Biology
STAAR-EOC
KEY
Biology Review
Activity Booklet
Table of Contents
STAAR-EOC
Table of Contents
Activity A - Biomolecules and Cellular Transport
3
Activity B - Cellular Energy
9
Activity C - Cell Structure and Virus
16
Activity D - Cell Cycle, Mitosis, Meiosis,
DNA Structure and Replication
24
Activity E - Protein Synthesis and Point Mutations
32
Activity F – Genetics
40
Activity G - Taxonomy and Stability of Environment
48
Activity H - Plants, Nitrogen & Carbon Cycles,
and Relationships of Organisms
58
Additional Notes - Things I need to remember
71
Credits
79
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Biology
Biomolecules & Cellular Transport
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Activity A
Biomolecules & Cellular Transport
Station 1
Biomolecules Content Frame & Card Sort
1. Locate the biomolecule characteristics cards and the
summarizing biomolecules content frame. Examine
each card and determine the correct placement of
each card on the content frame. Then fill in the
Biomolecules Content Frame below.
Biomolecules Content Frame
Macromolecule
(Polymer)
CARBOHYDRATES
Contain
the
Elements
C, H, O
LIPIDS
C, H, O
PROTEINS
C, H, O, N
NUCLEIC ACIDS
Review
C, H, O, N, P
Building
Blocks
Examples…
(Monomer)
Monosaccharide
Monosaccharides:
glucose, fructose,
honey
Disaccharides:
sucrose, maltose,
table sugar
Polysaccharides:
starch, cellulose,
glycogen, pasta,
potatoes, rice
Functions
Picture
Monosaccharides and
Disaccharides: Provide
Energy
Polysaccharides: Store
Energy
Plants store it as
STARCH
Animals store it as
GLYCOGEN
Long term energy
storage and
insulation.
Fats
Repel or retain
1 glycerol
Waxes
water.
3 Fatty Acids
Phospholipids
Structure in cell
Steroids
membranes.
Helps to control cell
functions.
Aid in movement.
Provide structure.
Found in
Controls chemical
muscles and
reactions.
bones.
Amino Acids
Regulates cell
Enzymes/Biolog
(20)
processes.
ical Catalyst
Transports
Hemoglobin
materials.
Antibodies
Helps to fight
disease.
Nucleotides
Carries the
DNA
instructions that
(Deoxyribonucl
control the activities
eic acid)
of a cell
RNA
(Ribonucleic
Acid)
Carries the
instructions that
make proteins.
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Biomolecules & Cellular Transport
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Station 2
Analyzes of Macromolecules
Locate the three structural formula cards for glucose,
lipid, and protein. Use the information on the cards to
answer the questions below.
1. Which elements do all biomolecules have in common?
Carbon, hydrogen, and oxygen
2. Which element does protein contain that lipids and
carbohydrates lack? Nitrogen
3. Give dietary examples for the following organic
compounds:
-Protein: Poultry, Beef, Dairy, Cheese, Legumes, Nuts,
Fish, Eggs
-Carbohydrates: Wheat, Fruits, Vegetables, Grains,
Bread, Pasta
-Lipids: Oils, Waxes, Butter, Fats
4. Most biomolecules are macromolecules. How do a
biomolecule’s size and the number of bonds it
contains affect the amount of energy that is
available? Hint – Where is energy stored and how
is it released?
As the molecule size increases, so does the number
of chemical bonds needed to hold the structure
together. These bonds contain energy, which
enables the molecule to perform its functions. The
more energy contained within the molecule, the
more work the structure can do once the energy is
released. Energy is released when the bonds
holding the atoms together are broken.
Station 2: Part 2
Using the biomolecule flash cards, match the
appropriate definition with the word or phrase.
4
Biology
Biomolecules & Cellular Transport
*Check your
finished*
STAAR-EOC
answers
with
key
when
Key on countertop
5. Which body system breaks polymers into
monomers for the body to use and store? Digestive
Station 3
Analyzes of Osmosis
Review
5
Biomolecules & Cellular Transport
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1. Below is a copy of the data tables sheet you
will find at the station table. Copy onto it the
“before” measurements from the sheet at the
station. These measurements indicate the
length and mass of the potato cores when
freshly cut.
Using the forceps, remove the potato core from
Beaker A (blue liquid) and pat it dry with a paper
towel. With the metric ruler, measure the length of the
potato core to the nearest millimeter. Record the
results in the “after submersion” row of Table 1. Then
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Biology
Biomolecules & Cellular Transport
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use the metric balance to determine the mass of the
potato core to the nearest gram. Record the results in
the “after” row of Table 1. Return the potato core to
the sucrose solution in Beaker A.
Repeat these procedures for the potato cores in
Beaker B (red liquid) and the Distilled Water beaker
(clear liquid). Record the results in Tables 2 and 3,
respectively.
Determine the differences between the before and
after measurements in each column, and record your
findings in the “gain or loss” rows.
2. Using the information recorded in the data
tables, draw arrows on the beakers below to
illustrate what happened to the potato cores
in each of the different solutions.
3. Determine which beaker contains a
hypertonic solution, which contains a
hypotonic solution, and which contains an
isotonic solution. Label each beaker below
with the name of the solution it contains.
Hypertonic
Type of Solution
Isotonic
Hypotonic
Type of Solution
Type of Solution
4. If a fresh potato core is placed in a solution
that contains more sucrose than the solution
in Beaker A, predict what will happen to the
potato core’s mass. Explain your answer.
Review
7
Biomolecules & Cellular Transport
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The potato core will lose more mass than any
of the other potato cores because more water
will diffuse from it.
5. Human body cells are constantly moving water into
and out of themselves. Under what conditions can a
human body cell achieve homeostasis?
A cell would achieve homeostasis when the number of
water molecules outside the cell is the same as the
number of water molecules inside the cell.
6. Using the pictures below of a blood cell, answer the
following questions.
a. Which cell above is in a hypotonic solution?
_3__
b. Which cell above was placed in saltwater?
_1___
c. Which cell above is maintaining homeostasis?
_2___
Station 4:
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Biomolecules & Cellular Transport
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Active Transport
1. Use your mobile learning device to scan the QR code
below. Watch the video about Active Transport until
3:40. Then answer the following questions.
a. List out the ways that Active Transport differs
from Passive Transport.
Passive Transport
Active Transport
Does not require
Requires energy to
energy. Includes
transport molecules
diffusion, osmosis, and
against the
facilitated diffusion.
concentration gradient.
b. Explain the process of Active transport and
make sure to use the following terms: protein
pump, concentration gradient, ATP, ADP,
solute, solution, semi-permeable
membrane
Active transport may be needed to move solute
molecules out of a solution and into a cell. Molecules
that are transported against the concentration gradient
require ATP energy to cross the semi-permeable
membrane. ATP is converted to ADP to release energy
for protein pumps to transport these molecules.
Active transport is mainly used to bring vitamins, minerals,
and ions across the cell membrane. For example, many
plants use active transport to bring minerals from the soil into
the roots of the plant. Circle the correct answer: The soil is
Review
9
Biomolecules & Cellular Transport
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LOW/HIGH in minerals and the roots are LOW/HIGH in
minerals.
