Mrs. Hochmuth
What Should I Bring Everyday?
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Fusion Workbook
Science Folder
Science Journal
Science Fair Materials
Pencil & Pens
Good Attitude!
What Will We Do Everyday?
• Make Observations
– Write in our Science Journals
• Preform Labs
– Launch Labs, Mini Labs and Unit Labs
• Gain Understanding
– Reading for information
– Creating lesson note outlines
– Define vocabulary terms
• Provide Evidence
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Active reading questions
Lesson review questions
Lesson quizzes
Module Quest
Where Can I Find Things In The
Classroom?
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Extra School Supplies
Homework Turn In Tray
Replacement Handouts
Absent Work
Graded Work
Goals For The Day
Class Announcements
Additional Resources
What Are The Classroom Rules?
• Respect yourself, others, and property.
• Stay in your seats.
• Be Safe.
• Follow ALL directions given by Mrs.
Hochmuth.
• Attempt All Tasks Before Asking For Help.
What Happens If I Forget To Follow
The Classroom Rules?
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1st Time: Verbal Warning
2nd Time: Lunch Detention
3rd Time: Call Home
4th Time: Office Referral
NOTE:
Any of the above steps may be skipped if
behavior is deemed severe by Mrs. Hochmuth.
How Are Grades Taken?
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Alternative Assessment & Quests = 30%
Quizzes & Labs = 20%
Homework = 15%
Projects = 20%
Vocabulary/Science Journal = 10%
Positive Performance Points= 5%
NOTE:
– NO Late Work Will Be Accepted (Late = 0 Pts.)
– 1 Daily Assignment will be dropped every quarter
th
7
Grade Positive Performance
Points
What are Positive Performance Points?
They are points earned daily for:
•Bringing ALL materials to class
•Displaying acceptable behavior in class; NO gum
•Participating and staying engaged in class
You will earn 2 points a day for a total of 10 points per week
These points will be 5% of your overall grade, per class
How Do I Care For The Animals In Our
Classroom? (Dead and/or Alive)
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Ask For Permission Before Handling Animals
Wash Your Hands Before Handling Animals
Handle Animals With Care And Respect
Never Let Animals Out Of Sight When Handling
Wash Your Hands After Handling Animals
How Do I Get Involved In My School?
• Sports
– Baseball
– Volleyball
Basketball
Softball
Track/Cross Country
Cheerleading/Poms
• Team Activities
– Math Counts
– Chorus
Band/ Orchestra
Scholastic Bowl
Speech
Intramurals
• Clubs
– Art Club
Robotics
Chess
• Student Council- OH YES!
J.A.M
Spartan Learning
Community
• SLC is a time for working on AR and AM.
• No Talking Or Working On Homework Is Allowed.
• Bring Only Your READING BOOK to class on AR days. Your
AM folder will be in your SLC class for AM days.
• You may scan your AM exercises, practices, and tests in my
classroom. I can also print off any assignments you need
printed for AM.
• The Library may be visited by one student at a time. You
must sign out with your SLC teacher.
• Use 7th Grade House computers to take AR reading tests.
• Fill in any logs or questionnaires when you have completed
an AR book.
What Are Alternative Assessments
• An Alternative Assessment is
any means other than a
paper/pencil test to evaluate
understanding.
• Alternative Assessments may include
one or more of the following:
– Brochure/ Pamphlet
– Diary/ Journal
– Song/ Rap
– Model /Diorama
– Quiz Board
Cartoon/ Comic
News Report
Play/ Skit
WebQuest
Poster/ Power Point
Assessment Menu
• Choose 4 activities to complete per unit.
• Each activity will be 25 points each. These activity
assessments will take the place of a unit test.
• Once you have completed an activity, you CAN
NOT pick that activity again this school year.
• There are 6 units that will be introduced over the
school year. You will have a total of 24 activities
completed by the end of the school year.
• Do not spend a lot of money on these activities.
Use the materials you have around the house. I
have basic materials you can use or have here in
the classroom. I suggest spending no more than a
dollar or two on any activity.
Life Science Unit #1
The Scientific Method
How can science provide answers to your
questions about the world around you?
