and molecular bond.
2) Relate the mnemonic OIL-RIG to the oxidation-reduction transfer of electrons.
3) Measure the number of calories in a gram of food using a calorimeter.
4) Calculate the efficiency of an experiment.
EXPLORE
1) Carefully measure 100ml of DH2O into the calorimeter, and place it on the ring stand.
2) Weigh the food, record the mass in Table #1, and balance the food on the wire below the
calorimeter. Adjust the calorimeter until it is about 4-5 inches above the food. Maintain
the same height for each sample.
3) Take the initial temperature of the water and record it on Table #1.
4) Light the food, and while gently stirring the water, record the highest temperature achieved in
the can in Table #1.
5) Allow the can to cool and empty the water into the sink.
6) Calculate the number of calories released for each gram of food and record in Table #2
7) Using the chart on the food package, calculate the expected number of calories released per
gram of each food. Record this data in Table #3.
DATA
Table #1, Released calories of foods.
Food
Mass (gms)
Initial temp. oC (I)
Final temp. oC (F)
Calories
(F-I)/100 mls
Calories /gram
(F-I)/100 mls/grams
Table #2, Number of calories per gram.
Temp difference
(F-I)
Food
ANALYSIS
1) Calculate the percent error of our homemade calorimeters by using the following formula
and record your results in table #3.
Percent error = Expected value minus collected value divided by the expected value.
Table #3, Percent error
Food
Calories/gram
Expected calories
39
Difference
% Error
EXPLAIN
Energy is stored in molecular bonds. Covalent bonds hold molecules together because the
atoms of the molecule share common electrons. If there is enough free energy in the environment
(or an enzyme), oxygen can strip an electron from the molecule, consuming energy. The electron
attaches to a new molecule releasing energy. If the energy released is more than the energy
consumed, the reaction is exothermic and releases heat into the environment.
Oxidation is the loss of an electron. The oxygen is reduced because it gains an electron
(negative charge). Oxidation is loss (OIL), reduction is gain (RIG). The free energy released
from the reaction (as heat) is measured in units of calories. A calorie is the amount of heat
required to raise one gram of water one degree Celsius. A kilocalorie (kCal) is the amount of
energy required to raise one kilogram of water one degree Celsius. What we call
We can measure the relative number of kilocalories in food by building a crude
calorimeter, and burning the food underneath while measuring the change in temperature of a
known volume of water. Professional calorimeters are much more efficient, but this exercise will
give us a practical idea of the concept.
EXPAND
1) Design an investigation to determine the caloric content of three common foods and compare
your results with those of the USDA at the web site
http://www.nal.usda.gov/fnic/foodcomp/.
2) Write a specific “if, and, therefore” hypothesis.
3) Design a controlled experiment based upon your hypothesis.
a) Design and write your procedure.
b) Design table and graphs for collecting and interpreting data.
4) Your lab will be scored by the following criteria. Theory 10 pts, hypothesis 10 pts, procedure
15 pts, data collection 15 pts, data analysis 10 pts, conclusion 10 pts. We will perform the
lab next class period, so bring your lab write up with the theory, hypothesis, procedure,
and tables for data collection.
Generate a hypothesis here; ____________________________________________________
______________________________________________________________________________
EVALUATION, Answer the following questions.
1) What determines the number of calories in a food?
2) Which foods had the highest number of calories?
3) Draw a glucose molecule.
4) Draw a fat molecule.
5) What was the original source of energy to build the molecules of the tested foods?
6) Describe how you would test the caloric content of a Big Mac.
Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
40
LAB #7, CELLULAR RESPIRATION
LESSON OVERVIEW
The purpose of the cellular respiration lab is to explain the relationship between the
sugars in a seed and the energy required for growth and reproduction.
STRAND
Energy is stored in molecular bonds
Cells are the structural/functional units of life
Matter is recycled while energy is lost as heat
OBJECTIVES; DURING THIS LESSON THE STUDENT SHOULD LEARN
1) Describe the general process of metabolism in living organisms.
2) Write the equation for cellular respiration.
3) Draw a mitochondria and label the major structures.
4) Collect data measuring the respiration rate of a living organism.
5) Design and conduct an experiment measuring the relationship between respiration rates and
temperature.
PASS SKILLS ADDRESSED
P1.1 Identify qualitative and quantitative changes in cells, organisms, populations, and
ecosystems given condition (e.g. temperature, mass, volume, time, position, length,
quantity, etc.) before, during, and after an event.
P1.2 Use appropriate tools (e.g., microscope, pipette, metric ruler, graduated cylinder,
thermometer, balances, stopwatches, etc.) when measuring cells, organisms,
populations, and ecosystems.
P1.3 Use appropriate System International (SI) units (i.e., grams, meters, liters, degrees
Celsius, and seconds); and SI prefixes (i.e., micro-, milli-, centi-, and kilo-) when
measuring cells, organisms, populations, and ecosystems.
P3.1 Evaluate the design of a biology laboratory investigation.
P3.2 Identify the independent variables, dependent variables, and controls in an
experiment.
P3.3 Use mathematics to show relationships within a given set of observations (e.g.,
population studies, biomass, probability, etc.).
P3.4 Identify a hypothesis for a given problem in biology investigations.
P4.1 Select appropriate predictions based on previously observed patterns of evidence.
P4.2 Report data in an appropriate manner.
P4.3 Interpret data tables, line, bar, trend and/or circle graphs.
P4.4 Accept or reject hypotheses when given results of a biological investigation.
P4.5 Evaluate experimental data to draw the most logical conclusion.
P4.6 Prepare a written report describing the sequence, results, and interpretation of a
biological investigation or event.
P4.7 Communicate or defend scientific thinking that results in conclusions.
P4.8 Identify and/or create an appropriate graph or chart from collected data, tables, or
41
written description (e.g., population studies, plant growth, heart rate, etc.).
P6.1 Formulate a testable hypothesis and design an appropriate experiment relating to the
living world.
P6.2 Design and conduct biological investigations in which variables are identified and
controlled.
P6.3 Use a variety of technologies, such as hand tools, microscopes, measuring
instruments, and computers to collect, analyze, and display data.
P6.4 Inquiries should lead to the formation of explanations or models (physical,
conceptual, and mathematical). In answering questions, students should engage in
discussions (based on scientific knowledge, the use of logic, and evidence from
the investigation) and arguments that encourage the revision of their explanations,
leading to further inquiry.
1.1 Cells are composed of a variety of structures such as the nucleus, cell membrane, cell
wall, cytoplasm, ribosomes, mitochondria, and chloroplasts.
4.1 Matter on the earth cycles among the living and nonliving components of the
biosphere.
5.1 The complexity and organization of organisms accommodate the need for obtaining,
transforming, transporting, releasing, and eliminating matter and energy used to
sustain the organisms (i.e., photosynthesis and cellular respiration).
5.2 As matter and energy flow through different levels of organization of living systems
and between living systems and the physical environment, chemical elements are
recombined in different ways by different structures. Matter and energy are
conserved in each change (i.e., water cycle, carbon cycle, nitrogen cycle, food
webs, and energy pyramids).
MATERIALS AND PREPARATION
Each lab group will require two respirometers consisting of a large test tube some cotton soaked
in KOH, a #4 stopper and a pipette that measures in 1/10ths of a millimeter. The water baths are
used to keep the temperature consistent throughout the lab exercise. Pinto beans need to be
germinated about 5 days prior to the lab.
LESSON SEQUENCE
1) Students can be engaged by reviewing the relationship between calorie measurement and
oxygen consumption.
2) Students explore by measuring respiration of germinating beans.
3) The students elaborate by designing an experiment to determine the effects of temperature on
respiration. Students can use a variety of organisms such as grasshoppers, rolly-pollies,
crickets, germinating beans, peas, earthworms, etc. The KOH is caustic and will kill
beans or earthworms on contact.
4) The lab groups present findings at the end of the exercise on an overhead sheet. The
information should include a hypothesis, data graph, and conclusion.
5) The lab is followed by a formal lab write up using the format at the beginning of the book.
42
LAB #7, CELLULAR RESPIRATION
OBJECTIVES, After this lab the student will be able to;
1) Describe the general process of metabolism in living organisms.
2) Write the equation for cellular respiration.
3) Draw a mitochondria and label the major structures.
4) Collect data measuring the respiration rate of a living organism.
5) Design and conduct an experiment measuring the relationship between respiration rates and
temperature.
EXPLORE
Student #1.
1) Get two glass test tubes and mark them 1 and 2.
2) Push a small wad of absorbent cotton in the bottom of each tube. Saturate the cotton with 1 ml
of potassium hydroxide (KOH) to absorb the carbon dioxide.
3) Lightly pack a small wad of non-absorbent cotton loosely on top of the first wad.
4) Get two corks with graduated pipettes.
Student #2
1) Quickly count twenty five germinating beans and measure the approximate volume in a 50ml
graduated cylinder. Record the volume and place the beans in Test tube #1.
2) Pour glass beads into the cylinder until the volume of the germinating and non-germinating
beans is the same as the volume of the germinating beans.
Group
1) Immerse the respirometers in the water bath with the pipettes in the air for 5 minutes, this
allows the temperatures of the respirometers to equilibrate.
2) At the end of 5 minutes, submerge the respirometers in the water baths. After 1 minute record
the time as time zero in your data chart, and take your first volume reading.
3) Every five minutes, record the volume of air in the test tubes in Table #1.
4) To measure the volume of oxygen consumed, calculate the difference at each reading by
subtracting the volume at time X from the initial reading at time 0.
Difference = (initial volume at time 0) - ( volume at time X)
5) To account for changes due to temperature and air pressure, calculate the corrected difference
by subtracting the differences between the control volume (beads only)and the bean air
volume. Corrected difference = Difference - Difference of beads alone
6) Place your corrected difference on the board, then calculate class averages for the beads alone
and the germinating beans.. Place these results in Table #2.
43
Figure #1, Respirometers in water bath.
DATA
Table #1, Respirometer Gas Volumes
Beads Alone
Time (min)
Initial
Reading at
Time X
Germinating Beans
Diff.*
Reading at
Time X
XXXX
Diff.*
Corrected Diff.^
XXXX
XXXX
0-5
0-10
0-15
0-20
0-25
0-30
*Difference = (initial reading at time 0) - (reading at time X)
^Corrected difference = (initial reading at time 0 - reading at time X) – ( initial bead reading at time o - bead reading at time X)
44
ANALYSIS
Table #2, Class Averages of Corrected Volume Differences of Bean Oxygen Consumption.
Time (min)
Beads alone (ml)
Germinating beans (ml)
5
10
15
20
25
30
Using best fit lines for each set of results, graph the results of the class averages for germinating
and non-germinating beans, using time as the X axis, and volume as the Y axis.
45
EXPLAIN
All living things use energy. The harvesting of molecular bond energy by an organism is
called cellular respiration. During aerobic respiration the mitochondria transfers the molecular
bond energy within a glucose molecule to the molecular bond energy of ATP. The balanced
equation of aerobic respiration is as follows:
C6H12O6 + 6O2 + 30 ADP + 30 PO4 -------------------> 6H2O + 6CO2 + 30 ATP
The source of glucose in the bean seed is the starch stored in the cotyledons (seed halves) made
by the parent plant during photosynthesis. All seeds contain a tiny plant embryo that is dormant
until germination. When the seed absorbs water, the embryo germinates and uses the starch in
the cotyledons as an energy source for growth until the plant is mature enough to conduct
photosynthesis.
To measure respiration, we can either measure a change in the amounts of reactants or the
amounts of products. We measured a change in the volume of the reactant oxygen. We provided
a chemical that absorbs carbon dioxide, so the only change of gas volume should be the volume
of oxygen that is consumed. As the oxygen is consumed, the volume of the gas in the
respirometer decreases. Gasses change volume very easily due to changes in temperature and
atmospheric pressure. To insure that the only variable that we measured is oxygen consumption,
we will have a control respirometer that has the same volume of material, but only contains inert
glass beads that do not consume oxygen or produce carbon dioxide.
EXTEND
1) Design an experiment to measure the efficiency of respiration at either different temperatures,
germinating vs. non-germinating beans, long term germination (1-2 days), or another
organism like crickets, earthworms, or sow bugs.
2) Write a specific “if, and, therefore” hypothesis.
3) Design a controlled experiment based upon your hypothesis.
a) Design and write your procedure.
b) Design table and graphs for collecting and interpreting data.
4) Your lab will be scored by the following criteria. Theory 10 pts, hypothesis 10 pts, procedure
15 pts, data collection 15 pts, data analysis 10 pts, conclusion 10 pts. We will perform the
lab next class period, so bring your lab write up with the theory, hypothesis, procedure,
and tables for data collection.
