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Cell Structure
Subject: Science
Grade: 6
Time Required: 6 Class Periods
Content TEKS and Clarifiers:
6.10 The student knows the relationship between structure and function in living
systems. The student is expected to:
(A) differentiate between structure and function;
(B) determine that all organisms are composed of cells that carry on functions to sustain
life
Educational Objective:
What the student must know:
All living things are made up of cells. Cells contain different parts that have
specific jobs or functions, including genetic material. Plant and animal cells
have many common structures, but only plant cells have chloroplasts and cell
walls.
What the student must do:
Use a microscope to observe different types of cells, and complete labeled
cell drawings showing the parts of cells. Compare and differentiate between
animal and plant cells using a Venn diagram. Represent cells and cell parts by
creating a 3-dimensional model and an analogy of cell parts and functions.
More Information:
For more information see the TRIAND Resources icon for this SE.
Vocabulary:
Cell
Cell wall
Cell membrane
Nucleus
Mitochondria
Chloroplasts
Vacuoles
Cytoplasm
NOTE: Students should be able to define vocabulary words from their
learning experiences. More detailed information is found in the teacher
background section.
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For ideas on teaching vocabulary, refer to the TRIAND resources icon to
select District Strategies: Verbal/Visual, Automaticity, etc.
Procedures:
ENGAGE
1.
2.
3.
4.
5.
6.
7.
8.
9.
Materials:
Ask students how many grains of sand they think might be on
White board or
the beach in Galveston.
chalkboard (T)
Tell students that humans are made of billions of tiny parts
White board
just as the beach is made up of many tiny grains of sand.
markers or chalk
Write the word cell on the board.
(T)
Ask students if they recognize the word cell, and what it might
Microscopes (L)
mean. (Accept all responses for now.)
Microscope slides
Pass out microscopes, microscope slides and paper thin slices
(L)
of cork (The cork must be precut by the teacher prior to class.)
Cork (L)
Tell students to make a dry slide of the cork and to look at the
Razor or scalpel (T)
cork under the microscope. (Remind students to start with low
Science journals (I)
power and then go to medium and high power.)
Pen or pencil (I)
Ask students what they see. (They should see little areas that
look like little rooms surrounded by thin walls – any
description is okay.)
Explain to students that Robert Hooke, an English scientist, was one of the first people to
see cells under a microscope. He called them cells because they looked like little rooms in
a prison or a monastary. (Explain to students that rooms in a prison or a monastary are
referred to as cells if they have any questions about the name.)
Ask students why they think the cells might be empty. (The cork is dead, so students are
looking at the cell wall and air space.)
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EXPLORE
1.
2.
3.
4.
5.
6.
7.
8.
Tell students they will be looking at some living cells under the
microscope. Explain that each one is a different type of cell.
(Don’t tell them what each type is until later.)
Pass out lab activity sheet and read instructions with students.
Review safety rules for cutting with sharp objects and use of
goggles and laboratory aprons when staining onion slides. Iodine
stains clothing! Review microscope procedures, including
carrying a microscope with one hand on the arm and one hand
under the base.
Distribute materials to each group. Designate a central location
for the onion slide preparation to allow careful monitoring of
student use of scalpels and iodine stain. Equip it with slides,
coverslips, cut onion slices, droppers, iodine and paper towels.
Tell students they have the materials for viewing the onion slide.
Designate other areas in the room as a pick up station for the
pond water and animal slides. After completing the onion slide
observation and drawing, students may view the prepared animal
and pond water slide. Monitor students for proper microscope
use.
Remind students to draw what they observe in their journal.
Students will come back to the drawings and label parts later in
the lesson, so no labels are needed on the drawings at this point.
After all students are finished, ask them to describe each slide.
Explain what each of the types of cells are. (Onion – plant cell,
Pond water – Protists, and prepared animal slide – animal)
Have students clean and put away all materials.