Science Journal #1: Vacuuming Coral?
No, these two divers are collecting data about corals
in waters near Sulawesi, Indonesia. They are
marine biologists, scientists who study living things
in oceans and other saltwater environments.
1. What info about
corals are these
scientists collecting?
2. What questions do
they hope to
answer?
Lesson #1: Understanding Science
• What is Science?
– The investigation and exploration of natural
events and of the new information that results
from those investigations.
• What behaviors do
scientist use in problem
solving?
– Reasoning,
– Creativity,
– Skepticism
Lesson #1: Understanding Science
• What are the branches of Science?
– Life Science
• The study of all living things
– Earth Science
• The study of Earth including its landforms,
rocks, soil and forces that shape Earth’s surface.
– Physical Science
• The study of chemistry and physics
Lesson #1: Understanding Science
• What is Scientific Inquiry?
– Observation: Using one or more of your senses to
gather information and take note of what occurs.
– Prediction: A statement of what will happen next
in a sequence of events.
– Hypothesis: A possible explanation
about an observation that can be
tested by scientific investigations.
– Inference: A logical explanation of an observation
that is drawn from prior knowledge or experience.
Lesson #1: Understanding Science
• How do you write a GOOD hypothesis?
– A GOOD hypothesis provides a possible
outcome and explanation for the outcome.
– Example:
• Some plants are growing
more quickly than other
plants because they are
receiving more water
than the others.
Lesson #1: Understanding Science
• What are some outcomes of Scientific Inquiry?
– Technology: The practical
of scientific knowledge,
industrial or commercial use.
(Computer controlled limbs)
use
especially for
– New Materials:
bone bioceramic mimics
natural bone structure
– Possible explanations:
Answers the Who? What? Where? Why? When?
Lesson #1: Understanding Science
• What is a scientific THEORY?
– An explanation of observations or events based on
knowledge gained from many observations and
investigations
– Example: The Cell Theory
• What is a scientific LAW?
– Describes a pattern or an
event in nature that is always true.
– Example: The Law Of Conservation Of Mass
Lesson #1: Understanding Science
• How are Scientific Theory and Scientific Law
Similar?
– Both will be rejected if new observations do not
support the theory or law.
– Both are based on repeated observations
• How are Scientific Theory and Scientific Law
Different?
– Scientific Theory explains
WHY something happens
– Scientific Law states that
something WILL happen.
Lesson #1: Understanding Science
• Where does reliable information come from?
– Media: News papers, television, radio and
magazines
– Important to ask..
• Is the information truthful?
• Is the information accurate?
• What is Critical Thinking?
– Comparing what you already
know with the information you
are given in order to decide
agree with it.
whether you
Lesson #1: Understanding Science
• What keeps a Scientific Investigations
accurate?
– Good investigations:
• Prevent BIAS- prejudice towards a specific outcome.
• Incorporate RANDOM SAMPLING- method of data
collection that involves studying small amounts of
something in order to learn about the larger whole.
• Utilize a BLIND STUDY- the investigator,
subject or both do not know which
item they are testing (placebo)
• Are REPEATABLE- results must
consistent among all trials
Lesson #1: Understanding Science
• How do scientists stay safe during
investigations?
– Wear appropriate safety equipment
– Recognize hazards and safety symbols
• How do ethics fit into scientific investigation?
– Ethics: rules of conduct or moral principles
– Living things should be treated with care
– Scientists should tell research participants about
potential risks and benefits of the research
– Anyone should be allowed to refuse participation
Science Journal #2:
Understanding Science
1. What is scientific inquiry?
2. What are the results of scientific
investigations?
3. How can a scientists minimize bias in a
scientific investigation?
Steps of the Scientific Method
• Ask Questions/State the Question
– Make observations, State the problem, Gather information,
• Research/Collect Information
– Provide background information about topic
• Hypothesis
– Predict the answer to your problem
• Experiment/Test your Hypothesis
– Design a test to confirm or disprove your hypothesis
• Analysis/Study your Data
– Graph results, classify information, make calculations
• Conclusion
– Communicate results
– You may have to retest
Lesson #2: Measurement
And Scientific Tools
• How do description and explanation relate to
observation?