Generate a hypothesis here; ____________________________________________________
______________________________________________________________________________
EVALUATE, Answer the following questions..
1) Describe the relationship between the amount of oxygen consumed and time for both the
germinating and the non-germinating beans.
2) Besides oxygen consumption, what are two other causes for respirometer volume
change?
46
3) What was the control in the experiment? What variables did the control eliminate?
4) What was the result of germination vs. non-germination on bean seed respiration?
5) Estimate how much faster the germinating beans were respiring than the non-germinating
beans.
6) Many seeds contain a lot of oil. Why are lipids a good source of energy for a seed?
7) How did the starch get into the seed?
8) Peal and pry your seed open. Draw and label the parts of a seed below.
Parts of a seed
9) Draw a picture of a mitochondria in the space below. Label the inner membrane, the
outer membrane and the matrix.
Mitochondria structure
Written Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
47
LAB #8, PHOTOSYNTHESIS
LESSON OVERVIEW
The purpose of the photosynthesis lab is to demonstrate the conversion of light energy to
chemical bond energy. This activity measures the production of oxygen gas volume as an
indicator of photosynthetic efficiency.
STRAND
Energy is stored in molecular bonds
Cells are the structural/functional units of life
Matter is recycled while energy is lost as heat
OBJECTIVES, After this lab the student will be able to:
1) Describe the process of photosynthesis.
2) Write the equation for photosynthesis.
3) Draw a chloroplast and label the major structures.
4) Collect data measuring photosynthetic rate.
5) Design and conduct an investigation measuring photosynthetic rates at different temperatures,
different light intensities, or different wavelengths of light.
PASS SKILLS ADDRESSED
P1.1 Identify qualitative and quantitative changes in cells, organisms, populations, and
ecosystems given condition (e.g. temperature, mass, volume, time, position, length
quantity, etc.) before, during, and after an event.
P1.2 Use appropriate tools (e.g., microscope, pipette, metric ruler, graduated cylinder,
thermometer, balances, stopwatches, etc.) when measuring cells, organisms,
populations, and ecosystems.
P1.3 Use appropriate System International (SI) units (i.e., grams, meters, liters, degrees
Celsius, and seconds); and SI prefixes (i.e., micro-, milli-, centi-, and kilo-) when
measuring cells, organisms, populations, and ecosystems.
P3.1 Evaluate the design of a biology laboratory investigation.
P3.2 Identify the independent variables, dependent variables, and controls in an
experiment.
P3.3 Use mathematics to show relationships within a given set of observations (e.g.,
population studies, biomass, probability, etc.).
P3.4 Identify a hypothesis for a given problem in biology investigations.
P4.1 Select appropriate predictions based on previously observed patterns of evidence.
P4.2 Report data in an appropriate manner.
P4.3 Interpret data tables, line, bar, trend and/or circle graphs.
P4.4 Accept or reject hypotheses when given results of a biological investigation.
P4.5 Evaluate experimental data to draw the most logical conclusion.
P4.6 Prepare a written report describing the sequence, results, and interpretation of a
biological investigation or event.
P4.7 Communicate or defend scientific thinking that results in conclusions.
48
P4.8 Identify and/or create an appropriate graph or chart from collected data, tables, or
written description (e.g., population studies, plant growth, heart rate, etc.).
P6.1 Formulate a testable hypothesis and design an appropriate experiment relating to the
living world.
P6.2 Design and conduct biological investigations in which variables are identified and
controlled.
P6.3 Use a variety of technologies, such as hand tools, microscopes, measuring
instruments, and computers to collect, analyze, and display data.
P6.4 Inquiries should lead to the formation of explanations or models (physical,
conceptual, and mathematical). In answering questions, students should engage in
discussions (based on scientific knowledge, the use of logic, and evidence from
the investigation) and arguments that encourage the revision of their explanations,
leading to further inquiry.
1.1 Cells are composed of a variety of structures such as the nucleus, cell membrane, cell
wall, cytoplasm, ribosomes, mitochondria, and chloroplasts.
4.1 Matter on the earth cycles among the living and nonliving components of the
biosphere.
5.1 The complexity and organization of organisms accommodate the need for obtaining,
transforming, transporting, releasing, and eliminating matter and energy used to
sustain the organisms (i.e., photosynthesis and cellular respiration).
5.2 As matter and energy flow through different levels of organization of living systems
and between living systems and the physical environment, chemical elements are
recombined in different ways by different structures. Matter and energy are
conserved in each change (i.e., water cycle, carbon cycle, nitrogen cycle, food
webs, and energy pyramids).
MATERIALS AND PREPARATION
Each lab group needs two healthy sprigs (4-5 inches) of elodea, one 500ml Erlenmeyer
flask, a #4 stopper with a hole, bent glass tubing, stop watch or clock with second hand, small
ruler in mm units, fish or water bowl to act as heat sink, and a strong light source.
The sodium bicarbonate solution provides a carbon source for the elodea. Dissolve half a
small box of baking soda in a gallon of water. Tinted cellophane is available at the local craft
store.
LESSON SEQUENCE
1) Engage the students by having them observe Elodea sprigs under the microscope and
identifying the chloroplasts.
2) The students explore by using the apparatus to collect photosynthetic rate data.
3) The students expand by designing a lab to collect data measuring the variables, light intensity,
light wavelength, or temperature.
4) The students evaluate their results by presenting to the class their hypothesis, their data
graphs, and a summation of the activity.
49
LAB #8, PHOTOSYNTHESIS
OBJECTIVES, After this lab the student will be able to:
1) Describe he process of photosynthesis.
2) Write the equation for photosynthesis.
3) Draw a chloroplast and label the major structures.
4) Collect data measuring photosynthetic rate.
5) Design and conduct an investigation measuring the relationship between light
wavelength, light intensity and photosynthetic rate.
EXPLORE
1) Place several healthy sprigs of elodea in the test tube, cut side up.
2) Add the 3% sodium bicarbonate solution to the top of the test tube, and push the stopper with
the bent glass tubing on until the water is about ½ to ¾ the way down the tube.
3) Mark the meniscus with a marker.
4) Set the tube in front of the light, with the fish bowl to act as a heat sink.
5) Mark the change in the meniscus every 5 minutes for 15 minutes and record the change in
millimeters.
6) Convert the millimeter reading to milliliter by multiplying the distance by r2.
APPARATUS
DATA
Table #1, Photosynthetic rate of elodea
Time
0
5
Distance
(mm)
Volume (ml)
10
50
15
20
EXPLAIN
Photosynthesis is the process in which plants convert light energy into chemical bond
energy. During photosynthesis light hits a chlorophyll molecule to provide the energy to split
water, H2O. The hydrogen (H+) is used as an energy source to build glucose molecules, and the
oxygen (O2) is released into the atmosphere as a waste product of the reaction.
6H2O + 6CO2  C6H12O6 + 6O2
ASSIGNMENT
1) Design an experiment to measure the efficiency of photosynthesis at different temperatures,
light intensities or wavelengths using the materials provided.
2) Write a specific “if, and, therefore” hypothesis.
3) Design a controlled experiment based upon your hypothesis.
a) Design and write your procedure.
b) Design table and graphs for collecting and interpreting data.
4) Your lab will be scored by the following criteria. Theory 10 pts, hypothesis 10 pts, procedure
15 pts, data collection 15 pts, data analysis 10 pts, conclusion 10 pts. We will perform the
lab next class period, so bring your lab write up with the theory, hypothesis, procedure,
and tables for data collection.
Generate a hypothesis here; ____________________________________________________
______________________________________________________________________________
EVALUATION
1) Look up the structure of a chloroplast. Draw a chloroplast and label the following structures:
outer membrane, inner membrane, stroma, granum.
2) What is the role of carbon dioxide in photosynthesis?
3) What was the mathematic relationship between light intensity and photosynthesis?
4) What was the effect of different wavelengths to photosynthesis?
5) What is a pigment?
6) What colors or the light spectra do plants absorb?
Written Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
51
LAB #9, KARYOTYPING AND CHROMOSOME THEORY
LESSON OVERVIEW
This lab is an introduction to chromosomes and the principle that chromosomes occur in
pairs. This lesson serves as a baseline concept and is later used during genetics to explain why
genes occur in pairs, and why each allele of a pair can be different. This concept is also
important in explaining the relationship between DNA, genes, chromosomes and genetic
expression.
STRAND
Chromosomes occur in pairs.
OBJECTIVES; DURING THIS LESSON THE STUDENT SHOULD LEARN
1) Define karyotype, haploid, diploid, homologous pair, and non-disjunction.
2) State the chromosome theory.
3) Organize chromosomes according to size, centromere location and banding
pattern.
4) Identify common human anamolies caused by non-disjunction.
PASS SKILLS ADDRESSED
P4.8 Identify and/or create an appropriate graph or chart from collected data, tables, or
written description (e.g., population studies, plant growth, heart rate, etc.).
P5.1 Interpret a biological model which explains a given set of observations.
1.1 Cells are composed of a variety of structures such as the nucleus, cell membrane, cell
wall, cytoplasm, ribosomes, mitochondria, and chloroplasts.
2.1 Cells function according to information contained in the master code of DNA )i.e.,
cell cycle, DNA to DNA, DNA to RNA). Transfer RNA and protein synthesis
will be taught in life science courses with rigor greater than Biology I.
2.2 A sorting and recombination of genes in reproduction results in a great variety of
possible gene combinations from the offspring of any two parents (i.e., Punnett
squares and pedigrees). Students will understand the following concepts in a
single trait cross: alleles, dominant trait, recessive trait, phenotype, genotype,
homozygous, and heterozygous.
MATERIALS AND PREPARATION
Karyotypes are easily available from Carolina or the internet. The karyotype should be large
enough that the students can identify banding, size and centromere location with some accuracy.
This project works much better with paper than with computers.
52
LAB #9, KARYOTYPING AND CHROMOSOME THEORY
OBJECTIVES, After this lab the student will be able to:
1) Define karyotype, haploid, diploid, homologous pair, and non-disjunction.
2) State the chromosome theory.
3) Organize chromosomes according to size, centromere location and banding
pattern.
4) Identify common human anamolies caused by non-disjunction.
EXPLORE
1) Using the handout from the instructor cut out the individual chromosomes from Karyotype A
and match them according to size, centromere location, and banding pattern.
2) Tape the matched chromosomes to Chart #1, “Human Karyotyping Form A”.
DATA
Chart #1, Human Karyotype A.
1
2
3
6
7
8
13
14
15
19
20
9
21
53
4
5
10
11
12
16
17
18
22
23
ANALYSIS
1) Determine the sex of the individuals in A. Record your results in Table #1.
2) Count the number of autosomes (non sex chromosomes) in Human Karyotype A and record
your results in Table #1.
Table #1, Karyotype Analysis
Karyotype
Sex
# Autosomes
Mutation
A
EXPLAIN
Chromosomes are located within the nucleus of the cell and are composed of DNA and
proteins. The chromosomes are a way of packaging DNA and appear prior to mitosis and meiosis
to prevent damage and mutations. Since chromosomes are composed of DNA, and genes are
determined by the sequence of nucleotides in DNA, chromosomes contain genes. Each human
somatic cell (body cell) contains 23 pairs of chromosomes for a total of 46. Of each pair of
homologous chromosomes, one comes from each parent. The homologous chromosomes match
in size, match in location of the centromere, and match in banding patterns. The chromosome
theory states;
1) Genes are located on chromosomes.
2) In diploid organisms, chromosomes occur in pairs (homologs).
3) The number of chromosomes is constant within a species.
Each gene on a chromosome has a matching gene on the same location of its matching
homologous chromosome, so there are two genes (alleles) for each trait. The 23rd pair of
chromosomes are the sex chromosomes which are of unequal size and determine the sex of the
offspring. Females have two X sex chromosomes while males have the larger X and a smaller Y
sex chromosome.
Meiosis is the process producing sperm and ova cells that contain one of each pair of
chromosomes. Some genetic disorders occur during meiosis by the addition or subtraction of
chromosomes due to imperfect pairing. A karyotype is a photograph of the chromosomes taken
during Prophase of meiosis. The chromosomes can then be cut out of the picture and arranged by
size, centromere location, and banding patterns. Missing or broken chromosomes indicate
abnormalities. In the following lab we will observe some karyotypes, cut out matching
chromosomes, and determine the effects of the resulting chromosome patterns.
54
EXPAND
Follow the same procedure you used for Karyotype A on Karyotype B, and tape the
matching chromosomes to Chart #2, “Human Karyotype B”.