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Materials:
Student activity
sheets (I)
Microscope (L)
Onion (T)
Razor or scalpel (T
or L)
Iodine (L)
Dropper (L)
3 microscope slides
(L)
3 coverslips (L)
Apron (I) – for
student staining
slide
Goggles (I) for
student staining
slide
Paper towels (L)
Glass with pond
water (T) with
dropper
Prepared animal
slide (L)
Tweezers (L)
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Cell Structure
Materials:
Whiteboard or
chalkboard (T)
Markers or chalk
(T)
Textbook (I)
Science journal (I)
Pencil (I)
Map pencils or
colors (I)
EXPLAIN
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
Write the following words on the board: vacuole, cell wall,
cytoplasm, cell membrane, chloroplasts, mitochondrion, and
nucleus.
Ask students to turn to page 142 in their Prentice Hall Science
Explorer textbook.
Ask students which cell they observed was most similar to the
diagram. (onion)
Explain to students page 142 shows a diagram of a plant cell and
its cell parts. Explain that they are not responsible for all of the
cell parts – only vacuole, cell wall, cytoplasm, cell membrane,
chloroplasts, mitochondrion and the nucleus.
Ask students if the onion cell looked exactly like the plant cell in the book. Point out that
the cell in the book is a diagram which shows the parts illustrated in different colors so
students can easily tell them apart. Also, some parts were probably not visible under the
microscope. However, they should have seen the nucleus, chloroplasts, cell wall, cytoplasm
and cell membrane.
Ask students to look at the animal cell on page 143.
Ask students if any of the cells they looked at were similar to this one? (prepared animal
slide)
Tell students to make a color drawing of a plant and an animal cell in their science journal,
using the text as a reference. Ask students to draw and label only the parts listed on the
board
After students complete their drawings, ask them what parts the plant and animal cells have
in common. (vacuole, cytoplasm, cell membrane, mitochondrion and nucleus)
Tell students to look at the information under vacuole for both plant and animal cells. Ask
them to use this information and the diagrams. How are vacuoles in plant cells different
from those in animal cells? (plants usually have one large vacuole, some animals cells have
many small vacuoles; some cells do not have as many vacuoles)
Ask students what is different about the plant and animal cells? (shape – plant cell is
square, animal cell is rounded; plant cell has a cell wall for support and chloroplasts for
photosynthesis)
Ask students to look at the information under “chloroplasts.”
Ask why an animal cell would not need chloroplasts. (chloroplasts are for producing food,
animals do not produce their own food)
Ask students to go back into the text and find the function (job) of each of the parts of the
cells. (pages 139 – 145) and write the function of each cell part next to the labels on their
diagrams.
Tell student to turn back to the Explore cell drawings in their journals and label any parts
they saw under the microscope.
Ask students to create a Venn diagram in their science journal comparing and contrasting
plant and animal cells.
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Cell Structure
ELABORATE
1.
2.
3.
4.
5.
6.
7.
8.
Materials:
Show students a picture of an apple, and then show them an apple.
Part A:
Use the apple as an example of a 3 dimensional object, and the
Small boxes (check
picture of the apple as a 2 dimensional representation of the apple.
boxes) (L)
Ask students if the cells they observed were 2 or 3 dimensional.
Small ziplock bags
Explain to students that cells are 3 dimensional. They are not flat.
(L)
They just appear flat when viewed under a microscope because they
Karo syrup (L)
are so small.
Beads (L)
Explain to students they will make a model of what a cell might
Marbles (L)
really look like if it were larger.
Yarn (L)
Provide students with materials such as small ziplock bags, Karo
Any other materials
syrup, small boxes, marbles, beads, yarn, pipe cleaners and other
you deem
readily available materials for organelles.
appropriate (L)
Assign half of the lab groups to create a plant cell and half to create
Textbook (I)
an animal cell.
Picture of an apple
Guide the students with cell membrane (baggie), cell wall (box) and
(T)
cytoplasm (syrup.) The rest of the parts should be up to the students. Apple (T)
After students are finished with their cell models, ask them to label
each part and construct a key to show what each material represents. Ask students to
explain how the cell models are different from the cells they observed under the
microscope. Explain to students that these are MODELS of cells but that models can often
be used to help us study things that are too small to see. Display the cell models.