– Descriptions are spoken or written summary of
observations.
– Explanations are interpretations of observations
• How do scientists use the International
System of Units?
– Scientists use the same internationally accepted
system for measurement called SI units to make
sure information can be shared and understood
internationally.
Lesson #2: Measurement
And Scientific Tools
• What measurement units do scientists use?
SI Basic Units Of Measure
Quantity Measured
Unit (Symbol)
Length
Meter (m)
Mass
Kilogram (kg)
Time
Electric Current
Temperature
Substance Amount
Light Intensity
Second (s)
Ampere (A)
Kelvin (K) or Celsius
(⁰C)
Mole (mol)
Candela (cd)
Lesson #2: Measurement
And Scientific Tools
• A prefix can be added to a base unit’s name to
indicate either a fraction or a multiple of that
Prefixes
base unit.
Prefix
Meaning
• Can be written
Mega- (M)
1,000,000 X
– 1Kilometer or 1 km
Kilo- (k)
1,000 X
Hecto- (h)
100 X
Deka- (da)
10 X
Deci- (d)
.1 X
Centi- (c)
.01 X
Milli- (m)
.001 X
Micro- (µ)
.0001 X
Lesson #2: Measurement
And Scientific Tools
• How are Accuracy and Precision related?
– Accuracy: Description of how close a
measurement is to an accepted true value.
– Precision: Description of how similar or close
measurements are to each other.
Lesson #2: Measurement
And Scientific Tools
• How are Accuracy and Precision
measurements limited?
– Tools used
• Measurements taken are only as accurate as
the tools used to gather them.
– Degree Of Rounding
• Significant digits in a
measurement include
all digits you know
for certain plus one estimated digit.
Lesson #2: Measurement
And Scientific Tools
• How do you know if a digit is Significant?
– All nonzero numbers are significant
– Zeros between nonzero digits are significant
– Final zeros used after the decimal point are
significant
– Zeros used solely for spacing the decimal point are
NOT significant. The zeros indicate only the
position of the decimal point.
Lesson #2: Measurement
And Scientific Tools
• What tools do ALL Scientists use?
– Science Journals: Record descriptions,
explanations, plans, and steps used in a scientific
inquiry.
– Balances: Used to measure Mass.
– Thermometer: Used to
measure temperature of
substances in ⁰C.
– Glassware: Used to hold,
pour, heat and measure liquids
Lesson #2: Measurement
And Scientific Tools
• What tools do ALL Scientists use?
– Compound Microscopes: Used to observe small
objects that you cannot observe with just your
eyes.
– Computers (hardware and software): Used to
compile, retrieve, and analyze date for reports.
Lesson #2: Measurement
And Scientific Tools
• What tools do Life Scientists use?
– Magnifying Lens: Hand-held lens
that magnifies, or enlarges, an
image of an object.
– Slide: Thin rectangular piece of glass
used to hold specimen for
microscope observation.
– Dissecting Tools: (scalpels &
scissors) used to examine tissues,
organs, or prepared organisms.
– Pipette: Small glass or plastic tube
used to draw up and transfer liquids.
Science Journal #3
Measurement and Scientific Tools
1. What is the difference
between accuracy and
precision?
2. Why should you use
significant digits?
3. What are some tools used by
life scientists?
Skill Practice#1: Follow a Procedure
Scientists often follow procedures
developed by other scientists to collect
data. A procedure is a step-by-step
explanation of how to accomplish a
task. The steps in a procedure tell you
what materials to use, how to use
them, and is what order to perform
specific tasks.
Skill Practice #1
Follow a Procedure
How can you build your own
scientific instrument?
Skill Practice#1: Follow a Procedure
Apply It:
Answer the following in your
science journal
1. Draw a diagram of your
set up also known as a
eudiometer. Label all the parts,
and describe their functions.
2. Describe a scenario in
which a life scientist would use
this instrument to measure
gases.
Lesson #3: Case Study
• What is biodiesel?
– Fuel made primarily from
living organisms such as
plants and plantlike
organisms. (algae)
• How are variables used in experiments?