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Biology
Cell Structure & Viruses
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Activity B
Cellular Energy
Station 1
Analyzes of Photosynthesis and
Cellular Respiration
Locate the Photosynthesis and Cellular Respiration Formula
sheet and the envelope with the Photosynthesis and Cellular
Respiration Formula cards.
1. Select the cards that show the reactant and product
parts of the formulas for photosynthesis and cellular
respiration. Place the appropriate card over the correct
box on the sheet. Continue until you have covered all
the boxes.
2. Write the formulas for photosynthesis and cellular
respiration in the space below.
Chemical Equation for Photosynthesis
6H2O + 6CO2 + light energy  C6H12O6 + 6O2
Chemical Equation for Cellular Respiration
C6H12O6 + 6O2  6H2O + 6CO2 + ATP
Bromothymol blue is an indicator that
changes from blue to yellow in the
presence of an acid. When you
exhale through a straw into a test tube
of Bromothymol blue and water, the
water will turn yellow because the
carbon dioxide being exhaled
combines with the water to form a
weak carbonic acid.
H2O + CO2 → H2CO3 (carbonic acid)
Review
11
Cell Structure & Viruses
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In an experiment, four test tubes were filled with a mixture of
Bromothymol blue and water. The first test tube contains only
the liquid. An aquatic plant was added to the second test
tube, and a snail to the third one. The last test tube contains
both an aquatic plant and a snail.
The four test tubes were placed in sunlight for 48 hours.
When the test tubes were observed at the end of the 48
hours, the following changes had occurred.
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Cell Structure & Viruses
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1. What cellular process took place to cause the color
change from blue to yellow in Tube S-3 containing
water, Bromothymol blue, and a snail?
The process that caused the color change is called cellular
respiration. The Bromothymol blue indicator changes from
blue to yellow in the presence of an acid. In this case, the
acid resulted from the organism’s cellular respiration
process. During this process, the organism exhales carbon
dioxide, which combines with water to form a weak carbonic
acid, which in turn changes the color of the water from blue
to yellow.
H2O + CO2  H2CO3
2. Why did the other tubes containing water,
Bromothymol blue, and plants not change color?
The plants were going through the process of
photosynthesis, which uses up carbon dioxide in the water. If
carbon dioxide is not present, the weak carbonic acid cannot
form, and the solution does not turn acidic. Therefore, the
Bromothymol blue indicator remains blue.
Four more test tubes were set up the same as the original
four. These test tubes were placed in a dark room for 48
hours. At the end of the 48 hours, the following changes were
observed.
The water in three of the test tubes (D-2, D-3, and D-4)
turned yellow, as shown above.
Review
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Cell Structure & Viruses
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3. What process caused the liquids to change from blue
to yellow?
The process is called cellular respiration.
4. What reactants in the formula were responsible for the
color change?
The reactants responsible for the change are CO2 and
O2.
Examine the two test tubes below.
5. Explain the cellular processes illustrated by these two
test tubes, including energy conversions and any new
molecules that result.
The two cellular processes illustrated by the test tubes are
cellular respiration and photosynthesis. During cellular
respiration, the reactants – glucose (sugar) and oxygen –
combines together to form new products: carbon dioxide
molecules and water molecules. Adenosine triphosphate
(ATP) is produced as the form of energy that can be used for
other cellular processes. During photosynthesis, light energy
(sunlight) combines with the reactants – water and carbon
dioxide – to form new products: glucose (sugar) and oxygen.
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Cell Structure & Viruses
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Station 2
Comparing Photosynthesis and
Cellular Respiration
Locate the Comparing Photosynthesis and Cellular Respiration
Venn diagram and the envelope with the Photosynthesis and
Cellular Respiration cards. Determine which cards represent
facts about cellular respiration and which represent facts
about photosynthesis. Some cards may represent facts
common to both processes.
Place the cards in the correct area of the Venn diagram and
record your placements below.
Review
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Cell Structure & Viruses
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Station 3
Cellular Energy Concept Map
Locate the Cellular Energy Concept Map and the envelope
with the Cellular Energy cards. Place the cards in the correct
area of the diagram and record your placements below.
6.
Analyze the map. Explain in a series of steps the
transfer of energy from sunlight to a molecule of ATP.
Be sure to include the processes of photosynthesis and
cell respiration.
Photosynthesis takes the energy from sunlight and
uses it to put together large sugar molecules from the
raw ingredients of CO2 and H2O. Cellular respiration
occurs when organisms break down large sugar
molecules to use energy to do work and release the
waste products of CO2 and H2O.
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Cell Structure & Viruses
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7. What results from the removal of a phosphate group
from ATP?
Energy is the expected result. Additionally, ATP can
either become ADP (Adenosine Di-phosphate) or AMP
(Adenosine Mono-Phosphate)
8.
A. Which organelle is used for aerobic respiration?
Which organisms undergo this process?
Mitochondria. All living organisms.
B. Which organelle is used for photosynthesis? Which
organisms undergo this process?
Chloroplast. Protists, Plants, Bacteria
Review
17
Cell Structure & Viruses
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Activity C
Cell Structure & Viruses
Station 1
Comparing Prokaryotic and Eukaryotic Cell
Structure and Function
1. Locate the Prokaryotic and Eukaryotic Cell
Comparison Table and the envelope containing
the Cell Structure and Function cards. Remove
the cards from the envelope and place them in
the correct column on the table. Note that there
are three copies of each card; this is because
some cards may belong with more than one cell
type.
2. When you have finished placing the
cards on the table, record your
placements on the table below.
Prokaryotic and Eukaryotic Cell Comparison Table
DNA
Cell wall
Ribosomes
Cell membrane
18
Chloroplast
Golgi body
Nucleus
Ribosomes
Mitochondrion
DNA
Cell membrane
Endoplasmic
reticulum
Lysosome
Cell wall
Golgi body
Nucleus
Ribosomes
Mitochondrion
DNA
Cell Membrane
Endoplasmic
reticulum
Lysosome
Biology
Cell Structure & Viruses
STAAR-EOC
Station 2
Comparing Prokaryotic and Eukaryotic Cell
Characteristics
1. Locate the Characteristics of Prokaryotic and
Eukaryotic Cells cards and accompanying Venn
diagram. Make a comparison between prokaryotic and
eukaryotic cells by placing each card in the appropriate
place on the Venn diagram.
2. Record your Venn diagram placements on the table
below.
DNA floats freely
around inside the cell.
DNA found inside the
cell.
Exhibits higher levels
of division of labor.
Reproduces asexually,
usually by fission or
budding.
Ribosomes found
within the cell.
Ten times larger than
the other cell type.
Found in organisms
that belong to the
Kingdoms
Archaebacteria and
Eubacteria.
Exists only as singlecelled organisms.
Some can move
around using a
flagellum.
Some organisms with
the cell type produce
endospores during
extreme conditions.
Review
Found in organisms
that belong to the
domain Eukaryota.
Some organisms are
unicellular; others are
multicellular.
DNA found within a
membrane-covered
nucleus.
Cell’s organelles are
surrounded by a
membrane.
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Cell Structure & Viruses
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Station 3
Determining Unknown Cells
1. Locate the envelope that contains the Unknown
Cell Types cards. Determine the type of cell each
card represents and record your results below by
putting a “”.