EVALUATE
1. Ask students to describe the function or job of the nucleus. (The nucleus acts as the “brain”
of the cell and provides instructions for the cell to follow.)
2. Ask students if they can think of examples of other people or objects
Materials:
that provide important instructions to follow. (President, parents,
Textbook (I)
principal, computer are possible answers)
Old magazines (I)
3. Go over the function (job) of each of the parts with students. (Cell wall Markers (I)
provides shape, and protects and supports the cell; Cell membrane
Glue (I)
controls what goes into and comes out of the cell; Mitochondrion
Large construction
produce the energy for the cell; Chloroplasts are used to produce
paper (I)
food; Vacuoles store food, water and waste products; Cytoplasm
contains all the parts of the cell – keeps everything in its place)
4. Ask students to think of something or someone who might have a job that is similar to the
cell parts.
5. Have students work in partners to create a collage to show the functions (jobs) of each of the
cell parts. (ex: cell wall gives shape, protects and supports the cell – bricks around a
building; cell membrane controls what goes into and comes out of the cell – border between
countries; mitochondrion produce the energy for the cell – a power plant, electricity, food;
chloroplasts are used to produce food – stove, chef, McDonald’s; vacuoles store food and
water <also waste products> - refrigerator, septic system; cytoplasm contains all the parts
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Cell Structure
of the cell and keeps everything in place –building, classroom ) Make sure each picture is
labeled with the cell part.
6. As an extension, you may have students write why they used a particular picture to represent
each cell part function (job).
7. Have students share their collages, explaining why they chose the pictures to represent each
cell part. Use the rubric to evaluate the student’s data sheet for the cell structure
investigation.
Building A Model : Cell
Use the following rubric to evaluate the student’s cell model.
Lab Report : Cell Structure
Student Name:
CATEGORY
________________________________________
4
3
2
1
Used time well
in lab and
focused
attention on the
experiment.
Used time pretty
well. Stayed
focused on the
experiment most
of the time.
Did the lab but
did not appear
very interested.
Focus was lost
on several
occasions.
Participation was
minimal OR
student was
hostile about
participating.
Drawings/Diagrams Clear, accurate
diagrams are
included and
make the
experiment
easier to
understand.
Diagrams are
included - neat.
Diagrams are
included.
Needed diagrams
are missing.
Summary
Summary
accurately
describes the
information
learned
Summary
describes the
information
learned.
No summary is
written.
Participation
Summary
accurately
describes the
skills learned,
the information
learned.
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Use the following rubric to evaluate the student’s cell model.
Making A Model of a Cell
Student Name:
________________________________________
4
3
Construction Materials
Appropriate
materials were
selected and
creatively modified in
ways that made
them even better.
Appropriate
Appropriate
materials were
materials were
selected and there
selected.
was an attempt at
creative modification
to make them even
better.
Inappropriate
materials were
selected to construct
the cell.
Construction Care Taken
Great care taken in
construction process
so that the cell is
neat, attractive and
follows plans
accurately.
Construction was
careful and accurate
for the most part, but
1-2 details could
have been refined
for a more attractive
cell.
Construction
appears careless or
haphazard. Many
details need
refinement for a
strong or attractive
cell.
CATEGORY
2
1
Construction
accurately followed
the plans, but 3-4
details could have
been refined for a
more attractive cell.
Use the following rubric to evaluate the student’s cell analogy.
Making A Collage : Cell Analogy
Student Name:
CATEGORY
Time and Effort
Creativity
________________________________________
4
Class time was
used wisely. Much
time and effort
went into the
planning and
design of the
collage.
Several of the
graphics or objects
used in the collage
reflect an
exceptional degree
of student
creativity.
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3
Class time was
used wisely.
Student could have
put in a little more
time and effort
2
Class time was not
always used
wisely.
1
Class time was not
used wisely.
One or two of the
graphics or objects
used in the collage
reflect student
creativity.
Ideas were typical
rather than
creative.
The student did not
make any effort.