Chart #2, Human Karyotype B
1
2
3
6
7
8
13
14
15
19
20
9
21
4
5
10
11
12
16
17
18
22
23
ANALYSIS
1) Determine the sex of the individuals in B. Record your results in Table #2.
2) Count the number of autosomes (non sex chromosomes) in Human Karyotype B and record
your results in Table #1.
Table #2, Karyotype Analysis
Karyotype
Sex
# Autosomes
A
55
Mutation
EVALUATION, Answer the following questions.
1) Look up the cause of the following syndromes and record the type of mutation, the number of
chromosomes in a diploid cell, and the karyotype characteristics on Table #2.
Table #2, Common Chromosomal Syndromes.
Syndrome
Type of mutation
# of chromosomes
I.D. on karyotype
Trisomy 21
(Down’s syndrome)
5p deletion
Klinefelter’s
syndrome
Turner’s syndrome
Fragile X syndrome
2) How are the X and the Y chromosomes different?
3) What characteristics of the chromosomes are most helpful in matching homologous pairs?
4) In which Karyotype was there evidence of a syndrome? Which syndrome?
5) How are chromosomes like shoes?
6) What are chromosomes made of?
7) What is the role of chromosomes within the cell?
8) During which phase of the cell cycle do chromosomes appear?
9) During which phase f meiosis do the homologous chromosomes segregate?
10) Gametes are sex cells that are haploid. How are gametes different from somatic body cells?
Written Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
56
LAB #10, DNA ISOLATION FROM PLANT CELLS
LESSON OVERVIEW
The purpose of the DNA extraction is to provide a concrete example of DNA. The
strands are clumped but can be lightly stained with methyl blue or another basic stain. The DNA
can be stored in alcohol and frozen for later electrophoresis or other analysis.
STRAND
Genes are located on chromosomes
Chromosomes are made of DNA
OBJECTIVES; After this lesson the student will be able to:
1) Describe the effect of detergents on cell membranes.
2) Describe the structure and list the nucleotides of DNA.
3) Conduct an investigation to isolate DNA from plant cells.
PASS SKILLS ADDRESSED
1.1 Cells are composed of a variety of structures such as the nucleus, cell membrane, cell
wall, cytoplasm, ribosomes, mitochondria, and chloroplasts.
2.1 Cells function according to information contained in the master code of DNA (i.e.,
cell cycle, DNA to DNA, DNA to RNA). Transfer RNA and protein synthesis
will be taught in life science courses with rigor greater than Biology I.
P1.2 Use appropriate tools (e.g., microscope, pipette, metric ruler, graduated cylinder,
thermometer, balances, stopwatches, etc.) when measuring cells, organisms,
populations, and ecosystems.
MATERIALS AND PREPARATION
Soap/salt solution (100ml woolite, 15g NaCl, 900ml deionized water), 60OC incubator,
ice, ethanol, cheesecloth, onions or bananas, stirring rods.
57
LAB #10, DNA ISOLATION FROM PLANT CELLS
OBJECTIVES After this lab the student will be able to;
1) Describe the effect of detergents on cell membranes.
2) Describe the structure and list the nucleotides of DNA.
3) Conduct an investigation to isolate DNA from plant cells.
EXPLORE
1) Coarsely chop an onion and blend it with 100ml of detergent solution.
2) Pour the mixture into a beaker and incubate at 60OC for 15 minutes.
3) Mix 3 mls of spit water with the 8% NaCl solution.
4) Cool the mixture in an ice bath for 5 minutes, then filter through 4 layers of cheese cloth.
5) Place 6mls of onion filtrate in a test tube.
6) Immediately and carefully pour 9mls of ICE cold ethyl alcohol down the inside of the slanted
test tube. Slant the tube to reduce the mixing of the two liquids.
7) Let the ethanol sit for 2-3 minutes. Bubbles will form as the DNA precipitates out of solution.
8) Place a clean glass stirring rod in the test tube, and collect the DNA by winding it around the
rod, turning the rod in only one direction.
9) Place the 1 ml of alcohol and DNA in a small test tube, label it with your name and store in
the freezer for later.
EXPLAIN
Deoxyribonucleic acid is the molecule in cells that controls the sequence of amino acids
in proteins. Since proteins have both structural, and chemical roles in cells, the DNA molecule is
able to direct both the construction of materials and cellular reactions. DNA is located within the
nucleus and can be isolated by fracturing the cell, and separating the DNA from other cell
fragments.
The cells are first placed in a Sodium chloride solution, which acts as a buffer. The cells are then
placed in a detergent solution that fractures the outer and inner cell membranes. The ethyl
alcohol dehydrates and isolates the DNA so that it precipitates, and forms long mucoid strands.
In this lab the student will isolate DNA from onion cells.
EVALUATE
1) What is the role of DNA in the cell?
2) Draw the ladder diagram of the DNA molecule, labeling guanine, adenine, cytosine, and
thymine.
Written Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
58
LAB #11, PROBABILITY
LESSON OVERVIEW
Understanding probability is the basis for understanding the principles of genetics and
statistics. This lesson explores two fundamental relationships. The first concept addressed is how
an increased number of trials increase the accuracy of data samples. This idea is important when
designing experiments, understanding genetic drift, and the difference between antidotal
evidence and data. The second concept explored is the product rule. The product rule states that
the chance of two separate events occurring together is equal to the product of the chances of
them occurring apart. This concept explains how children of brown eyed parents can have blue
eyes. Punnett squares are based upon the product rule.
The probability of two separate events occurring at the same time is the product of the
chances of the two events. For example, the chance of rolling a 1 with a single dice is 1/6. The
chance of rolling “snake eyes”(a one on two separate dice at the same time) is 1/6 X 1/6 or 1/36.
In this lab we will toss a coin to measure the probability of heads and tails, then toss two coins to
measure the probability of two events occurring together.
STRAND
Chromosomes occur in pairs.
There is an equal chance of either allele occurring
OBJECTIVES; DURING THIS LESSON THE STUDENT SHOULD LEARN
1) Define probability, chance, ratio, rate, and occurrence.
2) Formulate the product rule from collected data.
3) Measure probability and make a prediction based upon probability.
4) Derive the relationship between an increased number of trials and the accuracy
of data.
PASS SKILLS ADDRESSED
P3.3 Use mathematics to show relationships within a given set of observations (e.g.,
population studies, biomass, probability, etc.).
P4.1 Select appropriate predictions based on previously observed patterns of evidence.
P6.4 Inquiries should lead to the formation of explanations or models (physical,
conceptual, and mathematical). In answering questions, students should engage in
discussions (based on scientific knowledge, the use of logic, and evidence from
the investigation) and arguments that encourage the revision of their explanations,
leading to further inquiry.
2.2 A sorting and recombination of genes in reproduction results in a great variety of
possible gene combinations from the offspring of any two parents (i.e., Punnett
squares and pedigrees). Students will understand the following concepts in a
single trait cross: alleles, dominant trait, recessive trait, phenotype, genotype,
homozygous, and heterozygous.
59
MATERIALS AND PREPARATION
Each group of two students needs two coins and a cup. A pair of dice for each group
would also come in handy.
LESSON SEQUENCE
1) Engage students by having them flip coins, roll dice, or picking a random number from a
box or hat. Have them provide definitions for chance, probability or ratio to provide on
the board. Refer to their definitions at the end of the lesson.
2) Students explore by collecting data when they flip coins. The students begin by flipping a
single coin then explore the relationship of flipping two coins. Allow the students to
derive the product rule themselves.
3) Explain. Formalize the product rule as the chance of two separate events occurring
together is equal to the product of the chances of them occurring apart.
4) A possible extension would be for students to derive the addition rule by throwing dice.
60
LAB #11, PROBABILITY
OBJECTIVES; After this lab the student will be able to;
1) Define probability, chance, ratio, rate, and occurrence.
2) Formulate the product rule from collected data.
3) Measure probability and make a prediction based upon probability.
4) Derive the relationship between an increased number of trials and the accuracy
of data.
EXPLORE
Part One, Tossing a single coin.
1) Using a single coin, toss it and record the result in Table #1.
2) Repeat the toss 9 times and record the results as “Trial #1" in Table #1.
3) Switch partners and repeat the ten tosses for Trial #2.
4) Continue tossing until a total of 100 tosses has occurred in 10 trials.
5) Total the data and record the results in Table #1.
DATA
Table #1, Results of Tossing a Single Coin.
Trial #
Number Heads
Number Tails
1
2
3
4
5
6
7
8
9
10
Totals
61
EXPLAIN
Probability, rate, chance, ratio, percentage, and frequency are all the same thing, how often an
event occurs divided by the possible number of events. The simplest way to express probability
is with fractions. As a fraction, the numerator is the number of times something happens and the
denominator is the number of possible times the event could occur. When the fraction is solved,
the fraction becomes a percentage. Saying, “The rate of occurrence is 1/2" is the same as saying,
“The rate of occurrence is 50% (0.50)”.
EXPAND, Tossing two coins together.
1) Put two coins of different value in the cup. The coin of lower value is “Coin #1", the coin of
higher value is “Coin #2".
2)Toss the coins together. If both coins come up heads, make a mark in 1H2H, if the lower coin is
heads and the higher coin is tails, record the data in 1H2T, if the lower coin is tails and the
higher coin is heads, mark the data table in 1T2H, and if both coins are tails, mark the data
table in 1T2T.
3) Repeat the process 9 times to complete Trial #1. Enter the results in Table #2.
4) Switch partners, and have the other partner complete Trial #2.
5) Continue until the trials are completed, and total the results.
Table #2, Results of Tossing Two Coins.
Trial #
1H2H
1H2T
1T2H
1T2T
1
2
3
4
5
6
7
8
9
10
Totals
ANALYSIS
1) Calculate the percentage of heads and tails in Table #1 by dividing the number of heads by the
number of tosses, and the number of tails by the number of tosses. Record in Table #3.
62
2) Calculate the percentage of 1H2H, 1H2T, 1T2H, and 1T2T by dividing the total number of each
column by the total number of tosses. Record your results on Table #3.
3) Using a bar graph display the percentage of heads, tails, 1H2H, 1H2T, 1T2H, and 1T2T from
Table #3.
Table #3, Percent Occurrence of Heads and Tails.
Result
Heads
Tails
1H2H
1H2T
1T2H
1T2T
%
Graph of occurrence frequency
EVALUATION, Answer the following questions:
1) For a single coin, what is the expected probability of tossing heads?
2) How often did the expected probability in question #1 occur in a single trial?
3) How close are the results of 100 tosses to the expected value?
4) How does increasing the number of tosses effect the amount of difference from the expected
value?
5) Is the answer to question #5 the same for two tails?
6) What is the expected relationship for two chance events occurring together?
7) When tossing two coins, what is the chance that either coin will be heads and the other tails?
8) Is the percentage for two heads (1H2H) closest to the sum, difference, or product of the two
percentages for the expected number of heads from each coin?
Written conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
63
LAB #12, GENETICS OF MASA
LESSON OVERVIEW
The genetics exercise compares a predicted ratio to an actual counted ratio. The students
start with a monohybrid cross and generate a prediction using the null hypothesis and chi-square
technique. After the skill is mastered students proceed with a dihybrid cross.
STRAND
Alleles occur in pairs
Dominant alleles mask recessive alleles
There is an equal chance of either allele occurring in a gamete
OBJECTIVES; DURING THIS LESSON THE STUDENT SHOULD LEARN
1) Predict genotypic and phenotypic ratios from known parents.
2) Generate a null hypothesis.
3) Collect data from counting phenotypes.
4) Predict parental phenotypes using chi-square analysis.
PASS SKILLS ADDRESSED
P1.1 Identify qualitative and quantitative changes in cells, organisms, populations, and
ecosystems given condition (e.g. temperature, mass, volume, time, position, length,
quantity, etc.) before, during, and after an event.
P3.3 Use mathematics to show relationships within a given set of observations (e.g.,
population studies, biomass, probability, etc.).
P3.4 Identify a hypothesis for a given problem in biology investigations.
P4.1 Select appropriate predictions based on previously observed patterns of evidence.
P4.2 Report data in an appropriate manner.
P4.5 Evaluate experimental data to draw the most logical conclusion.
P5.1 Interpret a biological model which explains a given set of observations.
2.1 Cells function according to information contained in the master code of DNA )i.e.,
cell cycle, DNA to DNA, DNA to RNA). Transfer RNA and protein synthesis
will be taught in life science courses with rigor greater than Biology I.
2.2 A sorting and recombination of genes in reproduction results in a great variety of
possible gene combinations from the offspring of any two parents (i.e., Punnett
squares and pedigrees). Students will understand the following concepts in a
single trait cross: alleles, dominant trait, recessive trait, phenotype, genotype,
homozygous, and heterozygous.