Prokaryotic
Unknown
A
Bacteria
Eukaryotic
Protist
Fungus
Plant
Animal


B

C


D
E

F

G

H
I

J
K




2. Select one of the Unknown Cell Types cards and
justify how you decided to classify it as either
prokaryotic or eukaryotic.
Unknown___________
Prokaryotic or Eukaryotic?________________
Justify…
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Cell Structure & Viruses
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Station 4
Comparing Virus and Cell Structures
1. Locate the Structures of Viruses and Cells sheet at
this station. Carefully examine the structures of
the plant cell, animal cell, bacteriophage virus,
and influenza virus. Then fill in the Comparing
Virus Structures to Cell Structures Venn diagram
below.
2. Scientists consider viruses to be nonliving. Based on
the information you used to fill in the Venn diagram,
would you support or refute this statement? Explain
your position in the space below.
According to the information in the Venn diagram, the only
structure or component that a virus and cell have in common
is nucleic acid. The virus lacks all the other cellular
structures, and without them; it cannot exist, thrive, and
reproduce on its own. Thus unlike living cells, viruses do not
reproduce: They replicate by controlling the DNA and protein
production of a living cell.
Review
21
Cell Structure & Viruses
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3. Some disinfectants, like the one pictured below, claim
that they are effective at killing viruses. Does your
knowledge of the structures and functions of a virus
support or refute this claim? Can viruses really be
“killed”? Explain your position in detail below.
Viruses do not exhibit characteristics of a living
organism and are there for considered to be nonliving.
The product’s claim that it “kills” viruses is
questionable since only living things can be killed. A
virus’ structure may be destroyed, rendering the virus
incapable of entering a living cell to make copies of
itself, but it is inaccurate to say a virus can be killed.
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Cell Structure & Viruses
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Station 5
Analyzing the Lytic Cycle
Locate the Lytic Infection Cycle sheet and the envelope
containing the Lytic Infection cards. Place the cards in the
proper sequence on the Lytic Infection Cycle sheet to
represent how a virus can infect a living cell and cause the
cell to replicate the virus. Draw the sequence of events below.
Review
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Cell Structure & Viruses
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Station 6
Analyzing the Lysogenic Cycle and HIV
1. Locate the Lysogenic Infection Cycle sheet. Not all
viruses replicate through lytic infection. Some viruses
replicate by another method, called lysogenic infection.
a. Just like in the lytic cycle, the virus injects DNA into
the host cell. However, what is different about the
next step(s) of the lysogenic cycle?
During the lysogenic cycle the virus’s nucleic acid
integrates into the host cell’s genetic material, and
a provirus is formed and replicated each time the
host cell reproduces. The host cell will not be killed
until the lysogenic cycle activates.
b. Viruses that replicate using the lysogenic cycle may
not cause any damage to the cell for weeks,
months, or years. Then the virus DNA begins a
process of replication similar to that found in lytic
infection and the virus becomes “active”. Can you
think of viruses that may linger in a human for
years before the person shows symptoms? If so,
name the virus(s).
Answers could include:
1. Herpes simplex
2. Shingles
3. Warts
4. HIV
5. Dengue Hemorrhagic Fever
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Cell Structure & Viruses
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c. The human immunodeficiency virus (HIV) replicates
by the lysogenic infection method, attacking the
cells of our immune system. Why do you think a
person infected with HIV has difficulty fighting
pathogens, such as the common cold or
pneumonia?
HIV replicates by lysogenic infection, meaning that
the virus’ DNA and the immune system cell’s DNA
combine. Once the virus has replicated, it breaks
out of the host cell by a process called lysic. The
newly replicated viruses repeats the process with
other immune system cells, destroying them and
eventually weakening the immune system to the
point that it is unable to fight off infection.
d. Vaccines, deactivated pieces of pathogens,
stimulate the immune system to defend against the
actual pathogen. Vaccines are used to prevent
polio, measles, chicken pox and mumps. Explain
why vaccines are not effective in preventing the
common cold or HIV viruses. (hint: mutations)
Generally, there are so many different viruses which
can cause the common cold. They are similar but
over time mutations have an assortment of varieties
which exist.
Review
25
Cell Cycle, Mitosis, Meiosis, Meiosis, & DNA Structure/Replication
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Activity D
Cell Cycle, Mitosis, Meiosis,
& DNA Structure /Replication
Station 1
Cell Cycle Characteristics
1. Locate the Eukaryotic Cell Cycle sheet and review the
information on the sheet. Remove the Cell Cycle
Characteristics cards from the envelope. Place each
card on the part of the cell cycle that corresponds to
the information on the card.
Card
number
M
2
4
8
Stages in the Cell Cycle
G1
G0
S
1
5
3
7
G2
9
6
2. What must happen to a eukaryotic cell before it can go
from the G1 phase to the S phase?
The cell must grow and conduct normal cell activities in
preparation for the replication of the DNA. Certain cell
components, such as the centrosomes, duplicate.
3. What happens to a cell in the G0 phase?
It may remain in the G0 phase and carry out normal
functions. It can be stimulated to reenter the cycle if needed
or it may be terminated.
4. What purpose do checkpoints serve in the cell cycle?
The G1/S checkpoint confirms the presence of all necessary
conditions, such as nutrients and enzymes required for DNA
replication. If the conditions are not favorable for DNA
replication, the cell is arrested in the cycle.
The G2/M checkpoint confirms that the DNA has been
replicated correctly and is ready to go through mitosis and
cytokinesis.
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Biology
Cell Cycle, Mitosis, Meiosis, Meiosis, & DNA Structure/Replication
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Station 2
Comparison of Eukaryotic Mitosis and Cytokinesis
1. Arrange the Phases of Eukaryotic Mitosis and
Cytokinesis cards in the order they follow during cell
division. Next, remove the Plant and Animal Cell
Mitosis and Cytokinesis cards from their envelope and
match them to the correct stages.
2. Locate the Mitosis in an Onion Root Tip sheet. This
sheet shows cells in various stages of mitosis. Count
the number of cells in each phase of mitosis and enter
the numbers in the table below.
Phase of Mitosis
Interphase
Prophase
Metaphase
Anaphase
Telophase
# of Cells in the Phase
24
3
2
1
0
3. Which phase showed the largest number of active
cells? Explain why this phase, of all the phases, would
most likely have the most abundant number of active
cells.
Interphase has the largest number of active cells. Cells in
an organism are dividing only when the organism needs to
replace damaged cells or when the organism is actively
growing. The necessary resources must be available before
mitosis can begin again.
4. Were some of the cells difficult to classify into a
particular stage of mitosis? Explain why or why not.
Yes, because the process of mitosis is continuous, and
there are no sudden pauses in the process, such as from
prophase to metaphase. The process continues without
stopping.
Review
27
Cell Cycle, Mitosis, Meiosis, Meiosis, & DNA Structure/Replication
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5. Explain what can happen to a cell that can cause it to
become a cancer cell.
There are genes that tell the cell how fast to divide
and when to stop. If these genes are mutated, the
mutation can cause the cell cycle too go to fast – like
running down a hill to fast to be able to stop. The
cancer cells divide too quickly and pile up in one area
– this is called a tumor.