– Variable: any factor in an experiment that can
have more than one value.
– Independent Variable: Factor you want to test.
– Dependent Variable: Observable outcome
dependent on Independent variable.
Lesson #3: Case Study
• What are some arguments
against using biodiesel as a
primary fuel source?
– Petroleum: historically
petroleum, a type of refined fossil
fuel, has cost less to produce.
– Sources of biodiesel: Some are
concerned that farmers will begin
growing crops for only fuel
production instead of food
production.
Lesson #3: Case Study
• How did scientists discover fuel
from plants?
• Aquatic Species Program (ASP) 1970s
– Original Focus: To use large and small plants to
remove excess Carbon Dioxide produced by coal
energy plants.
– Shifted Focus: Uncovered
that some small plants
called microalgae
produced large amounts
of oil after taking in
Carbon Dioxide.
Lesson #3: Case Study
• How did scientists turn their observation into
an experiment?
• Step #1- Create a tentative explanation that
can be tested by scientific investigation
– Hypothesis: Some microalgae species can be used
as a source of biodiesel fuel because the
microalgae produce a large amount of oil.
– Challenge: Finding the correct species of
microalgae, and growing conditions
to produce large amounts of oil.
Lesson #3: Case Study
• Step #2: Design an experiment and collect data
– ASP developed a rapid screening test to discover
which micro-algae species produced the most oil
– Independent Variable: Amount of nitrogen given
– Dependent Variable: Amount of oil produced
– Constants: growing conditions (temperature, light
water quality)
Lesson #3: Case Study
• Step #3: Observe impact of
independent variable
– Less Nitrogen resulted in…
smaller sized micro-algae organisms
less overall oil production
• Step #4: Revise Hypothesis and design 2nd test
- Hypothesis: If light is distributed more evenly then
more microalgae will grow and more oil will be
produced
Lesson #3: Case Study
• Step #5: Design 2nd controlled experiment to
test new hypothesis.
– Where could Microalgae be grown?
• Open Ponds
• Plastic Bags
• Glass Bioreactors
• What does it mean for an experiment to be
hypothesis driven?
- To develop research strategies or experiments
based on hypothesis.
Lesson #3: Case Study
• What is the difference between a prediction
and a hypothesis?
– Hypothesis: A possible explanation that can be
tested
– Prediction: A statement of what someone expects
to happen next in a sequence of events.
• If light is distributed more
evenly then more microalgae
will grow, and more oil will be
produced.
Lesson #3: Case Study
• Step #6: How to distribute light evenly?
– Bring light to Microalgae = Light rods
– Bring Microalgae to the light = Paddle Wheels
• Step #7: Analyze Results
– Results showed that microalgae would produce
more oil using light rods than just sun light
• Step #8: Draw conclusion
– Light rod system greatly increased
microalgae oil production
Lesson #3: Case Study
• Examine Benefits of Microalgae
– Removes carbon dioxide pollution
– Produces Carbohydrates,
and Lipids
• Used for Biodiesel,
Bioethanol, Human and
livestock food, and
pharmaceuticals and
cosmetics
– Adds Oxygen back to the
environment
• Is Microalgae The Future?
Science Journal #4
Case Study
1. How do independent and dependent
variables differ?
2. How is scientific inquiry used in real-life
scientific investigation?
Inquiry Lab #1: Design A Bioreactor
How can you design a bioreactor?
Inquiry Lab #1: Design A Bioreactor
• Analyze And Conclude
1. What conditions resulted
in the fastest growth of yeast?
2. Which of the two variables had a greater
influence on the growth of yeast? How
did you draw that conclusion?
3. Which scientific processes did you use in
your investigation of bioreactors?
Life Science Unit #2
Classifying and Exploring Life
What are living things, and how can they be
classified?
Science Journal #5:
Innovative Bird Nest Building?
At first glance, you might think a very strange
bird has made a unique nest on the ground, but
the object in the “nest” is no egg.
1. What do you think
the object is? Is it
alive?
1. What are living things,
and how can they
be classified?
Launch Lab #1: Is It Alive?