MATERIALS AND PREPARATION
The students have to have some skills using punnet squares. The hardest part is the null
hypothesis, in which the students predict “There will be no significant difference between the
data results and the predicted results.”
Get the corn ears from Carolina. Use the ones with Purple X Yellow, and Starchy X
Sweet.
64
LESSON SEQUENCE
1) Engage the students by showing them the ears of corn and having them predict the
genotypes and phenotypes of the parents. This is a good time to review Mendel’s
correlates about the law of dominance, the law of independent assortment and the law of
segregation.
2) Students explore by generating a “Null hypothesis” of the probability of the corn
phenotype, then performing a Chi-square analysis of the data.
3) The students expand by using the Chi-square analysis technique to measure the
probability of heterozygous parents in a dihybrid cross.
4) During the explanation phase be sure to refer to the rules of probability and the necessity
of large data groups to see and analyze trends.
5) Students evaluate the exercise by writing a summation.
65
LAB #12, GENETICS OF MASA
OBJECTIVES After this lab the student will be able to:
1) Predict genotypic and phenotypic ratios from known parents.
2) Generate a null hypothesis.
3) Collect data from counting phenotypes.
4) Predict parental phenotypes using chi-square analysis.
EXPLORE, Monohybrid cross
1) The color purple is dominant over yellow in corn. Complete the punnett square to
calculate the predicted percentages of purple to yellow phenotypes by crossing two
heterozygous parents.
Table #1. Monohybrid cross Punnett square
Pp X Pp
% purple______________
% yellow______________
2) Generate a null hypothesis for the crossing of two heterozygous parents, and record in
data.
3) State the possible genotypes for yellow and purple kernels in Table #2.
4) Count the purple and yellow kernels on your cob then enter the data in Table #2.
5) Using your total number of kernels, predict the expected number of purple and yellow
kernels by multiplying the total number of kernels times your expected percentages.
Record in Table #2.
6) Find the difference between the expected number and the observed number. Enter in
Table #2.
DATA
Null hypothesis; _________________________________________________________
_______________________________________________________________________
66
Table #2 Results of F1 generation cross
PHENOTYPE
GENOTYPE
# Observed (o)
# Expected (e)
(o-e)
Purple
Yellow
Total
Analysis
Copy the data from Table #1 to Table #2 and calculate the Chi-square
Table #2, Chi square analysis of monohybrid cross data.
Phenotype Observed (o) Expected (e)
(o-e)
(o-e)2
(o-e)2
e
Purple
Yellow
Total
Sum
Critical values chart
Degrees of Freedom
1o
2o
3o
4o
5o
0.05
3.84
5.99
7.82
9.49
11.1
0.01
6.64
9.21
11.3
13.2
15.1
0.001
10.8
13.8
16.3
18.5
20.5
Probability
2) From the critical values chart, what is the number we have to be less than?__________
3) If your X2 number exceeds the number on the chart, then the null hypothesis is
rejected. Is your null hypothesis supported or rejected by the data?_____________
67
EXPLAIN
One of the roles of statistics is to know if generated data has significant differences from
predicted values, or if the differences are due to predictable error. A good test to see if data falls
within predicted results is the Chi-square test. We will first practice using the Chi square, then
we will analyze data from both monohybrid and dihybrid crosses.
PROCEDURE, dihybrid cross
EXDTEND
1) For the dihybrid cross, the F1 generation is heterozygous for kernel color and starchy-sweet,
with purple dominant and yellow recessive, and starchy dominant over sweet. Generate a
null hypothesis for the crossing of two heterozygous parents, and record in data.
2) State the possible genotypes for purple starchy, purple sweet, yellow starchy, and yellow
sweet on Table #5. Perform a dihybrid cross to predict the ratios of the phenotypes to the
genotypes in Table #5. Record expected percentage in Table #5.
3) Count the purple starchy, purple sweet, yellow starchy and yellow sweet kernels on your cob,
enter the data in Table #6.
Data
Null hypothesis for dihybrid cross___________________________________________
______________________________________________________________________
Table #5, Dihybrid cross of F1 Purple starchy and Purple starchy
PpSs X PpSs
# purple starchy_____Ratio__________percent_____
# purple sweet______Ratio__________percent_____
#yellow starchy_____Ratio__________percent_____
#yellow sweet______Ratio__________percent_____
68
ANALYSIS
Table #6, X2 Analysis of Dihybrid Cross
Phenotype
# Observed
# Expected (e)
(o)
purple, starchy
(o-e)
(o-e)2
(o-e)2
e
purple, sweet
yellow, starchy
yellow, sweet
total
total
sum=
1) How many degrees of freedom are there for a dihybrid cross?______________
2) Referring to the critical values chart, what is the probability value for these data?_____
3) Using the critical values chart, state whether your null hypothesis is validated or
rejected.
EVALUATE Answer the following questions:
1) What is the chance of two separate events occurring together?
2) If four events each have a ½ chance of occurring, what is the chance that they will all
occur together?
3) How are chromosomes like shoes?
4) What is a null hypothesis?
5) Where are genes located?
6) People have 23 pairs of chromosomes. How many different combinations of
chromosomes are there in an ova?
7) Define; heterozygous, homozygous, dominant, recessive, segregation.
Written conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
69
LAB #13, HUMAN GENETIC TRAITS
LESSON OVERVIEW
During this lab the students combine the skills developed calculating probability and use
the product rule to calculate frequency of an allele within a human population. The ideas that are
addressed are that dominant alleles do not necessarily dominate the genome, but the frequency
remains in stasis because of the product rule. This idea will be approached again during the study
of population evolution.
STRAND
Dominant alleles mask the expression of recessive allele.
Variations occur in populations.
OBJECTIVES; DURING THIS LESSON THE STUDENT SHOULD LEARN
1) Define allele, gene, dominant, recessive, phenotype, genotype, and allele
frequency.
2) Identify ten common human phenotypes.
3) Calculate the possible genotypes of individuals by phenotype.
4) Calculate the percent occurrence of alleles in a population.
PASS SKILLS ADDRESSED
P2.1 Using observable properties, place cells, organisms, and/or events into a
biological classification system.
P3.3 Use mathematics to show relationships within a given set of observations (e.g.,
population studies, biomass, probability, etc.).
P5.1 Interpret a biological model which explains a given set of observations.
2.1 Cells function according to information contained in the master code of DNA )i.e.,
cell cycle, DNA to DNA, DNA to RNA). Transfer RNA and protein synthesis
will be taught in life science courses with rigor greater than Biology I.
2.2 A sorting and recombination of genes in reproduction results in a great variety of
possible gene combinations from the offspring of any two parents (i.e., Punnett
squares and pedigrees). Students will understand the following concepts in a
single trait cross: alleles, dominant trait, recessive trait, phenotype, genotype,
homozygous, and heterozygous.
3.2 Species acquire many of their unique characteristics through biological adaptation,
which involves the selection of naturally occurring variations in populations.
Biological adaptations include changes in structures, behaviors, or physiology,
which may enhance or limit survival and reproductive success in a particular
environment.
MATERIALS AND PREPARATION
The PTC paper is readily available and inexpensive. This lab serves to quantify allele
frequency in a population. It is easier to introduce the concept of allele frequency now, and attain
mastery during the evolution section.
70
LESSON SEQUENCE
1) Engage the students by using the PTC paper to find the number of “Tasters” in the
classroom population. Since “Taster” is a dominant trait, and there are two alleles for
each trait, ask the students to estimate the allele frequency in the population, then use the
Hardy-Weinberg formula to see the accuracy of the estimate.
2) The students explore by collecting data and analyzing the frequency of common human
phenotypes.
3) The students extend by analyzing the collected data, and calculating allele frequency.
4) The students evaluate by writing a conclusion at the end.
71
LAB #13, HUMAN GENETIC TRAITS AND GENE FREQUENCY
OBJECTIVES After this lab the student will be able to;
1) Define allele, gene, dominant, recessive, phenotype, genotype, and allele
frequency.
2) Identify ten common human phenotypes.
3) Calculate the possible genotypes of individuals by phenotype.
4) Calculate the percent occurrence of alleles in a population.
EXPLORE
1) For each trait determine your phenotype and enter on Table #1.
2) Determine your possible genotypes for the trait, and enter on Table #1. A person with the
dominant phenotype can have either the homozygous or heterozygous genotype.
3) From the class data, calculate the percentage of homozygous recessives for each trait.
Possible genotypes and phenotypes. Each of the traits is determined by a dominant allele.
1) Tongue rolling (R). If you can roll your tongue into a circle, you are a tongue roller.
2) Free earlobe (F). If your earlobe dangles below the attached point, you have Free
earlobe.
3) Widows peak (W). If your forelock comes to a point.
4) Straight thumb (N). If you have a straight thumb, the top of the thumb forms a straight
line with the bottom segment when the thumb is extended.
5) Freckles (M). If you have any freckles, you have freckles.
6) Left over right hand crossing (L). You have this trait if your left thumb crosses over
your right when your hands are naturally crossed.
7) Chin cleft (C). You have a cleft chin if the center of the chin has an indentation
resembling a dimple.
8) Mid-digital hair (H). You have this trait if any hair is present on the middle section of
any of your fingers.
9) Taster (T). A taster can taste PTC paper.
10) Polydactylly (P). You have this trait if you have, or have ever had, six fingers or toes on
either hand or foot.
72
DATA
Table #1, Class results of Genetic Survey.
Traits
Yes
No
Possible genotypes
Class ratio (Y/N)
Dom/class total
% Homozygous
recessive
Tongue rolling (R)
Free earlobe (F)
Widow’s peak (W)
Straight thumb (N)
Freckles (F)
Thumb crossing (L)
Chin cleft (C)
Mid-digital hair (H)
Taster (T)
Polydactylly (P)
EXPLAIN
An organism’s phenotype is determined by both the genotype and the environment. The
genes located on the chromosomes of each cell determine the genotype of the organism. Since
diploid organisms receive one set of chromosomes from each parent, there are two genes for
each trait. The two genes for one particular trait are called alleles. A dominant allele masks the
expression of a recessive allele. A dominant allele is expressed if the organism is homozygous
dominant, or is heterozygous. The recessive allele is expressed if the organism is homozygous
recessive.
How often an allele occurs in a population is the allele frequency. Since each individual
in a population has a pair of alleles for each trait, the number of alleles is twice the population
number, and the frequency of occurrence is a proportion of the total number of alleles. Without
the influence of environmental factors, the allele frequency within a population will remain the
same from generation to generation. The equation for allele frequency is;
p + q = 100% (1.0)
p = the frequency of dominant alleles, and q = the frequency of recessive alleles.
73
We can calculate the frequency of an allele by knowing how often the recessive
phenotype occurs within the population. Since the chance of two events occurring together (two
different alleles in the same organism) is equal to the product of the chances of them occurring
separately, the equation for genotypic frequency of members of a population is:
(p + q) X (p + q) or p2 + 2pq + q2 = 100% (1.0)
where; p2 = the frequency of homozygous dominants, 2pq = the frequency of heterozygotes and
q2 = the frequency of homozygous recessives.
In the following lab we will first identify some common human traits and calculate the number
of individuals in our class population with these traits. Then we will calculate the allele
frequency for our class.
EXTEND
1) From the percentage of homozygous recessives (q2), calculate the frequency of recessive
alleles by taking the square root of q2. Enter this in Table #2 under “q”.
2) From the frequency of recessive alleles, calculate the frequency of dominant alleles and enter
this in Table #2. Since p + q = 1.0, p = 1.0 - q.
Table #2. Allele frequency for selected human traits.
Trait
q2
(% homozygous
recessive)
Tongue rolling (R)
Free Earlobe (F)
Widow’s peak (W)
Straight thumb (N)
Freckles (M)
Thumb crossing (L)
Chin cleft (C)
Mid digital hair (H)
Taster (T)
Polydactylly (P)
74
Frequency of q
Frequency of p,
(1.0 - q)
EVALUATE, Answer the following questions.
1) What is an allele?
2) Where are genes located in cells?
3) Did anybody in the class have the same combination of traits as you? Why?
4) Which dominant alleles have a higher frequency than the recessive alleles?
5) How could a recessive allele have a higher frequency in a population than a dominant allele?
6) Why does allele frequency have to begin with the recessive phenotype?
7) In a population of 1,200 people, 48 have yeller eye. Yeller eye is caused by a recessive allele.
What percentage of the population is heterozygous and therefore a carrier of “yeller
eye”?