6. What is the relationship between mitosis and growth
in an organism?
Mitosis is the process that enables an organism to
grow. Growth is the physical increase in size and
weight of an organism over a period of time. As cells
divide and grow to maturity in the G1, they cause the
organism to physically grow.
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Biology
Cell Cycle, Mitosis, Meiosis, Meiosis, & DNA Structure/Replication
Review
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Cell Cycle, Mitosis, Meiosis, Meiosis, & DNA Structure/Replication
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Station 3
Mitosis and Meiosis Comparison
1. Locate the Mitosis vs. Meiosis sheet and review the
comparison charts.
2. Circle the type of cell division(s) in which you would
observe the following:
a.
two new cells are formed from the
original
Mitosis
Meiosis
b.
four new cells are formed from the
original
Mitosis
Meiosis
c.
cells with a reduced number of
chromosomes are formed
Mitosis
Meiosis
d.
chromosome number is maintained
Mitosis
Meiosis
e.
results in forming somatic body cells
Mitosis
Meiosis
f.
results in forming gamete sex cells
Mitosis
Meiosis
g.
each parent cell divides only once
Mitosis
Meiosis
h.
each parent cell divides twice
Mitosis
Meiosis
i.
associated with growth and asexual
reproduction
Mitosis
Meiosis
j.
associated with sexual reproduction
Mitosis
Meiosis
k.
daughter cells are identical to parent
and each other
Mitosis
Meiosis
l.
daughter cells are different from the
parent and each other
Mitosis
Meiosis
m. begins diploid (2n) and ends haploid
(1n)
Mitosis
Meiosis
n.
begins diploid (2n) and ends diploid
(2n)
Mitosis
Meiosis
o.
crossing over occurs, whereby genes
“switch” chromosomes
Mitosis
Meiosis
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Circle the appropriate statements below for
each diagram:
2n or n
23 or 46 chromosomes
Identical/Different
Sexual/Asexual
Review
2n or n
23 or 46 chromosomes
Identical/Different
Sexual/Asexual
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Cell Cycle, Mitosis, Meiosis, Meiosis, & DNA Structure/Replication
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Station 4
DNA Structure
1. Locate the envelope containing the DNA Bases cards.
Use the cards to complete the DNA molecule on the
DNA Strands sheet. Then record the information on
the sheet below.
2. What are the components of a DNA molecule?
Four nitrogen bases: adenine, thymine, cytosine, and
guanine, Deoxyribose sugar, Phosphate group, Hydrogen
bonds
3. Which structures make up the DNA backbone?
Repeating deoxyribose sugars and phosphate groups
4. All living organisms contain hereditary material. What
components of hereditary material are the same for all
living organism? Differ? Adenine, Thymine, Guanine,
Cytosine. The sequence or order of the nitrogenous bases.
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Station 5
Facts about DNA
1. Take the DNA Facts cards out of the plastic bag and
sort them according to whether the fact is correct or
not. Record the correct facts in the space below.
DNA Facts:
Found in all living organisms.
Composed of a double helix.
Contains four bases: adenine, guanine, thymine,
and cytosine.
The amount of adenine found in DNA is the same
as the amount of thymine.
Weak hydrogen bonds hold the DNA molecules
together.
Called the “blueprint of life.”
There are two types of pyrimidines in DNA,
thymine and cytosine.
Nucleotides are made up of sugar, phosphate, a
base, and a hydrogen bond.
Genes are pieces of DNA that pass traits to
offspring.
There are two types of purines in DNA, adenine
and guanine.
DNA is deoxyribonucleic acid.
Review
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Cell Cycle, Mitosis, Meiosis, Meiosis, & DNA Structure/Replication
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Station 6
DNA Replication Videos
1. Use your mobile leaning device (MLD) to scan the QR
codes. Watch the videos about DNA Replication and
answer the following questions.
a. When would a cell need to undergo DNA replication
and make a copy of its own DNA?
DNA replication happens prior to cell division.
b. When DNA replication begins, the original strands
separate between the base pairs by an enzyme
called
helicase
. The location where this
occurs along the original strand is between the
nitrogenous bases
.
c. New nucleotides are added to the original parent
strand by an enzyme called DNA polymerase.
a. If the original strand contains adenine (A)
what base pair with be added to compliment
it on the new strand?
Thymine
b. If the original strand contains guanine (G)
what base pair will be added to compliment
it on the new strand?
Cytosine
d. If DNA replication is occurring in a eukaryotic cell,
in which organelle could it be observed happening?
The nucleus
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Biology
Cell Cycle, Mitosis, Meiosis, Meiosis, & DNA Structure/Replication
STAAR-EOC
e. Explain why this statement is true: The two strands
after replication are identical to the original strand
prior to replication.
During the process of DNA replication the parental
double helix is separated and used as a template.
Two strands are copied according to the
complementary base pairing rules of DNA. This
procedure produces two identical DNA molecules
which are referred to as daughter cells.
Review
35
Genetics
STAAR-EOC
Activity E
Protein Synthesis &
Point Mutations
Station 1
Transcription
1. Locate the transcription information page, identify the
base-pairing rules for transcription and complete the
following chart. This chart will serve as a tool to help you
synthesize the mRNA molecule.
DNA
nucleotide
G
C
T
A
Complementary
nucleotide in RNA
C
G
A
U
2. Notice that the process of transcription is similar to the
process of DNA replication. List some similarities
between transcription and DNA replication?
In both cases:
An enzyme will copy one strand of DNA to make a new
strand.
The new strand can be made because DNA will base pair
with a complimentary base. Thus, the new chain is
generated using the old/DNA strain as a template.
Additional answer will exist
3. There are also a few important differences between
DNA replication and transcription. Fill in the blanks in
the following table to summarize these differences.
36
Biology
Genetics
Review
STAAR-EOC
DNA
replication
Transcription
The whole
chromosome is
replicated.
___A single gene______is
transcribed.
DNA is doublestranded. DNA
remains in
nucleus.
mRNA is made.
mRNA is __single ___ -stranded, will
eventually leave nucleus for
translation.
DNA polymerase
is the enzyme
which carries
out DNA
replication.
_RNA_ polymerase is the enzyme
which carries out transcription.
T = thymine is
used in DNA,
so A pairs with
T in DNA.
T = thymine is replaced
by _U_ = uracil in RNA,
so A in DNA pairs with _U_ in mRNA.
37
Genetics
STAAR-EOC
Station 2
Translation
1. Use the mRNA codon chart shown in the translation
information page to help complete the following chart.
Amino acid threonine has been complete for you as an
example.
Amino acid
mRNA
codon
Anti-codon in tRNA
molecule
that carries this
amino acid
Threonine (Thr)
Histidine (His)
Proline (Pro)
Leucine (Leu)
Glutamic acid (Glu)
ACU
CAU
CCU
CUG
GAG
UGA
GUA
GGA
GAC
CUC
Valine (Val)
GUG
CAC
2. tRNA’s bring amino acids to which organelle in a cell to
be synthesized into a protein? Ribosomes
3. Each codon “codes” for how many amino acids?
1 amino acid
4. How many codons are needed for 3 amino acids?
3 codons
5. True or False? The order of nitrogenous bases in DNA
determines the order of amino acids in proteins?