1. Place three pieces of pasta in the bottom of a
clear cup.
2. Add carbonated water to the cup until it is
2/3 full.
3. Observe the contents of
the cup for 5 minutes.
Record you observations
in your science journal.
Launch Lab #1: Is It Alive?
Think About This!
1. Think about living things.
How do you know they are alive?
2. Which characteristics of life do
you think you are observing in the cup?
3. Is the pasta alive? How do you know?
Lesson #1: Characteristics of Life
• What determines if something is living or
nonliving?
– Only things that have ALL the characteristics of life
are considered living, these living things are called
organisms.
• What are the 6 characteristics of life?
1. Organization
• Living things are made of cells- the smallest unit of life
• Living things that are made of only one cell are called
unicellular
• Living things that are made of more than one cell are
called multicellular.
Lesson #1: Characteristics of Life
• What are the 6 characteristics of life?
2. Growth and Development
• When organisms grow they increase in size
– Multicellular organisms grow as number of cells
increase
– Unicellular organisms grow as the cell size increases
• Changed that occur in
an organism during its
life time are called
development.
Lesson #1: Characteristics of Life
• What are the 6 characteristics of life?
3. Reproduction: The process by which one
organism makes one or more new organisms.
• Some organisms can reproduce by dividing and
becoming two new organisms
• Other organisms have
specialized cells for
reproduction that may or
may not require a mate
to reproduce.
Lesson #1: Characteristics of Life
• What are the 6 characteristics of life
– Response to Stimuli
• Internal Stimuli: Response to internal body
signals
– Example: if you feel hungry or thirsty you look for
food or water.
• External Stimuli:
Response to
environmental changes
– Example: Response to light
and temperature.
Lesson #1: Mini Lab
Did You Blink?
Like all living organisms, you
respond to changes, or stimuli, in
your environment. When you
react to a stimulus without
thinking, the response is known
as a reflex. Lets see what a reflex
is like.
Lesson #1 Mini Lab
Did You Blink?
1. Sit in a chair with your hands in you lap.
2. Put on your safety goggles
3. Have your lab partner gently toss a soft foam
ball at your face five times. Your partner will
warn you when he or she is going to toss the
ball. Record your responses in your science
journal.
4. Have your partner gently toss the ball at your
face five times without warning you. Record
your responses.
Lesson #1 Mini Lab
Did You Blink?
Analyze and Conclude
1. Compare your responses when you were
warned and when you were not warned.
2. Decide if any of your reactions were reflex
responses, and explain your answer.
3. Infer whey organisms have reflex responses
to some stimuli.
Lesson #1: Characteristics of Life
• What are the 6 characteristics of life?
– Homeostasis: Organisms ability to maintain steady
internal conditions when outside conditions
change.
• By maintaining certain conditions – Homeostasisensures that cells can function.
• If cells cannot function normally, then
the organisms might become sick
or even die.
Lesson #1: Characteristics of Life
• What are the 6 characteristics of life?
– Energy
• Cells continuously use energy to transport substances,
make new cells, and perform chemical reactions.
• For most organisms this energy comes to Earth from
the sun.
• Example:
– Plants get energy from the sun to
grow
– Deer get energy from the plants
they eat
– Mountain lions get energy from
the Deer they eat
Science Journal #6
Characteristics Of Life
1. What characteristics do all living
things share?
Lesson #2: Classifying Organisms
Launch Lab #2
How do you identify similar items?
Launch Lab #2
Do you separate your
candies by color before
you eat them? When
your family does laundry,
do you sort the clothes by
color first? Identifying
characteristics of items
can enable you to place
them into groups.
Launch Lab #2
1. Examine 12 leaves. Choose a characteristic that
you could use to separate the leaves into two
groups. Record the characteristic in your
Science Journal.
2. Place the leaves into two groups, A and B, using
the characteristic you chose in step #2
3. Choose another characteristic that you could
use to further divide group A. Record the
characteristic and divide the leaves
4. Repeat step #3 for group B.
Launch Lab #2
Think About This!
1. What types of
characteristics did other
groups in class choose to
separate the leaves?