Written Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
75
LAB #14, VARIATION WITHIN A POPULATION
LESSON OVERVIEW
The students measure beans and generate a bell curve from the data. There are many
different ways to perform this exercise. We could use student height, weight, tooth length, index
finger length, etc. The advantage of the pinto beans is the speed, practice using a millimeter
scale, and the ability to place the beans in a pile or cups to provide a concrete example of a bell
curve. If the beans are separated into six groups, this serves as a good introduction to the concept
of average or normal. Beans outside of average or normal are deviations. It is easy to review the
concept of number of trials verses accuracy, standard deviation, and norms.
STRAND
Variation occurs in populations
Populations are the units of evolution
OBJECTIVES, After this lab the student will be able to:
1) Collect size data from among members of a population.
2) Calculate the range of variation.
3) Develop a histogram that displays the size distribution of a population.
PASS SKILLS ADDRESSED
P3.3 Use mathematics to show relationships within a given set of observations (e.g.,
population studies, biomass, probability, etc.).
P4.2 Report data in an appropriate manner.
P4.8 Identify and/or create an appropriate graph or chart from collected data, tables, or
written description (e.g., population studies, plant growth, heart rate, etc.).
P5.1 Interpret a biological model which explains a given set of observations.
P5.3 Compare a model to the living world.
P6.4 Inquiries should lead to the formation of explanations or models (physical,
conceptual, and mathematical). In answering questions, students should engage in
discussions (based on scientific knowledge, the use of logic, and evidence from
the investigation) and arguments that encourage the revision of their explanations,
leading to further inquiry.
MATERIALS AND PREPARATION
Get 2 pounds of lima beans and count out 100 beans per baggy. Each student pair will
need 6 cups, 100 beans and some cooperation skills. It seems to go fastest when one student
measures and the other student places the bean in the appropriate cup. Beans that are not in the
initial range are “outliers” and should not be counted at all. This works so well that the beans in
the average group (within one standard deviation of the norm) usually add up to around 64, just
like the math model.
76
LESSON SEQUENCE
1) Engage the students by having them agree on a common definition for norm, or normal.
Students can also be lined up by height, and split into groups. “What is the average size?
How many students are of average height?”
2) The students explore by taking a sample of ten beans to find the size ranges. This
establishes the idea of variation in other populations.
3) The students extend by counting the number beans in each size group, and building a
histogram of the results.
4) The students then evaluate by answering questions and writing a conclusion.
77
LAB #14, VARIATION WITHIN A POPULATION
OBJECTIVES After this lab the student will be able to;
1) Collect size data from among members of a population.
2) Calculate the range of variation.
3) Develop a histogram that displays the size distribution of a population.
EXPLORE
1) From your bowl of lima beans, randomly count out ten, and measure each one for length
Millimeter
to the nearest millimeter. Put the lengths in order from smallest to largest. Record your
scale
findings in Table #1.
2) Subtract the size of the smallest bean from the largest bean. This is the size range of the
beans, or just the range. Record the range in Table #1.
3) Divide the range by six. This provides the size range of each group. Record the size
range of each group in Table #1.
4) Calculate the size range of each group by adding the size range from Step #3 to the
smallest size in Table #1. This is the size range of Group #1. Record in Table #2.
5) Calculate the size range of Group #2 by adding the size range to the largest size in Group
#1. Continue to calculate the range of each of the remaining five groups of beans and
record in Table #2.
6) Mark seven cups from 1-6 to hold the beans in each size range.
7) Measure 100 beans for size. Whichever size range the bean falls within, place the bean in
the appropriate cup.
8) Upon completion, count the number of beans in each cup. Record this in Table #3.
DATA
Table #1, Range of Lima Bean Sizes.
Size Range
Length of Lima beans (mm)
Size Range/6
(Largest-Smallest)
Table #2, Range of lengths in each group.
Group #
1
2
3
4
5
6
3
4
5
6
Size range
(mm)
Table #3, Number of beans in each group.
Group #
1
2
Number
78
ANALYSIS
Generate a histogram to show the number of beans within each size ranges.
1) On the X axis below, mark the size range and group number of each group from smallest
to largest.
2) Using the largest number in Table #3 as a guide, determine the scale of the Y axis.
EXPLAIN
All members of a population display variation within a character or trait. Often the
variations are very small, but even members of a species that at first seem very similar often
show a high degree of differentiation when more closely examined. Most natural populations
will display a bell curve distribution of types, with the largest number of individuals falling in an
average group.
A histogram is a type of graph used to indicate the number of individuals in a group. In
this exercise, the student will measure the variation among common lima beans and generate a
histogram to display the data.
EVALUATION
1) Which group contained the largest number of individuals?
2) What is the shape of the histogram?
3) What is the advantage of variation to a population?
4)Define average, norm, variation.
Written Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
79
LAB #15, POPULATION GENETICS
LESSON OVERVIEW
Population genetics provides an overview of the population as the unit of evolution. The
model also shows the effects of natural selection on allele frequency, how alleles are seldom
completely removed from the gene pool, and that dominant alleles do not overwhelm the gene
pool because of the product rule.
STRAND
Populations are the units of evolution
Alleles occur in pairs
Dominant alleles mask recessive alleles
Independent assortment
Survivors in a population pass genes to their offspring
OBJECTIVES; DURING THIS LESSON THE STUDENT SHOULD LEARN
1) Model changes of allele frequency and genotypes in the gene pool of a population
using the Hardy-Weinberg formula.
2) Describe the causes of allele frequency change.
3) Predict the effects of natural selection upon allele frequency.
4) Conclude that evolution is a change of allele frequency within a population.
5) Define genetic drift, natural selection, allele frequency and gene pool.
PASS SKILLS ADDRESSED
P1.1 Identify qualitative and quantitative changes in cells, organisms, populations, and
ecosystems given condition (e.g. temperature, mass, volume, time, position, length,
quantity, etc.) before, during, and after an event.
P3.3 Use mathematics to show relationships within a given set of observations (e.g.,
population studies, biomass, probability, etc.).
P4.1 Select appropriate predictions based on previously observed patterns of evidence.
P5.1 Interpret a biological model which explains a given set of observations.
P6.4 Inquiries should lead to the formation of explanations or models (physical,
conceptual, and mathematical). In answering questions, students should engage in
discussions (based on scientific knowledge, the use of logic, and evidence from the
investigation) and arguments that encourage the revision of their explanations, leading to
further inquiry.
2.1 Cells function according to information contained in the master code of DNA )i.e.,
cell cycle, DNA to DNA, DNA to RNA). Transfer RNA and protein synthesis
will be taught in life science courses with rigor greater than Biology I.
2.2 A sorting and recombination of genes in reproduction results in a great variety of
possible gene combinations from the offspring of any two parents (i.e., Punnett
squares and pedigrees). Students will understand the following concepts in a
single trait cross: alleles, dominant trait, recessive trait, phenotype, genotype,
homozygous, and heterozygous.
80
3.2 Species acquire many of their unique characteristics through biological adaptation,
which involves the selection of naturally occurring variations in populations.
Biological adaptations include changes in structures, behaviors, or physiology, which
may enhance or limit survival and reproductive success in a particular environment.
4.2 Organisms both cooperate and compete in ecosystems (i.e., parasitism and
symbiosis).
MATERIALS AND PREPARATION
Two packages of 50 index cards and mark them with a green marker.
LESSON SEQUENCE
1) Engage students by providing an example of a dominant allele, such as polydactyl or
widow’s peak, and calculate the allele frequency in the population. How do allele
frequencies change?
2) Explore. Students create a model of random reproduction and calculate allele frequency
change through five generations.
3) Expand. Students devise a lethal allele combination of homozygous dominant,
heterozygous, or homozygous recessives, and measure the change in allele frequency
over five generations.
4) Evaluate. Students evaluate the activity by answering questions and writing a summary.
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LAB #15, POPULATION GENETICS
OBJECTIVES After this lab the student will be able to
1) Model changes of allele frequency and genotypes in the gene pool of a population
using the Hardy-Weinberg formula.
2) Describe the causes of allele frequency change.
3) Predict the effects of natural selection upon allele frequency.
4) Conclude that evolution is a change of allele frequency within a population.
5) Define genetic drift, natural selection, allele frequency and gene pool.
EXPLORE
A) Calculating allelic frequency.
1) Take a small strip of PTC paper and press it to your tongue. A taster will sense a
slightly bitter taste. Tasters are the dominant phenotype. Record your possible
genotype(s) in Table #1.
2) From the number of non-tasters within the class, calculate the % of q2. Record
this on Table #1.
3) Calculate the frequency of p and q for both the North American and the class
population. Record your results on Table #1.
B) Allelic frequency in randomly reproducing populations.
1) Take 8 index cards, four that are marked “A” and four marked “a”. These cards
represent the alleles of gametes, “A” being dominant, and “a” being recessive.
2) Everyone is to begin as a heterozygote, “Aa”. Use two “A” cards and two “a” cards as
shown on Chart #1.
3) With a randomly selected partner replace yourself by randomly choosing one of your
four cards and placing it face upon the table while your partner does the same.
This is your new genotype. Record your new genotype in Table #2 under
“Generation #1", then repeat the process to replace your partner. Record the new
genotypes of the class on the board and on Table #2.
4) With your new genotype use the combination of cards shown in Chart #1, and repeat
step #3. Continue until 5 generations have passed.
Chart #1, Card Combinations of Genotypes
Genotypes
Card Combinations
Homozygous dominant (AA)
A,A,A,A
Heterozygous (Aa)
A,A,a,a
Homozygous recessive (aa)
a,a,a,a
C) Allelic frequency during selection. In this model we will select against the homozygous
recessive. The procedure is similar to that in Part #B.
1) Every student starts as a heterozygote with the cards A,A,a,a.
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2) Randomly choose another student as a partner to replace yourselves. Each student
again randomly chooses a card. If the genotype of the offspring is “aa” the
offspring dies and the students must repeat the process until the replacement is
“AA” or Aa”.Record the results on Table #3.
DATA
Table #1. Allelic Frequency of Tasters and Non-tasters
Tasters
North
American
Population
0.55
Class
population
#
%
% q2
(# nontasters/ # class)
Non-tasters
0.45
q
(square root of q2)
p
(1.0 - q)
0.45
#
%
Table #2, Changes in Allele Frequency Due to Random Mating.
OFFSPRING’S GENOTYPE
Generation
CLASS TOTALS FOR EACH GENOTYPE
(AA, Aa, aa)
AA
Aa
aa
0
1
2
3
4
5
Table #3, Changes in Allele Frequency Due to Natural Selection.
OFFSPRING’S GENOTYPE
Generation
CLASS TOTALS FOR EACH GENOTYPE
(AA, Aa)
AA
0
1
2
3
4
5
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Aa
ANALYSIS
1) Calculate the initial and final dominant and recessive allele frequencies for random
mating from generation #1 and generation #5 in Table #2. Record the results on Table #4.
Table #4. Allelic Frequency After Five Generations of Random Mating
GENERATION #AA, #Aa
#aa
%q2
%q
(#aa/#class)
( q 2)
1
%p
(1.0-%q)
5
2) To calculate the number of recessive alleles after selection against the homozygous
recessive, divide the number of heterozygotes by 2. Record your results on Chart #5.
Chart #5, Allelic Frequency After 5 Generations of Selection Against the Recessive
Generation #
# Homozygous
Dominants (AA)
# Heterozygotes
(Aa)
q = #heterozygotes /
2
1
5
EXPLAIN
A population contains individuals within a species that are isolated from other members
of the same species. The most common kind of isolation is geographic, but populations can also
be isolated by time, behavior, developmental stages, or mechanical differences. The allelic
frequency within a population will remain constant with that of the rest of the species under the
following conditions;
1) The breeding population is large. This eliminates the effect of chance.
2) Mating is random. Individuals show no preference for a particular phenotype.
3) There is no net mutation of alleles.
4) No differential migration occurs. No net emigration or immigration.
5) There is no natural selection. All phenotypes have an equal chance of producing
viable offspring.
When members of a splinter population are no longer able to interbreed and produce viable
offspring with members of the parent population, a new species has been formed.
To measure the frequency of an allele within a population we use the following formula
to represent the dominant and recessive alleles for a particular trait.
p + q = 1.0
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Where p represents the dominant allele and q represents the recessive allele. Since
members of a population have two alleles for each trait, and the chance (frequency) of
two events occuring together is the product of the chance (frequency) of them occurring
apart. In a randomly reproducing population the genotypic frequency equals (p+q)(p+q).
The result is;
p2 + 2pq + q2 = 1.0
In the above equation p2 represents the homozygous dominant frequency, 2pq represents
the heterozygote frequency and q2 represents the homozygous recessive frequency. Since
the homozygous dominants and heterozygotes within a population have the same
phenotype, we can only identify the homozygous recessive frequency from the observing
the phenotype.