True
6. Explain why it makes sense to use the word translation
to describe protein synthesis.
During translation, the genetic code, carried by mRNA,
is decoded/translated to produce a specific sequence
of amino acids in a poly peptide chain.
7. Explain why it would not make sense to use the word
translation to describe mRNA synthesis.
During transcription, the genetic code is
processed/transcribed into a copy of genetic
information. This genetic information is stored in DNA
and a complimentary strand, mRNA, is created to
move this information into the cytoplasm.
38
Biology
Genetics
STAAR-EOC
Station 3
Point Mutations
1.
G
U
Locate the colored plastic cubes and colored
cube key at this station. Arrange the cubes in the
order shown in the picture below. These cubes
are arranged in groups of three, and each group
represents a codon.
G
A
G
G
C A U
C C G
A C U
C C U
G A
These types of mutations are called point mutations.
What effect do the point mutations have on the protein
strands coded in the sequence above? Be sure to
translate both mRNA molecules when answering.
G
2.
C
A
U
C
U
G
A
C
U
C
C
U
G
Some genetic mutations are caused by changes
in the bases of some codons. Examine the
sequence of codon’s below.
In the sequence below, uracil (U) has been
replaced with cytosine (C) in one of the codons.
G
U
Valine
Histindine
Leucine
Threonine
Proline
Glutamate
Original Sequence Amino Acid Strand
Valine
Histindine
Proline
Threonine
Proline
Glutamate
Mutated Sequence Amino Acid Strand
The protein strand has not been assembled correctly. This
mistake is only found in one amino acid. Leucine should have
been added into the chain, instead proline was added.
Review
39
Genetics
STAAR-EOC
3. Locate the sequence of codons assembled for Question 1.
Find the codon CUG. Add one additional uracil base to the
beginning of the CUG codon. It now reads UCU—the G
base shifts to the next codon, causing all the subsequent
codons to shift one of their bases to the next codon as
well. This type of mutation is called a frame-shift
mutation.
Rearrange all the plastic codons to reflect the frame-shift
mutation described—that is, after you’ve added a uracil
base to the beginning of the CUG codon, shift the last
base of each remaining codon to the next codon, all the
way to the end of the strand.
4. Write the new codon arrangement below and identify the
amino acids using the mRNA Genetic Code Chart.
Insertion of new base
GUG
CAU
UCU
GAC
UCC
UGA
G
5. What is the significance of this frame-shift mutation for
the structure of the protein?
The point mutation shifted the remaining nucleotide bases
which will cause different amino acids to be coded for.
This mutation will result in an amino acid which differs
greatly from the expected result.
6. What other mutations could cause a frame-shift?
Deletion, Duplication, Translocation, Insertion, etc.
40
Biology
Genetics
STAAR-EOC
7. Sickle cell anemia results from a mutation at the Number
6 codon that causes the beta globin gene to be misread,
which results in the production of abnormal hemoglobin.
Use the information on the genetic mutation cards and the
mRNA genetic codes chart to fill in the protein strand with
the mutation that could cause this kind of anemia.
CAT
GUA
What type of point mutation is this? (multiple choice)
A. Substitution
B. Deletion
C. Insertion
D. Duplication
E. Repeating
8. Review the Genetic Mutation cards. Which mutations are
considered beneficial to humans? Why these mutations
considered beneficial?
The orchid plant mutation (extra sets of chromosomes) is
considered beneficial because it results in larger, more
showy, and, in some cases more fragrant flowers.
The strawberry mutation, which produces extra sets of
chromosomes, is considered beneficial because it results
in larger fruit, which is more desirable to consumers.
Review
41
Genetics
STAAR-EOC
Station 4: Protein Synthesis Simulation
1. Locate the Nucleus and Ribosome mats and the
Protein Synthesis Cards.
2. You will begin in the nucleus of the cell (Nucleus
Mat). Find the strip of DNA that starts with the
gene for hemoglobin. Place this down on the mat
in the appropriate location.
3. Find the correct RNA codons that complement the
strand of DNA before leaving the nucleus as
mRNA.
4. What was this process called?
Transcription
5. Find the corresponding tRNA anticodons and lay
them on the mat in the correct boxes.
6. Lastly, you will need to use your Codon Chart and
determine the order of the amino acids that the
tRNA will bring in as it matches up with each of
the mRNA codons.
*REMEMBER – YOU WILL LOOK AT THE CODONS
(mRNA) TO DETERMINE THE RIGHT AMINO ACIDS.
7. Write your amino acid sequence:
_Valine__-Histindine__- Leucine__
8. When this chain of amino acids is complete, what
will your product be? __Protein__
9. What was this second part of the process called?
Translation
42
Biology
Genetics
STAAR-EOC
Gene Expression:
All cells contain a set of genes, which can be thought of
as a set of instructions for making each of a very large
number of proteins. The creation of a protein from
its gene is called gene expression. However, for a
given cell not all of these instructions are actually used,
and among those that are, some are used more than
others or only under certain circumstances. Controlling
gene expression is critical to a cell because it allows it to
avoid wasting energy and raw materials in the synthesis
of proteins it does not need. Thus, it allows a cell to be
a more streamlined and versatile entity that can
respond to changing conditions by adjusting its
physiology.
Why don’t cells express all their genes at one time?
It would be an excessive waste of energy and materials
Adrenaline is a chemical secreted by the adrenal glands.
Describe a moment when the genes for adrenaline
would be “expressed”.
During and emergency situation.
Gene expression is a regulated process. What would be
a disadvantage of secreting adrenaline all the time?
A waste of energy and materials during a time when it is
not needed. Could cause more damage to body than
actual help.
Read more: http://www.biologyreference.com/CeCo/Control-of-Gene-Expression.html#ixzz3VQMjsVkS
Review
43
Genetics
STAAR-EOC
Post Assessment:
Answer the following questions over Protein Synthesis.
Correct Answer: C, Messenger RNA
Correct Answer: B, The offspring of the organism
44
Biology
Genetics
STAAR-EOC
Correct Answer: A, GTT produces Glutamine
Review
45
Genetics
STAAR-EOC
Activity F
Genetics
Vocabulary Word
Genetics
Definition
Example
Study of
how traits
are passed
from parent
to offspring
Gene
Is a segment
of DNA that
determines
a trait.
Alleles
46
Are different
genes
(possibilities
) for the
same trait
Tt = Brown eyes
TT = Brown eyes
Tt = Blue eyes
Biology
Genetics
STAAR-EOC
Homologous Pairs
matching
genes – one
from female
parent and
one from
male parent
that code for
a particular
trait.
Dominant Gene
Gene that
prevents the
other gene
from
“showing” –
represented
by a capital
letter
“T”
Recessive Gene
Gene that
does NOT
“show” even
though it is
present –
represented
by a
lowercase
“t”
letter
Review
47
Genetics
STAAR-EOC
Homozygous/Purebre
d
Both genes
of a pair are
the same
Heterozygous/Hybrid
One
dominant
and one
recessive
gene
Genotype
Combination
of genes an
organism
has (actual
gene
makeup)
Ex: TT, Tt,
tt
Phenotype
Physical
appearance
resulting
from gene
make-up
Ex: Blonde Hair,
Brown eyes, Freckles,
Curly hair, Fur color
48
TT or
tt
Tt
Biology
Genetics
STAAR-EOC
PRACTICE PROBLEMS:
MONOHYBRID CROSSES
In pea plants, tall (T) is dominant to short (t).