2. Why would scientists need
rules for separating and
identifying items?
Lesson #2: Classifying Organisms
• How have organisms been classified in
the past?
– Ancient Greek philosopher Aristotle, one
of the first people to classify organisms,
placed all organisms into two groups:
Plants or Animals
– Aristotle classified animals based on shape
and size, the presence of “red blood,”
their environment
– Aristotle classified plants based on the
structure and size of the plant and
whether it was a tree, shrub or herb.
Lesson #2: Classifying Organisms
• How are organisms classified
today?
– In the 1700s Carolus Linnaeus,
a Swedish physician, placed all
organisms into two main
groups he called kingdoms.
– In 1969 American Biologist
Rober H. Whittaker prosed 5
kingdoms of classification:
Monera, Protista, Plantae,
Fungi and Animalia
Lesson #2: Classifying Organisms
• Today Scientists use a system of Domains
(3) and Kingdoms (6) to classify organism
• Domains: Bacteria, Archaea, and Eukarya
• Kingdoms: Bacteria, Archaea, Protista, Fungi,
Plantae, and Animalia
Lesson #2: Classifying Organisms
• How do Scientists use names to help classify
organisms?
– When Linnaeus grouped organisms into
kingdoms, he also developed a naming system
called binomial nomenclature.
– Binomial nomenclature gives each organism a
two word scientific name, a genus name and a
species name.
– Genus: group of similar species
– Species: group of organisms with similar traits and
are able to produce fertile offspring.
Lesson #2: Classifying Organisms
• Why Are Scientific Names important?
– Each species has its own scientific name
– Scientific names are the same worldwide
– Universal names make communication about
organisms more effective because everyone uses
the same name for the
same species.
Lesson #2: Classifying Organisms
• How do scientists use tools to classify
organisms?
– Dichotomous Key: Series of descriptions arranged
in pairs that leads the user to the identification of
an unknown organism.
– Cladograms: Branched diagram that shows the
relationship among organisms, including common
ancestors.
Lesson #2: Classifying Organisms
Mini Lab
How would you name an unknown organism?
Lesson #2: Classifying Organisms
Mini Lab
Assign scientific names to four unknown alien
organisms from a newly discovered planet.
1. Use the table to assign scientific names to
identify each alien.
2. Compare your names with your classmates.
Prefix
mon–
di–
rectanguli–
trianguli–
Meaning
Suffix
one
two
square
triangle
–antennius
–ocularus
–formus
–uris
Meaning
antenna
eye
shape
tail
Lesson #2: Classifying Organisms
Mini Lab
Analyze and Conclude
1. Explain why you chose the two-word names
for each organism.
2. Compare your names to those of a classmate.
Explain any differences.
3. Discuss how two-word scientific names help
scientists identify and organize living things.
Science Journal #7
Classifying organisms
1. What methods are used to classify living
things into groups?
2. Why does every species have a scientific
name?
Skill Practice #2: Classify
A dichotomous key is one of the tools scientists
use to identify an unknown organism and
classify it into a group. To use a dichotomous
key, a scientist examines specific characteristics
of the unknown organism and compares them
to characteristics of known organisms.
Skill Practice: Classify
How can you identify a beetle?
Skill Practice: Classify
Apply It!
1. Think about the choices in each step of the
dichotomous key. What conclusions can be
made if you arrive at a step and neither choice
seems correct?
2. Predict whether a dichotomous key will work if
you start at a location other than the first
description. Support your reasoning.
3. How did the dichotomous key help you classify
the unknown beetle?
Lesson #3: Exploring Life
Launch Lab #3
Can a water drop make
objects appear bigger or
smaller?
Launch Lab #3
For centuries, people have been looking for
ways to see objects in greater detail. How can
something as simple as a drop of water make
this possible?
Launch Lab #3
1. Lay a sheet of newspaper on your desk.
Examine a line of text, noting the size and
shape of each letter. Record your
observations in your Science Journal.
2. Add a large drop of water to the center of a
piece of clear plastic. Hold the plastic about
2 cm above the same line of text.
3. Look through the water at the line of text you
viewed in step 2. Record you observations.