To calculate the frequency of alleles within a population we first count the
number of homozygous recessives (q2) and divide that by the total number of the
population to find the homozygous recessive frequency. Once q2 is known q is found by
taking the square root of q2. If q is known p is easily found since 1.0 - q = p. Once both p
an q are known, the frequency of homozygous dominants (p2), and heterozygotes (2pq)
are easily calculated.
In the following lab exercise the student will calculate the allele frequency of a
population, measure a population under reproductive equilibrium, and study the effects of
natural selection upon allelic frequency.
EVALUATE Answer the following questions..
1) From Table #1, would the frequency of Tasters in the class be closer or more different
from the North American population if the class were larger? Why?
2) What does the Hardy-Weinberg equation predict will occur to the allele frequency of a
randomly reproducing population? Do the class results in Table #4 bear out this
prediction? Why?
3) What was the amount of change of the frequency of the recessive allele in chart five
after five generations of selection?
4) As the frequency of the recessive allele becomes smaller due to natural selection, what
happens to the frequency of heterozygous offspring?
5) The allele for the ability to roll one’s tongue is dominant over the allele for the lack of
this ability. In a population of 500 individuals, 25 percent show the recessive
phenotype. How many individuals would you expect to be homozygous dominant
for this trait?
6) Draw pictures of the graphs of directional, disruptive, and stabilizing selection.
Written Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
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LAB #16, CLASSIFICATION AND PHYLOGENY
LESSON OVERVIEW
The Classification activity reinforces the concept that closely related organisms
have similar traits, and therefore have an ancestry from a common gene pool. Students
construct their own phylogeny and classification system using qualitative appearance,
and quantitative dating. This lab is was initially shown in the American Biological
Teacher.
STRAND
Survivors pass traits to offspring
Populations are the units of evolution
Organisms with similar traits are closely related
Similar organisms have similar genes and DNA
OBJECTIVES; DURING THIS LESSON THE STUDENT SHOULD LEARN
1) Define: phylogeny, phyla, sympatric speciation and allopatric speciation.
2) Organize organisms into taxonomic categories.
3) Develop a phylogeny based upon the fossil record.
PASS SKILLS ADDRESSED
P2.1 Using observable properties, place cells, organisms, and/or events into a biological
classification system.
P2.2 Identify the properties by which a biological classification system is based.
P5.1 Interpret a biological model which explains a given set of observations.
3.2 Species acquire many of their unique characteristics through biological adaptation,
which involves the selection of naturally occurring variations in populations.
Biological adaptations include changes in structures, behaviors, or physiology,
which may enhance or limit survival and reproductive success in a particular
environment.
MATERIALS AND PREPARATION
Use the sheets.
LESSON SEQUENCE
1) Engage the students by dividing them into groups, and have them arrange the
Caminicules in the cut out page from oldest to youngest.
2) The students explore by arranging the Caminicules in Figure #1 into phyla
according to the criteria of those having the most similarities.
3) Explain the concept of most recent ancestors generally having the most advanced
characteristics.
4) The students expand by arranging all of the Caminicules in figure #2 into a
phylogeny.
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87
Back of cut out page
88
LAB # 16, CLASSIFICATION AND PHYLOGENY
OBJECTIVES After this lab the student will be able to;
1) Define: phylogeny, phyla, sympatric speciation and allopatric speciation.
2) Organize organisms into taxonomic categories.
3) Develop a phylogeny based upon the fossil record.
EXPLORE
1) Cut out and arrange the fourteen species in Figure #1 into a hierarchal classification.
A) Combine each numbered species into genera. Use the criteria that members of the
same genera should resemble each other more than other genera. Assign each
genera a number.
B) Using the same criteria, combine genera into Families and Order(s), and assign
each Family and Order a number.
C) Complete Table #1 using the number of each species, Family and Order for your
classification system. Include this table in your lab notebook.
2) Construct a phylogenic tree based upon living species of Caminacules.
Using the living organisms from Figure #1, organize a phylogenic tree in Table #2
that shows descent with modification. At the top of the tree will be the number of
each organism, followed by the Genus, Family, and Order levels. Include this in
your lab notebook.
Figure #1, LIVING CAMINACULES
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Back of cut out page
90
DATA
Table #1, Hierarchal classification of the Caminacules
Class
Caminacule
Order
Family
Genus
Species
Table #2, Phylogeny of Living species
Species
Genus
Family
Order
EXPLAIN
One of the most important concepts in constructing a phylogenic tree is the idea
of most recent ancestor. Closely related species with similar traits and characteristics will
share a common genus and ancestor not shared by other less closely related species.
When a change in a species occurs due to changes in the environment, the term is
sympatric speciation. When changes accumulate due to geographic or reproductive
isolation, allopatric speciation is occurring, causing a split in the family tree or
phylogeny. During this lab the student will construct a classification system for the
Caminacules, and a phylogeny based upon traits and characteristics.
EXTEND
Construct a phylogenic tree based upon the fossil record.
1) Each Caminacule in Figure #2 is identified by a species number, and the age in
millions of years in parentheses.
2) Cut out your Caminacules and in Table #3, place animal #73 in the middle of line 19
(for 19myo). This species gave rise to two new species (58 and 74) which are
placed on line 18 (for 18myo). When complete, glue your critters in place.
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Figure #2 FOSSIL CAMINACULES (numbers in parentheses indicate age in millions of years)
92
Back of cut out page
93
Table #3, Caminacule phylogeny
Millions of years ago
0_____________________________________________________________________________________
1_____________________________________________________________________________________
2_____________________________________________________________________________________
3_____________________________________________________________________________________
4_____________________________________________________________________________________
5_____________________________________________________________________________________
6_____________________________________________________________________________________
7_____________________________________________________________________________________
8_____________________________________________________________________________________
9_____________________________________________________________________________________
10____________________________________________________________________________________
11____________________________________________________________________________________
12____________________________________________________________________________________
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EVALUATE
1) In the space below use the numbers of the Caminacules to create a phylogenic tree
from extinct to modern.
2) Compare your phylogeny to the fossil data. What has changed?
3) Did your phylogeny stay the same after using the fossil data? What changed?
4) What is convergent evolution?
5) From the Caminacule phylogeny, name two examples of sympatric speciation.
6) From the Caminacule phylogeny, name two examples of allopatric speciation.
7) What is evolution?
8) What is the value of the fossil record in determining phylogeny?
9) What causes some species to become extinct, while others thrive?
10) Define allopatric speciation, sympatric speciation, and phylogeny.
Written Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
95
LAB # 17, TRANSPIRATION
LESSON OVERVIEW
The purpose of the transpiration activity is to demonstrate the factors effecting the
transpiration rates of water within plants.
STRAND
Materials are recycled, energy is lost as heat.
OBJECTIVES, After this lab the student will be able to:
1) Describe the characteristics of water that make transpiration possible.
2) Calculate the leaf area of a plant.
3) Measure transpiration rates using a potentometer.
4) Design an investigation to measure factors affecting transpiration rates.
PASS SKILLS ADDRESSED
P1.1 Identify qualitative and quantitative changes in cells, organisms, populations, and
ecosystems given condition (e.g. temperature, mass, volume, time, position,
length, quantity, etc.) before, during, and after an event.
P1.2 Use appropriate tools (e.g., microscope, pipette, metric ruler, graduated cylinder,
thermometer, balances, stopwatches, etc.) when measuring cells, organisms,
populations, and ecosystems.
P1.3 Use appropriate System International (SI) units (i.e., grams, meters, liters, degrees
Celsius, and seconds); and SI prefixes (i.e., micro-, milli-, centi-, and kilo-) when
measuring cells, organisms, populations, and ecosystems.
P3.1 Evaluate the design of a biology laboratory investigation.
P3.2 Identify the independent variables, dependent variables, and controls in an
experiment.
P3.3 Use mathematics to show relationships within a given set of observations (e.g.,
population studies, biomass, probability, etc.).
P4.3 Interpret data tables, line, bar, trend and/or circle graphs.
P4.4 Accept or reject hypotheses when given results of a biological investigation.
P4.5 Evaluate experimental data to draw the most logical conclusion.
P4.6 Prepare a written report describing the sequence, results, and interpretation of a
biological investigation or event.
P4.7 Communicate or defend scientific thinking that results in conclusions.
P4.8 Identify and/or create an appropriate graph or chart from collected data, tables, or
written description (e.g., population studies, plant growth, heart rate, etc.).
P5.1 Interpret a biological model which explains a given set of observations.
P6.1 Formulate a testable hypothesis and design an appropriate experiment relating to the
living world.
P6.2 Design and conduct biological investigations in which variables are identified and
controlled.
P6.3 Use a variety of technologies, such as hand tools, microscopes, measuring
instruments, and computers to collect, analyze, and display data.
P6.4 Inquiries should lead to the formation of explanations or models (physical,
96
conceptual, and mathematical). In answering questions, students should engage in
discussions (based on scientific knowledge, the use of logic, and evidence from
the investigation) and arguments that encourage the revision of their explanations,
leading to further inquiry.
4.1 Matter on the earth cycles among the living and nonliving components of the
biosphere.
MATERIALS
1) Coleus stems or bean stems.
2) Vinyl tubing
3) Graduated pipettes
4) Ring stands
5) Scale
6) Plastic bags, misters, fan, bright light
7) Clock with second hand
LESSON SEQUENCE
Plants your beans about two to three weeks prior to this lesson. An alternative
would be to use celery, and to measure the volume of water removed by the plant.
1) Engage students with capillary tubes to show the limits of capillary action. Xylem
is like a bundle of straws, and the water is pulled out of the plant by transpiration.
2) Explore. Students work with the potentometer to learn how it is used, and how to
measure transpiration rates.
3) Extend. Students design an exercise to measure the effects of a variable such as
wind, humidity, or light intensity.
4) Evaluate. Students perform a lab write up to formally summarize the experiment.
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LAB #17, TRANSPIRATION
OBJECTIVES After this lab the student will be able to;
1) Describe the characteristics of water that make transpiration possible.
2) Calculate the leaf area of a plant.
3) Measure transpiration rates using a potentometer.
4) Design an investigation to measure factors affecting transpiration rates.
EXPLORE
Xylem vessel tension.
1) Take a well watered bean seedling and place the stem under dyed water.
2) Using a razor blade, cut the middle of the stem under water.
3) Using a razor blade, slice 1mm slices from each side of the cut, until you can no longer
see blue dye in the xylem vessels. Record the number of millimeters of dye travel
In Table #1, and on the board.
4) Repeat the cutting process on an unwatered bean seedling. Record the distance of dye
travel in Table #1, and on the board.
5) Calculate the class averages for dye travel, and record on Table #1.
Transpiration rates
1) Fill the potometer with water in the plastic tray. Be sure that there are no air
bubbles.
2) Cut the stem of the plant under water and carefully insert the cut stem into the plastic
tubing end of the potometer. Seal the cutting into the tube with petroleum jelly.
Do not get any petroleum jelly on the cut end of the stem!
3) Set the potometer up on the ring stand and allow it to equilibrate for 5 minutes.
4) Measure the changes in volume by measuring the movement of water in the pipette.
Record the results in Table #2. Calculate the difference and record in Table #2.
5) At the end of the experiment, cut off the leaves, blot off the water, and weigh them.
Record the mass on Table #3 and determine the leaf area. Since a square meter of
bean leaves weighs 160 grams, the area of the leaves can be calculated by
dividing the mass by 160 gms/M2. Record the results on Table #3.
6) To find the water loss per meter2, divide the water loss in Table #2 by the leaf area in
Table #3. Record in Table #4.
7) Collect class transpiration averages from the board and record in Table #5 and table
#6.
DATA
Table #1, Dye Travel In Watered and Unwatered Bean Seedlings.
Seedling
Dye Travel (mm)
Watered
Unwatered
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Class Average
Table #2, Water Volumes in Potometer in mLs.
Time
(min)
0
5
10
15
20
25
30
Volume
(mL)
Difference
(mL)
Difference* = Volume at time X - Volume at time 0
Table #3, Leaf Area
Leaf area, gms/160gms/meter2
Leaf mass (gms)
Table #4, Water loss per leaf Area.
Time
0
10
20
30
Water loss,
mL/m2
ANALYSIS
1) Calculate the rate of water loss per minute by dividing cumulative water loss at the 30
minute reading by 30. Record the results in Table #6.
Table #6, Class Water Movement Rates
Treatment
Water loss at 30 min
Control
Variable
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Transpiration Rate
(mL/m2/min)
2) Using the data from Table #5, graph the class average water loss for each time interval.
Use a best-fit line to display your data, and a key to identify each line.