1. What is the genotype for a homozygous tall plant?___TT_____
2. What is the genotype for a heterozygous tall plant?__Tt_____
3. What is the genotype for a short plant?_tt_______
4. What is the genotype for a hybrid plant? __Tt______
In guinea pigs black coat (B) is dominant while white coat (b) is
recessive. Use a Punnett square to show all possible offspring. Give
the genotypic and phenotypic ratios for problem 5.
5. Cross a homozygous black with a white parent.
BB x bb
Genotype: 4 Bb
Phenotype: 4 Black
Review
49
Genetics
STAAR-EOC
DIHYBRID CROSSES
In guinea pigs, rough coat (R) is dominant over smooth (r) and Black
(B) is dominant over white (b). Give the genotypic and phenotypic
ratios for the below cross.
6. Cross a male guinea pig that is heterozygous for both traits with a
female white smooth coat.
Gametes
RrBb
rrbb
RB
rb
RrBb x rrbb
Rb
rB
rb
Genotype: 4 BbRr, 4 Bbrr, 4bbRr, 4 bbrr (1:1:1:1 ratio)
Phenotype: 1 Black/Rough, 1 Black/Smooth, 1 white/rough,
1 white/Smooth
INCOMPLETE DOMINANCE/CODOMINANCE
7. In four o’clock flowers, red (R) is incompletely dominant over white
(r) and the hybrid are pink flowered. For the following cross give
the genotypic and phenotypic ratios for the F1 generation.
a. Rr X RR
50
Biology
Genetics
STAAR-EOC
Genotype: 2 RR, 2 Rr
Phenotype: 2 Red, 2 Pink
SEX – LINKED TRAITS
8. A female homozygous for normal color vision (N) marries a colorblind (n) male. What are the possible genotypic and phenotypic
ratios of their offspring? Which offspring are carriers for
colorblindness?
Female XNXN x Male XnY
Genotype: 2 XNXn , 2 XNY
Phenotype: 2 Carrier, Normal Vision Females, 2 Normal Vision Males
PEDIGREES
•
Review
Draw a pedigree for the following couple. Dana is color blind;
her husband Jeff is not. They have two boys and two girls.
HINT: Colorblindness is a recessive sex-linked trait.
51
Genetics
STAAR-EOC
2 CARRIER
FEMALES
2 COLORBLIND MALES
MULTIPLE ALLELES
9. A man with type O blood marries a woman with type AB blood.
What will be the possible genotypes and phenotypes of their
children?
iO iO x IAIB
A = Dominant
B = Dominant
AB = Codominant
o= Recessive
Genotype: 2 IA iO , 2 IB iO
Phenotype: 2 A Blood, 2 B Blood
52
Biology
Genetics
STAAR-EOC
At times, mutations happen during the process of
meiosis. This can lead to significant changes in the
offspring of an organism. Below are some common
types of chromosome mutations. Determine how the
genes would be affected in each situation.
Deletion
ABC●EF
(Resulting Chromosome Structure)
Duplication
ABBC●DEF
(Resulting Chromosome Structure)
Inversion
AEC●DBF
(Resulting Chromosome Structure)
Translocation
ABC●IJKL
GH●DEF
(Resulting Chromosome Structure)
Review
53
Genetics
STAAR-EOC
1. Which of the following could only be a result of
nondisjunction during meiosis of sperm formation and
not egg formation? (multiple choice)

54
A.
XYY
B.
XXX
C.
XXY
D.
XO
Justify your answer:
A double Y is the only possibility
because egg formations don’t
include Y chromosomes. Being
doubled concludes nondisjunction.
Which of the following types of Gene/Point Mutations
demonstrates an additional gene added to the original
chromosome? ___Insertion___
Biology
Genetics
STAAR-EOC

Which of the following types of Gene/Point Mutations
demonstrates the loss of a gene from the original
chromosome? ___Deletion________

Examine the karyotype on the right, which chromosomal
abnormality is present? __Trisomy 21 (Downs Syndrome
caused by nondisjunction (failure of chromosomes to
separate).

GENE-POINT or CHROMOSOMAL are less drastic and
more common of the two mutations.
Post Assessment:
Answer the following questions on genetic crosses.
Correct Answer: A, 25%
Review
55
Genetics
STAAR-EOC
Correct Answer: F, 0 BB: 2:Bb 2: bb
56
Biology
Plants, Nitrogen & Carbon Cycles, & Relationship of Organisms
Review
STAAR-EOC
57
Plants, Nitrogen & Carbon Cycles, & Relationship of Organisms
STAAR-EOC
Activity G
Taxonomy & Stability of Environment
Station 1
Taxonomy
1. Locate the envelope containing the Domain and
Kingdom cards. Make sure you have plenty of space on
your table, then place the domain cards in a row as
shown, with Archaea on the left.
2. Place the kingdom cards beneath the domains to which
they belong. Use the Domain–Kingdom Arrows to
indicate precisely the domain to which each kingdom
belongs.
3. Now, select a Kingdom Characteristics card from the
envelope and place it under the appropriate kingdom
(see below). Continue until all of the cards are correctly
placed. Leave these cards in place.
58
Biology
Plants, Nitrogen & Carbon Cycles, & Relationship of Organisms
STAAR-EOC
4. The Kingdom Characteristics cards are shown below
in random order. Referring to your work, write the
name of the kingdom that best fits the characteristics
listed in the space at the top of each column.
Animalia
Eubacteria
Plantae
Archaebacteria
Fungi
Protista
5. Locate the Organism cards envelope. Examine the
pictures of the different organisms and discuss their
characteristics with your team. Determine the
kingdom to which each organism belongs and place
each organism picture under the appropriate
kingdom card. (You may need to take up the
Kingdom Characteristics cards to make room.)
Review
59
Plants, Nitrogen & Carbon Cycles, & Relationship of Organisms
STAAR-EOC
6. Fill in the six kingdoms in the top row of the table.
Then, referring to your work, list the names of the
organisms that belong to each kingdom in the columns
below.
Organisms in the Six Kingdoms
Archaebacteria
 Methanobacterium
bacteria
 Halophile bacteria
 Thermophile
bacteria
Fungi
 Bread mold
 Penicillum mold
 Bracket fungi
 Mushrooms
Eubacteria
 Cocci bacteria
 Bacillus bacteria
 Spirullium bacteria
Plantae
 Grasses
 Equisetum (horsetail)
 Oak tree
 Venus fly trap
 Fern plants
 Moss
 Spruce tree
Protista
 Ameba
 Paramecium
 Spirogyra green algae
 Saragassum brown
algae
 Red marine algae
 Diatoms
Animalia
 Earthworm
 Jellyfish
 Starfish
 Crayfish
 Clam
 Diamond back
rattlesnake
 Squirrel
 Bluejay
 Bull frog
 Catfish
 Swallowtail butterfly
7. Select an organism from one of the kingdoms and
explain why you placed it in that kingdom.