Launch Lab #3
Think About This!
1. Describe how the newsprint
appeared though the drip of
water.
2. How might microscopes
change your ideas about
living things?
Lesson #3: Exploring Life
• How have microscopes changed the world?
– The invention of the microscope enabled people
to see details of living things that they could not
see with the unaided eye.
– The microscope also enabled people
to make many discoveries about
living things.
Lesson #3: Exploring Life
• What were the first microscope like?
– In the late 1600s Anton van Leeuwenhoek, a
Dutch merchant, Made one of the first
microscopes.
– The microscope had one lens and could
magnify an image about 270 times its
original size.
– Leeuwenhoek used his microscope to
observe pond water and insects.
– In the early 1700s Robert Hooke used a
microscope to observe cells proving
that all living things are made of cells.
Lesson #3: Exploring Life
• What characteristics do all microscopes
share?
– All microscopes magnify objects
– All microscopes improve the resolution of an
object (how clearly details can be seen)
• How many different types of microscopes are
there?
– Light microscopes
– Electron microscopes
Lesson #3: Exploring Life
• What are Light Microscopes?
– Light microscopes use light and lenses to
enlarge an image of an object.
– Compound light microscopes use more
than one lens to magnify an object.
• Magnifies first by the objective lens then by the
ocular lens
• Total magnification is equal to the
magnification of the objective lens multiplied
by the magnification of the ocular lens.
Lesson #3: Exploring Life
Practice!
1. What is the
magnification of a
compound microscope
with a 10X ocular lens
and a 4X objective lens?
Lesson #3: Exploring Life
• What are light microscopes?
– Light microscopes can enlarge up to 1,500 times
– Resolution is about 0.2µm (you can clearly see
points on an object that are at least 0.2µm apart)
– Simple Light Microscopes use light and one lens
– Compound Light Microscopes use light and more
than one lens (ocular and objective lenses)
– Can use to observe objects directly under
microscopes as well as those mounted on slides.
Lesson #3: Exploring Life
• What are Electron Microscopes?
– Electron microscopes use a magnetic field
to focus a beam of electrons through an
object or onto an object or onto an objects
surface.
– Electron microscopes can magnify up to
100,000 times or more
– Resolution can be as small as 0.2
nanometers (1,000 times greater than a
light microscope)
Lesson #3: Exploring Life
• What are Electron Microscopes?
– Transmission Electron Microscopes: used to study
very small nonliving things sliced thin and
mounted in plastic.
– Scanning Electron Microscopes: used to study the
surface of objects by bouncing
electrons to produce a 3
dimensional image.
Lesson #3: Exploring Life
• What are some uses for microscopes?
– Healthcare
• Used by doctors during surgeries such as eye and brain
surgery.
• Used by lab technicians to analyze body fluids and to
determine if body tissues are healthy or diseased.
– Other:
• Used by forensic scientists to study evidence from
crime scenes
• Used by biologists to study populations of organisms
• Used to study jewelry
Lesson #3: Exploring Life
Mini Lab
A microscope enables scientists to
study objects in greater detail
than is possible with the unaided
eye. Compare what objects look
like with the unaided eye to those
same objects observed using a
microscope.
Lesson #3: Exploring Life
1. Examine a sea sponge, a leaf, and salt
crystals. Draw each object in your Science
Journal
2. Observe microscope slides of each object
using a microscope on low power.
3. Draw each object as it appears under low
power.
Lesson #3: Exploring Life
Analyze and Conclude
1. Compare your sketches of the
object observed wit your unaided
eye and observed with a
microscope.
2. Explain how studying an object
under a microscope might help
you understand it better.
Science Journal #8
Exploring Life
1. How did microscopes change out ideas
about living things?
1. What are the types of microscopes and how
do they compare?
Inquiry Lab:
Constructing a Dichotomous Key
How can you create a dichotomous key to
identify objects?
Inquiry Lab:
Constructing a Dichotomous Key
Analyze and Conclude
1. Was the other team about to correctly
identify the collection of objects using your
dichotomous key? Why or why not?
2. Summarize how dichotomous keys are useful
in identifying unknown objects.