EXPLAIN
Water has several important roles in plant growth. Water serves the as a proton
donor during photosynthesis, as a structural material by maintaining turgor pressure
within the rigid plant cell walls, and as a source of dissolved minerals and ions such as
calcium and phosphorus. Transpiration is the movement of water from the roots to the
leaves. The water is actually pulled up the stem during transpiration, creating tension
within the water column. Water movement in plants is passive, and no energy is required
from the plant. Four factors move water up the xylem from the roots.
1) Capillary action. Capillary action is due to the adhesive and cohesive forces of
the polar water molecules. Water will only move a short distance until the downward
gravitational force is equal to the upward capillary force.
2) Osmosis/diffusion. Osmosis and diffusion are important to cells that lie several
cells distant from xylem cells. Diffusion supplies very little force to pull the water up the
xylem.
3) Root pressure. Root pressure occurs when the ground is very wet and rarely
contributes much to water movement.
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4) Transpiration. Transpiration is the pulling of the water column in the xylem
as the water evaporates from the leaves.
All of the factors contributing to water movement depend upon the characteristics
of the water molecule itself. Water is a polar molecule with opposite charges at either
end. The opposite ends of the water molecules are attracted to each other and form weak
hydrogen bonds. The hydrogen bonding gives water both adhesive and cohesive
properties. As a water molecule is pulled, it pulls other molecules along. Stomata on the
bottom of leaves control the flow of water within the plant. As the stomata open, water
evaporates from the ground tissue of the leaf and a chain of water molecules is pulled up
the xylem vessels. The pulling of the water column creates a tension in the xylem vessels.
If the water column is broken, and air enters the vessel, the water column collapses and
the xylem vessel is no longer able to pull water from the roots into the leaves.
Many environmental factors will effect transpiration rates. Increases in temperature, light
intensity, and the presence of dry air currents can cause an increase in transpiration rates.
In this lab your will observe both the force of tension in the xylem vessels and calculate
the rate of transpiration per square centimeter of leaf tissue.
EXTEND
1) Design an experiment to measure the efficiency of photosynthesis at either different
temperatures, light intensities, humidity, using the materials provided.
2) Write a specific “if, and, therefore” hypothesis.
3) Design a controlled experiment based upon your hypothesis.
a) Design and write your procedure.
b) Design table and graphs for collecting and interpreting data.
4) Your lab will be scored by the following criteria. Theory 10 pts, hypothesis 10 pts,
procedure
15 pts, data collection 15 pts, data analysis 10 pts, conclusion 10 pts. We will
perform the lab next class period, so bring your lab write up with the theory, hypothesis,
procedure, and tables for data collection.
Generate a hypothesis here;
________________________________________________________________________
________________________________________________________________________
EVALUATE, Write and answer the following questions in your lab notebook.
1) Why did the dye travel further in the dry stem than the watered stem when cut?
2) List the factors that increase transpiration rates from greatest to smallest.
3) What is the source of energy for transpiration?
4) Explain how each of the treatments cause an increase or decrease in transpiration.
5) How does the plant actively control transpiration rates?
6) Define transpiration, cohesion.
Written Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
101
LAB #18, PRIMARY PRODUCTIVITY
LESSON OVERVIEW
The primary productivity lab demonstrates the interaction of producers and
consumers in an aquatic ecosystem. The oxygen concentration is measured in pond water
and samples are placed in the light and in the dark. The oxygen produced by
photosynthesis minus the oxygen consumed by respiration is the primary productivity of
the system. The influence of nitrates and phosphates are also evaluated by the student.
STRAND
Materials are recycled, energy is lost as heat
Energy is located in molecular bonds
Cells are the structural/functional units of life
OBJECTIVES; After this lesson the student will be able to:
1) Define biomass, primary productivity, net productivity.
2) Explain the relationship between productivity and biomass.
3) Measure the respiration rate and calculate the primary productivity of an
aquatic environment.
4) Predict the effect of adding nitrogen and phosphorus to an aquatic ecosystem.
5) Design an investigation to measure factors that influence the net productivity of
an aquatic ecosystem.
PASS SKILLS ADDRESSED
P1.1 Identify qualitative and quantitative changes in cells, organisms, populations, and
ecosystems given condition (e.g. temperature, mass, volume, time, position,
quantity, etc.) before, during, and after an event.
P1.2 Use appropriate tools (e.g., microscope, pipette, metric ruler, graduated cylinder,
thermometer, balances, stopwatches, etc.) when measuring cells, organisms,
populations, and ecosystems.
P1.3 Use appropriate System International (SI) units (i.e., grams, meters, liters, degrees
Celsius, and seconds); and SI prefixes (i.e., micro-, milli-, centi-, and kilo-) when
measuring cells, organisms, populations, and ecosystems.
P3.1 Evaluate the design of a biology laboratory investigation.
P3.2 Identify the independent variables, dependent variables, and controls in an
experiment.
P3.3 Use mathematics to show relationships within a given set of observations (e.g.,
population studies, biomass, probability, etc.).
P3.4 Identify a hypothesis for a given problem in biology investigations.
P4.1 Select appropriate predictions based on previously observed patterns of evidence.
P4.2 Report data in an appropriate manner.
P4.3 Interpret data tables, line, bar, trend and/or circle graphs.
P4.4 Accept or reject hypotheses when given results of a biological investigation.
P4.5 Evaluate experimental data to draw the most logical conclusion.
P4.6 Prepare a written report describing the sequence, results, and interpretation of a
biological investigation or event.
102
P4.7 Communicate or defend scientific thinking that results in conclusions.
P4.8 Identify and/or create an appropriate graph or chart from collected data, tables, or
written description (e.g., population studies, plant growth, heart rate, etc.).
P6.1 Formulate a testable hypothesis and design an appropriate experiment relating to the
living world.
P6.2 Design and conduct biological investigations in which variables are identified and
controlled.
P6.3 Use a variety of technologies, such as hand tools, microscopes, measuring
instruments, and computers to collect, analyze, and display data.
P6.4 Inquiries should lead to the formation of explanations or models (physical,
conceptual, and mathematical). In answering questions, students should engage in
discussions (based on scientific knowledge, the use of logic, and evidence from
the investigation) and arguments that encourage the revision of their explanations,
leading to further inquiry.
4.1 Matter on the earth cycles among the living and nonliving components of the
biosphere.
5.1 The complexity and organization of organisms accommodate the need for obtaining,
transforming, transporting, releasing, and eliminating matter and energy used to
sustain the organisms (i.e., photosynthesis and cellular respiration).
5.2 As matter and energy flow through different levels of organization of living systems
and between living systems and the physical environment, chemical elements are
recombined in different ways by different structures. Matter and energy are
conserved in each change (i.e., water cycle, carbon cycle, nitrogen cycle, food
webs, and energy pyramids).
MATERIALS
1) Dissolved oxygen measurement kits
2) Large test tubes, corks
3) Foil, screen mesh, colored cellophane
4) Grow light
LESSON SEQUENCE
1) Engage the students by having them measure the primary productivity of an
aquatic system using dissolved oxygen kits. The students fill two test tubes with
aquarium water, tightly seal the tubes, them cover one with foil. The difference in
O2 content of the jars is a measure of primary productivity of the aquatic system.
2) The students explore by designing a test to find the effects of variables such as
pollutants to the primary productivity of the system. Some variables that would be
easy to test would be pH (acid rain), fertilizer, herbicides, nitrogen, phosphate,
detergents, light intensity, light wavelength, chicken manure, etc..
3) The students work in groups, and present their findings to the class at the end of
the study.
4) Their work is followed by a formal lab write up using the format from the front of
the manual.
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LAB #18, PRIMARY PRODUCTIVITY
OBJECTIVES After this lab the student will be able to;
1) Define biomass, primary productivity, net productivity.
2) Explain the relationship between productivity and biomass.
3) Measure the respiration rate and calculate the primary productivity of an
aquatic environment.
4) Predict the effect of adding nitrogen and phosphorus to an aquatic ecosystem.
5) Design an investigation to measure factors that influence the net productivity of
an aquatic ecosystem.
EXPLORE
In this lab you will calculate the primary and net productivity of a water sample.
PROCEDURE
1) Fill tubes #1 and #2 to the brim with water and tightly stopper to ensure that no air
bubbles are inside.
2) Cover Tube #2 with foil so that no light can enter.
3) Place the tubes in a large test tube rack under bright light for 5 days.
4) Using the LaMotte kit, measure the dissolved oxygen of the water the tubes came
from. Record your results in Table #1.
5) Place the tubes under the grow light for 24-48 hours, measure the dissolved oxygen
again.
6) Calculate the net productivity of each tube in Table #1, and graph the results.
DATA
Table #1, Concentration of oxygen in mg/Liter
Test Tube
Initial (I)
Final (F)
Primary productivity (F-I)
#1, Control
#2, Dark
7) Subtracting the loss of oxygen due to respiration (Tube #2) we can calculate the net
productivity of each bottle. Record results in Table #2.
Table #2, Concentration of oxygen in mg/Liter.
Test tube
Primary productivity
Respiration (#2)
#1, Control
#2, Dark
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Net productivity (PP-#2)
8) Make a bar graph to show the results of the net productivity of the tubes.
Net productivity of aquarium water
EXPLAIN
The energy for all living systems is stored and transferred in the form of
molecular bonds. These molecular bonds are contained within the organic molecules
(glucose) made during photosynthesis. The dry mass of organic molecules of an organism
is called biomass. The biomass is catabolized during respiration to drive the ATP-ADP
cycle within the mitochondria of eukaryotic cells. When the rate of photosynthesis is
higher than the rate of cellular respiration, more molecular bonds and organic molecules
are being made than are being respired.
The equation for photosynthesis is; 6H2O + 6CO2 —> C6H12O6 + 6O2
The equation for respiration is;
6O2 + C6H12O6 —> 6H2O + 6CO2
Primary productivity is the total increase of biomass in an ecosystem due to
photosynthesis. The net productivity of an ecosystem is the primary productivity minus
the loss of biomass due to cellular respiration. An easier way to calculate productivity
than the change in biomass is by the change in the dissolved oxygen content of the water.
Biologists use the dark bottle test to measure productivity in aquatic ecosystems. A
sample of water is placed in both a light and a dark bottle and placed under light. The
change in O2 concentration in the light bottle measures primary productivity, and the
change in O2 concentration in the dark bottle measures the amount of respiration. The
difference in the concentration of oxygen between the two bottles is the net productivity
of the water.
EXTEND
1) You group is to design an investigation to research the influence of pollutants or
fertilizers to the net productivity of an aquatic system. Some examples of
variables would be fertilizer, herbicides, oil/gasoline, phosphates, nitrogen,
chicken manure, pH (acid rain), pop, light wavelength, light intensity, etc. Be sure
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to visit the Oklahoma Department of Environmental Quality web site, or the EPA
web site to determine levels and concentrations. At the end of your study, your
group will present findings to the class.
2) Write a specific “if, and, therefore” hypothesis.
3) Design a controlled experiment based upon your hypothesis.
a) Design and write your procedure.
b) Design table and graphs for collecting and interpreting data.
4) Your lab will be scored by the following criteria. Theory 10 pts, hypothesis 10 pts,
procedure 15 pts, data collection 15 pts, data analysis 10 pts, conclusion 10 pts.
We will perform the lab next class period, so bring your lab write up with the
theory, hypothesis, procedure, and tables for data collection.
Generate a hypothesis here;
________________________________________________________________________
________________________________________________________________________
EVALUATE Answer the following questions.
1) Why would nitrogen increase productivity?
2) Why would phosphate increase productivity?
3) How could an increase in algae decrease the amounts of oxygen dissolved in water?
4) Would decomposition increase or decrease the concentration of oxygen in the water?
5) Look up eutrophication. How can an increase in biomass cause eutrophication of a
river?
6) Define primary productivity, net productivity, and biomass.
Written Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
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LAB #19, POPULATION GROWTH
LESSON OVERVIEW
The population growth lab demonstrates that populations over-reproduce until a
limiting factor is reached. The lab provides a nice sigmoid curve.
STRAND
Populations over-reproduce
Variation occurs in populations
Communities have inter and intraspecific competition
OBJECTIVES; After this lesson the student will be able to;
1) Define biotic, abiotic, carrying capacity, exponential growth, limiting factors.
2) Describe biotic and abiotic factors that effect population growth.
3) Measure population growth rate of Duckweed.
4) Design and conduct an investigation to measure the factors influencing
population growth.
PASS SKILLS ADDRESSED
P1.1 Identify qualitative and quantitative changes in cells, organisms, populations, and
ecosystems given condition (e.g. temperature, mass, volume, time, position,
length, quantity, etc.) before, during, and after an event.