Organism___________
Kingdom________________
Justify…
60
Biology
Plants, Nitrogen & Carbon Cycles, & Relationship of Organisms
STAAR-EOC
Station 2
Hierarchical Classification System, Cladograms &
Dichotomous Key
1. Locate the Taxonomy cards and arrange them on the
Hierarchical Classification System sheet. The card that
represents the largest number of organisms should be
placed at the top of the column. Record your results
below.
Domain
Kingdom
Phylum
Class
Order
Family
Genus
species
2. Why is it important to scientists to have a
standardized classification system?
Having a standardized classification system means
that all scientist follow the same system. This
brings clarity to the study of organisms by
ensuring that scientists in different parts of the
world don’t end up giving different names to the
same organisms.
Review
61
Plants, Nitrogen & Carbon Cycles, & Relationship of Organisms
STAAR-EOC
3. Use the chart below to answer the following questions.
Organism
House cat
Red fox
Dog
Wolf
Gopher
Fly
Kingdom
Animalia
Animalia
Animalia
Animalia
Animalia
Animalia
Phylum
Chordata
Chordata
Chordata
Chordata
Chordata
Arthropoda
Class
Mammalia
Mammalia
Mammalia
Mammalia
Mammalia
Insecta
Order
Carnivora
Carnivora
Carnivora
Carnivora
Rodentia
Diptera
Family
Felidae
Canidae
Canidae
Canidae
Geomyidae
Muscidae
Genus
Felis
Vulpes
Canis
Canis
Thomomys
Musca
Species
domesticus
fulva
familiaris
lupus
bottae
domestica
a. How does the table below indicate that a dog is
more closely related to a red fox than house cat?
The table displays the entire hierarchical
classification for each organism. The more an
organism matches each level of the classification
the more closely related they are.
b. At what taxonomic level does the relationship
between gophers and house cats diverge?
Their relationship diverges at the order level.
c. What two animals are most closely related?
The dog and wolf
d. What type of animal is a Vulpes fulva? How do you
know?
Red fox
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Biology
Plants, Nitrogen & Carbon Cycles, & Relationship of Organisms
STAAR-EOC
4. Refer to the Cladogram below and answer the
following questions.


a. Identify and label with a
which dinosaur has
the most recent common ancestor of the robin
and Archaeopteryx.
b. Which traits are shared by the Archaeopteryx
and robins?
Light bones, 3-toed foot; wishbone, down
feathers, feathers with shaft, veins, and barbs
5. What factors do scientists use to construct a
cladogram?
-Shared derived characteristics
-DNA sequences
-Fossils
-Anatomical structures
-Embryology
Review
63
Plants, Nitrogen & Carbon Cycles, & Relationship of Organisms
STAAR-EOC
6. A dichotomous key is a tool used to identify
organisms. It consists of pairs, or couplets, of
descriptions of organism. By choosing the
description in each pair that matches the
description of an unknown organism, you can
identify the organism.
Locate the Cockroach Classification sheet. Utilize
the dichotomous key to identify each cockroach.
B
German Cockroach
____________
1
64
C
E
Australian Cockroach Cuban Cockroach
_____________
2
____________
3
Biology
Plants, Nitrogen & Carbon Cycles, & Relationship of Organisms
STAAR-EOC
Station 3
Stability of Environment
1. Using the Desert Food Web (pictured below) for
guidance, create a food web with the animal
cards provided. Write it down in the blank box on
the next page:
Review
65
Plants, Nitrogen & Carbon Cycles, & Relationship of Organisms
66
STAAR-EOC
Biology
Plants, Nitrogen & Carbon Cycles, & Relationship of Organisms
STAAR-EOC
Post Assessment: Answer the following
questions over Taxonomy, Ecological
Relationships, and Classification.
Correct Answer: G
Correct Answer: G, Mutualism
Review
67
Plants, Nitrogen & Carbon Cycles, & Relationship of Organisms
STAAR-EOC
Correct Answer: J, Arthropods of the same
species
Correct Answer: D, Platyhelminthes
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Biology
Plants, Nitrogen & Carbon Cycles, & Relationship of Organisms
STAAR-EOC
Correct Answer: G, Decomposers
Correct Answer: C, Have a common understanding
in the classification of organisms.
Review
69
Plants, Nitrogen & Carbon Cycles, & Relationship of Organisms
STAAR-EOC
Correct Answer: H
70
Biology
Additional Notes
STAAR-EOC
I need to remember…
Biomolecules:
 Sugars, the smallest carbohydrates, serve as
fuel.
 Lipids store large amounts of energy.
 A protein’s function depends on its unique
sequence of amino acids.
 Nucleic acids store and transmit hereditary
information.
 Organic molecules contain carbon-hydrogen
bonds and are produced by organisms.
Prokaryotic & Eukaryotic:
 Prokaryotic cells do not have a true nucleus.
 In eukaryotic cells, the DNA is surrounded by a
membrane.
 Both types of cells have ribosomes.
 Some eukaryotic cells and all prokaryotic cells are
surrounded by a cell wall.
 Eukaryotic cells have organelles surrounded by
membranes.
 Prokaryotic cells can reproduce only asexually, by
fission or budding.
 Eukaryotic cells reproduce asexually and sexually.
Cellular Processes/Energy:
 The products and reactants for photosynthesis
are reverse in cellular respiration: The reactants
of photosynthesis are carbon dioxide and water,
which are the products of cellular respiration. The
reactants of cellular respiration are oxygen and
sugar, which are the products of photosynthesis.
 Cellular respiration occurs in plants and anima
cells.
 Plants use sunlight during photosynthesis to
convert energy from the sun in order to
manufacture sugar and the chemical energy ATP
and to release oxygen.
Review
71
Additional Notes
STAAR-EOC
I need to remember…
Cellular Processes/Energy Cont.:
 ATP is used by plant and animals cells.
 As cellular respiration occurs, ATP is converted to
ADP.
 When plants are placed in darkness, cellular
respiration continues, using ATP to convert sugar
into ADP and releasing carbon dioxide.
Photosynthesis stops in the absence of light
energy.
 The chemical formula for photosynthesis is:
6H2O + 6CO2  C6H12O6 + 6O2 + ATP
 The chemical formula for cellular respiration is:
C6H12O6 + 6O2  6H2O + 6CO2 + ADP
Transport of Molecules & Homeostasis:
 Osmosis is the movement of water molecules
across a semipermeable membrane.
 Sometimes the movement of molecules across a
semipermeable membrane requires energy.
 When the number of molecules inside a cell is
equal to the number of molecules on the outside
of the cell, homeostasis has been reached – the
cell is in equilibrium.
Viruses:
 Viruses lack the cell structures necessary for
reproduction.
 Viruses are considered nonliving.
 Viruses can replicate by two methods – lytic
infection and lysogenic infection.
 Lysogenic infections occur when the nuclear
material of the virus combines with the DNA of a
cell before replication of the virus begins.
 Viruses and cells have one structure in common,
nucleic acids.
 HIV is a virus that infects and destroys immune
system cells.
72
Biology
Additional Notes
STAAR-EOC
6H2IOneed
+ 6CO
26H2O + 6CO2
to remember…
Cell Cycle:
 The cell cycle is a continuous process of cell
growth and reproduction.