P1.2 Use appropriate tools (e.g., microscope, pipette, metric ruler, graduated
cylinder,thermometer, balances, stopwatches, etc.) when measuring cells,
organisms, populations, and ecosystems.
P1.3 Use appropriate System International (SI) units (i.e., grams, meters, liters, degrees
Celsius, and seconds); and SI prefixes (i.e., micro-, milli-, centi-, and kilo-) when
measuring cells, organisms, populations, and ecosystems.
P3.1 Evaluate the design of a biology laboratory investigation.
P3.2 Identify the independent variables, dependent variables, and controls in and
experiment.
P3.3 Use mathematics to show relationships within a given set of observations (e.g.,
population studies, biomass, probability, etc.).
P3.4 Identify a hypothesis for a given problem in biology investigations.
P4.1 Select appropriate predictions based on previously observed patterns of evidence.
P4.2 Report data in an appropriate manner.
P4.3 Interpret data tables, line, bar, trend and/or circle graphs.
P4.4 Accept or reject hypotheses when given results of a biological investigation.
P4.5 Evaluate experimental data to draw the most logical conclusion.
P4.6 Prepare a written report describing the sequence, results, and interpretation of a
biological investigation or event.
P4.7 Communicate or defend scientific thinking that results in conclusions.
P4.8 Identify and/or create an appropriate graph or chart from collected data, tables, or
written description (e.g., population studies, plant growth, heart rate, etc.).
P5.1 Interpret a biological model which explains a given set of observations.
P6.1 Formulate a testable hypothesis and design an appropriate experiment relating to the
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living world.
P6.2 Design and conduct biological investigations in which variables are identified and
controlled.
P6.3 Use a variety of technologies, such as hand tools, microscopes, measuring
instruments, and computers to collect, analyze, and display data.
P6.4 Inquiries should lead to the formation of explanations or models (physical,
conceptual, and mathematical). In answering questions, students should engage in
discussions (based on scientific knowledge, the use of logic, and evidence from
the investigation) and arguments that encourage the revision of their explanations,
leading to further inquiry.
4.3 Living organisms have the capacity to produce populations of infinite size, but
environments and resources limit population size (e.g., carrying capacity and
limiting factors).
MATERIALS AND PREPARATION
Duckweed, Petri dishes, pond water, light source.
LESSON SEQUENCE
This lab is a long term experiment that can be started at the beginning of the year but
must be started at least a month before it is due. Pond water is a good growth medium,
but any fertilizer in deionized water will do.
1)Students can be engaged by graphing population growth, or measuring bacterial
growth in milk using the methyl blue technique. This is a long term exploration
that will require about a month to conduct.
2) Students explore by choosing one of several variables to study. Variables can be space,
nutrients (fertilizer, nitrogen, phosphate, detergents, etc.), light intensity, or light
wavelength.
3) Students evaluate their work by presenting the results to the class. Each presentation
should include a hypothesis, the variables studied, the controls used, a graph of
the results, and any conclusions.
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LAB# 19, POPULATION GROWTH LAB
OBJECTIVES. After this lab the student will be able to;
1) Define biotic, abiotic, carrying capacity, exponential growth, limiting factors.
2) Describe biotic and abiotic factors that effect population growth.
3) Measure population growth rate of Duckweed.
4) Design and conduct an investigation to measure the factors influencing
population growth.
PROCEDURE
1) Take a plastic Petri dish and write your name and hour on the bottom.
2) The duckweed floats on the surface of the water and is made of 1-4 lobes. Each lobe is
considered a plant.
3) Observe the plant under the dissecting microscope and sketch what you see in Diagram
#1.
4) Pour 15 ml of pond water/growth media in your Petri dish and select 10 plants (lobes)
from the aquarium stock of duckweed.
5) Cover the Petri dish and place under the growth light.
6) Set up a chart to record your observations of the population of lobes of duckweed over
two weeks time. Record the number of lobes in your original sample of
duckweed.
DATA
Diagram #1, Duckweed structure
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Table #1, Duckweed growth
Day
0
2
4
6
8
10
12
14
# Lobes
ANALYSIS
1) At the end of two weeks, make your final count of lobes.
2) Graph the results with the independent variable on the X axis, and the dependent
variable on the Y axis.
Graph #1, Duckweed lobe growth
EXPLAIN
Organisms reproduce at a higher rate than their environment can support. Plants
produce thousands of seeds, insects produce hundreds of eggs. This over-reproduction
causes competition among the members of the population for limited natural resources.
The population will grow until a limiting factor is reached and the death rate is equal to
the death rate.
Our study will have two parts. During the first part you will measure the growth
of a common aquatic plant, duckweed. You will set up a growth culture and graph the
growth of the duckweed under normal conditions. In the second part of the lab, you will
design an approach that will test some variables that affect the growth rate of duckweed.
EXTEND
1) With your team members, make a list of 5 factors that limit the growth of
duckweed in the Petri dish. You will have to be very specific.
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2) Design an experiment to remove a limiting factor and measure Duckweed growth.
3) Write a specific “if, and, therefore” hypothesis.
4) Design a controlled experiment based upon your hypothesis.
a) Design and write your procedure.
b) Design table and graphs for collecting and interpreting data.
5) Your lab will be scored by the following criteria. Theory 10 pts, hypothesis 10 pts,
procedure 15 pts, data collection 15 pts, data analysis 10 pts, conclusion 10 pts.
We will perform the lab next class period, so bring your lab write up with the
theory, hypothesis, procedure, and tables for data collection.
Generate a hypothesis here;
________________________________________________________________________
________________________________________________________________________
EVALUATE
1) What is a limiting factor?
2) How can the carrying capacity of an environment be increased?
3) What is the relationship between carrying capacity and evolution?
4) Did your population grow at the same rate, and the same way that your group
predicted?
5)Define biotic, abiotic, carrying capacity, exponential growth, limiting factors.
Written Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
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LAB #20, ANIMAL BEHAVIOR
LESSON OVERVIEW
Animal behavior is how animals respond to changes in the environment. The
primary behaviors are responses to resources, members of their species, and members of
other species.
STRAND
Communities have intra and interspecific competition
The environment selects successful phenotypes
OBJECTIVES; DURING THIS LESSON THE STUDENT SHOULD LEARN
1) Define kinesis, taxis, orientation behavior, agonistic behavior, dominance
display, and mating behavior.
2) Collect data measuring the environmental selection of animals.
3) Design and conduct an investigation of animal behavior and habitat selection.
PASS SKILLS ADDRESSED
P1.1 Identify qualitative and quantitative changes in cells, organisms, populations, and
ecosystems given condition (e.g. temperature, mass, volume, time, position,
length, quantity, etc.) before, during, and after an event.
P3.2 Identify the independent variables, dependent variables, and controls in and
experiment.
P3.3 Use mathematics to show relationships within a given set of observations (e.g.,
population studies, biomass, probability, etc.).
P3.4 Identify a hypothesis for a given problem in biology investigations.
P4.1 Select appropriate predictions based on previously observed patterns of evidence.
P4.2 Report data in an appropriate manner.
P4.3 Interpret data tables, line, bar, trend and/or circle graphs.
P4.4 Accept or reject hypotheses when given results of a biological investigation.
P4.5 Evaluate experimental data to draw the most logical conclusion.
P4.7 Communicate or defend scientific thinking that results in conclusions.
3.2 Species acquire many of their unique characteristics through biological adaptation,
which involves the selection of naturally occurring variations in populations.
Biological adaptations include changes in structures, behaviors, or physiology,
which may enhance or limit survival and reproductive success in a particular
environment.
4.2 Organisms both cooperate and compete in ecosystems (i.e., parasitism and
symbiosis).
6.2 Responses to external stimuli can result from interactions with the organism’s own
species and others, as well as environmental changes; these responses can be
either innate or learned. Broad patterns of behavior exhibited by animals have
changed over time to ensure reproductive success.
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MATERIALS
Each lab group will require;
1) 10 sow-bugs
2) 1 environmental chamber
3) Cover
4) Paper towels or filter paper
5) Vinegar, ice, salt water
LESSON SEQUENCE
1) Engage students by having them observe the sow-bugs for five minutes and
qualitatively recording behaviors.
2) The students can then explore by including variables. Give the students flashlights,
paper, screen, colored cellophane, ice, etc. to make qualitative observations. Ask
them to look for social interaction and communication. The students should
realize that the sow-bugs are not just randomly moving, but are searching for
limited resources.
3) The students elaborate by designing a test to measure specific behaviors. The Chi
-square method of analyzing data is used to evaluate the sow-bug preferences.
4) Students evaluate their work by presenting the results to the class. Each presentation
should include a hypothesis, the variables studied, the controls used, a graph of
the results, and any conclusions.
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LAB #20, ANIMAL BEHAVIOR
OBJECTIVES, After this lab the student should be able to;
1) Define kinesis, taxis, orientation behavior, agonistic behavior, dominance
display, and mating behavior.
2) Collect data measuring the environmental selection of animals.
3) Design and conduct an investigation of animal behavior and habitat selection.
EXPLORE
1) Put five sow-bugs in a Petri dish and watch them for five minutes. Have each group
member choose one bug to observe. Count how many times it stops, changes
directions, or interacts with another sow-bug. Is the movement random? Record
your findings in the box below.
2) Choose a variable and look at the response of the sow-bug. Was there a measureable
response?
Chart #1, Sow bug behaviors
Observed behaviors;
Stops___________________________
Directional changes_______________
Interaction_______________________
Observed behaviors with variable;
Stops___________________________
Directional changes_______________
Interaction_______________________
EXPLAIN
Animal behaviors allow the animal to quickly respond to changes in the
environment. Behaviors are either innate or learned. Orientation behaviors place the
animal in a favorable environment. During taxis animals move away or towards a
stimulus of heat, chemicals, moisture light, or sound. Kinesis is random movement or
searching behavior. Agonistic behavior is exhibited when animals respond to each other
by aggressive or submissive responses, and is characteristic of animals that have social
stratification. Mating behaviors involve finding, courting and mating with members of
the same species.
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EXTEND
We have selection chambers made from Petri dishes. Choose a variable such as
temperature, pH, or moisture to evaluate environmental choice.
Procedure
1) Number one part of the choice chamber “I” and the other part of the chamber “II”.
Place a piece of filter paper in the bottom of “I” and “II”. Chamber II will b either
“moist”, “dry”, “cold” or “acidic”.
2 )Place 5 sow-bugs in chambers I and II and cover. Let sit undisturbed for 1
minute. Uncover the chamber every 60 seconds and count the bugs in each half.
Record your data in Table #1. At the end of ten minutes total the number of bugs
in each chamber and record the total number in chamber II in Table #2.
DATA
Table #1, Number of Sow-bugs in Each Chamber
Time
0
1
2
3
4
5
6
Average
7
8
9
10
Total
Polies in
chamber
I
Polies in
chamber
II
ANALYSIS
1) Average the number of sow-bugs in each chamber.
2) We would expect chance to create a distribution close to ½ and ½ , with the sowbugs spending an equal amount of time in each chamber. Generate a null hypothesis
for the data in Table #1. The null hypothesis will state that there is no significant
difference between the number of bugs in the dry chamber and in the experimental
chamber.
State your null hypothesis here;______________________________________________
_______________________________________________________________________
3) Generate a X2 analysis of the data in Table #2.
The formula for the Chi-Square is
X2 =  (o - e)2
e
Where;
o = observed number of individuals, e = expected number of individuals
 =the sum of the value
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Table #2, X2
Variable
Average
#Observed(o)
Expected (e)
(control)
(o - e)2
(o - e)
(o - e)2
e
Moist
Acidic
Now determine the critical value from the table below. In science we use a probability
(amount of error) of 0.05, and the degree of freedom is one less than the number of
categories. In this case we have two categories (control and variable) so we have one
degree of freedom.
Critical values chart
Degrees of Freedom
1o
2o
3o
4o
5o
0.05
3.84
5.99
7.82
9.49
11.1
0.01
6.64
9.21
11.3
13.2
15.1
0.001
10.8
13.8
16.3
18.5
20.5
Probability
EVALUATION
1) What is the evolutionary advantage of taxis?
2) What is the evolutionary advantage of kinesis?
1) Sow-bugs are kind of dumb, and have a short memory span. How do kinesis and
taxis allow the organism to respond to changes?
2) Why do we perform a Chi-square analysis of the Sow-bug data, instead of
variance or average?
3) Look up sow bugs on the internet. What kind of organism are they?
What are their closest relatives? What characteristics do they share with other
members of the same phylum?
Written Conclusion
Write a one paragraph conclusion. In your conclusion state the purpose of the activity, the
methods used, the results you observed, and the significance of the results.
116