 The cell cycle goes through interphase, the
longest phase, before undergoing mitosis and
cytokinesis.
 A cancer cell can develop during any part of
interphase. A cancer cell is a cell that goes
through the cell cycle continuously, never
stopping in G0. These cells consume the body’s
resources.
 Growth results from mitosis.
 There are checkpoints during the cell cycle to
help cells divide correctly.
DNA:
 DNA molecules contain four nitrogenous bases:
adenine, guanine, cytosine and thymine.
 Two bases – adenine and guanine – are called
purines.
 Two bases – thymine and cytosine – are called
pyrimidines.
 Genes are pieces of DNA that pass traits to
offspring.
 Nucleotides are made up of a sugar, a phosphate
group, a base, and hydrogen bongs.
 The amounts of adenine and thymine found in
DNA are equal.
 DNA molecules are made up of a double helix
containing two strands.
 Weak hydrogen bonds hold the DNA molecule
together.
 DNA is found in all living organisms.
 DNA stands for deoxyribonucleic acid.
 DNA us referrd to as the “blueprint of life”
because it contains all the information in a living
organism.
Review
73
Additional Notes
STAAR-EOC
I need to remember…
Protein Synthesis:
 RNA stands for ribonucleic acid.
 RNA is single stranded.
 RNA molecules contain four nucleotide bases:
adenine, guanine, cytosine and uracil (replaces
thymine)
 Transcription is the process of creating an mRNA
molecule and this takes place inside the nucleus.
 Translation is the process of decoding mRNA
using tRNA triplets/codons. These codons carry a
specific amino acid they connect and create a
protein.
Changes in the Genetic Code:
 Mutations are changes in DNA that can be
inherited.
 Certain codons are responsible for starting the
production of a protein, and other codons stop
the process.
 Mutations occur when bases are added or deleted
and when segments of DNA are missing.
 Not all mutations are harmful – some are very
beneficial.
Genetic Variations (I need to be able to):
 Analyze and make inferences about dominant
and recessive traits.
 Interpret and make predictions about genotypes
and phenotypes.
 Determine and interpret phenotypic ratios.
 Understand the difference between Mendelian
and non-Mendelian traits.
 Use Punnett squares and other models to predict
the results of genetic crosses involving X-linked
traits.
 Interpret results and make predictions from
monohybrid and dihybrid crosses.
 Evaluate the limitations of biological models.
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Biology
Additional Notes
STAAR-EOC
I need to remember…
Evidence of Ancestry (Evolution):
 DNA sequences are used to determine how
closely related organisms are to one another.
 Examining fossil remains enables scientists to
understand how modern organisms developed
over time.
Natural Selection:
 No organism or population of organisms is
perfectly adapted to its ecosystem.
 Natural selection does not produce perfection in
the organisms that are adapted to an ecosystem.
 Adaptations are due to genes that are heritable.
 Natural selection occurs as the result of three
conditions: variations in characteristics in a
population, heritable traits, and differences in
fitness among organisms within a species.
 Survival of the fittest does not refer to how
physically fit or strong an orgasm is; rather, it
refers to an organism’s ability to reproduce and
pass on its traits to the next generation.
 Natural selection does not act on an individual to
make it better adapted to its environment.
 There are biological and physical influences that
determine the survival and success of organisms.
 There are three types of evolution that occur as a
result of natural selection – divergent evolution,
convergent evolution, and coevolution.
Taxonomy:
 Scientists use internal and external
characteristics to classify organisms into similar
groups.
 Within the hierarchical classification system, the
domain is the group that includes the greatest
number of organisms and exhibits the greatest
diversity of organisms.
 The species is the group that includes the fewest
number of organisms and exhibits the least
diversity of organisms.
Review
75
Additional Notes
STAAR-EOC
I need to remember…
Taxonomy Cont.:
 Taxonomy is a branching classification system
that provides a standardized method for grouping
organisms.
Trophic Level Interactions:
 Organisms in an ecosystem interact in ways that
can be shown in food chains and food webs.
 Ecological pyramids are used to illustrate how
organisms in an ecosystem transfer matter and
energy from one trophic level to another.
 Approximately 10 % of the available energy in a
trophic level is passed on to the next trophic
level. The remaining energy, approximately 90%,
is used for metabolic functions or dissipated as
heat.
 Sunlight – radiant energy – is transferred to
plants through photosynthesis. Organisms that
feed on plants are able to use about 10% of the
energy that was available to the plants. The
transfer and dissipation of energy continue from
one trophic level to the next.
Ecological Succession:
 Species living in an ecosystem gradually change
over time, as do the physical and chemical
environments within that ecosystem.
 Succession takes place because organisms
interact with one another in an ecosystem.
 Left undisturbed, succession follows predictable
stages: primary, secondary and climax
communities.
 Autotrophs are the first pioneer species to
inhabit an ecosystem in the primary stage; they
create conditions that may be favorable to other
autotrophs.
 Heterotrophs follow autotrophs in the stages of
succession – first herbivore heterotrophs and
then carnivores and omnivores.
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Biology
Additional Notes
STAAR-EOC
I need to remember…
Ecological Succession Cont.:
 An ecosystem reaches stability when it becomes
a climax community. In this stage it is stable,
mature, self-sustaining, and has reached an
ecological equilibrium.
Changes in Ecological Stability:
 Mutualism, commensalism, parasitism, and
predator/prey relationships are all types of
interactions that occur among organisms in an
ecosystem.
 The stability of an ecosystem can be affected by
a natural disaster.
 Natural disasters such as hurricanes, droughts,
floods, and so on can alter the stability of an
ecosystem. These disasters can cause some
organisms to diminish in number or become
extinct so that their niche in an ecosystem is
altered. It can take years for an ecosystem to
recover from a natural disaster and regain
stability.
Relationship of Organisms:
 Organisms in an ecosystem exhibit different
types of relationships as they interact.
 Some ways organisms interact is by competing
for food and other resources.
 Relationships that may be found in an ecosystem
include parasitism, commensalism, mutualism,
and predator/prey.
Plant Systems:
 Plants, like animals, are composed of different
systems that interact to benefit the plant.
 Some systems enable the plant to respond to
stimuli it receives from its environment, such as
touch, light, and gravity.
 One system cannot survive without interacting
and depending on other systems in the plant.
Review
77
Additional Notes
STAAR-EOC
I need to remember…
Plant Systems Cont.:
 Each system is composed of smaller systems; for
example, the transport system is composed of
xylem and phloem found in the leaves, stems,
and roots of plants.

The reproductive system reproduces either by
sexual or asexual means, depending on the plant.
Animal Systems:
 Systems do not stand alone; they must work with
other systems to enable the organism to function
properly.
 Each system has specific function that it must
perform, but each system is closely connected to
other systems in the body and works with them
to perform its functions.
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Biology
Credits
Charles A. Dana Center at The University of Texas at
Austin, STAAR Biology Assessments: Module 1
McGraw-Hill, http://tx-science.cinchlearning.com, CINCHScience for Texas
Serendip, http://serendip.brynmawr.edu/biology, Handson Activities for Teaching Biology to High School
Students
Windows to the Universe, National Earth Science Teachers
Association, http://windows2universe.org, Teacher
Resources