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Cell Structure
Materials Details/Advanced Preparation:
ENGAGE
White board or chalkboard (T)
White board markers or chalk (T)
Microscopes (L)
Microscope slides - 1 (L)
Cork – if you do not want to give the students a scalpel or razor you need to cut these; cut a very
thin slice (L)
Razor or scalpel – number depends on whether teacher or students cut cork (T)
Science journal (I)
Pen or pencil (I)
EXPLORE
Student activity sheet (I)
Microscope (L)
Razor or scalpel – refer to above directions (T or L)
Onion (T)
Iodine (L)
Dropper (L)
3 microscope slides (L)
3 coverslips (L)
apron (I) – or if short supply can be used by student staining slide
goggles (I)
paper towels (L)
tweezers (L)
liver or animal cell slides (commercially prepared) (L)
Container with pond water – try to get pond water several days in advance (T)
Dropper – place in pond water (T)
EXPLAIN
Whiteboard or chalkboard (T)
Markers or chalk (T)
Textbook (I)
Science journal (I)
Pencil (I)
Map pencils or colors (I)
ELABORATE
Picture of an apple (T)
Apple (T)
Small boxes (check boxes or any other small box) (L)
Small ziplock bags (L)
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Karo syrup (L)
Beads (L)
Marbles (L)
Yarn (L)
Any other materials you deem appropriate (L)
Textbook (I)
EVALUATE
Textbook (I)
Old magazines (I)
Markers (I)
Glue (I)
Large construction paper (I)
Rubrics - attached
Teacher Background Information:
All living things are made of cells. Some organisms or living things consist of one cell.
Other organisms, such as humans, are made of many different types of cells. Protists,
bacteria and some fungi are one-celled organisms. A pond water sample will most
likely contain many examples of protists.
One of the first people to observe a “cell” under the microscope was Robert Hooke. He saw the
same things that students will observe when looking at cork under the microscope. Hooke
observed thinly sliced piece of cork with his compound microscope, and called the tiny,
rectangular areas “cells” because they looked like little rooms.
Cells are made up of tiny parts called organelles. Both animal and plant have a nucleus, cell
membrane, cytoplasm, and mitochondria. The nucleus is the control center of the cell and
contains the cell’s genetic material. The cell membrane separates the cell from the outside
world. It allows water and food to enter the cell and waste products to leave the cell. The area
between the cell membrane and the cell contains a material called cytoplasm. Both animal and
plant cells also contain vacuoles. However, a plant cell vacuole is extremely large. Most of the
water in a plant cell is stored in the vacuole. Plants wilt when the central vacuoles of their cells
shrink because of lack of water. Animal cells contain many smaller vacuoles to store food, water
and waste products. The mitochondria are rod shaped organelles known as the “powerhouses”
of the cell – meaning they produce most of the energy the plant needs to carry out its functions.
Cells that need a lot of energy (muscle cells) have many mitochondria. Vacuoles, chloroplasts
and mitochondria are all located in the cytoplasm.
Plant and animal cells have many parts in common, but they are also different in several ways.
Plant cells have a cell wall. The cell wall gives the plant cell its shape. It also protects and
supports the plant cell. Plants also contain large green chloroplasts. Chloroplasts capture light
energy from the sun to produce food by photosynthesis. Animal cells do not contain
chloroplasts.
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Targeted TEKS:
6.1 The student conducts field and laboratory investigations using safe,
environmentally appropriate, and ethical practices. The student is expected to:
(A) demonstrate safe practices during field and laboratory investigations
(B) make wise choices in the use and conservation of resources and the
disposal or recycling of materials.
6.2 The student uses scientific inquiry methods during field and laboratory
investigations. The student is expected to
(B) collect data by observing and measuring
6.3 The student uses critical thinking and scientific problem solving to make
informed decisions. The student is expected to:
(C) represent the natural world using models and identify their limitations
(E) connect Grade 6 science concepts with the history of science and
contributions of scientists.
6.4 The student knows how to use a variety of tools and methods to conduct
science inquiry. The student is expected to:
(A) collect, analyze, and record information using tools including beakers,
petri dishes, meter sticks, graduated cylinders, weather instruments, timing
devices, hot plates, test tubes, safety goggles, spring scales, magnets,
balances, microscopes, telescopes, thermometers, calculators, field
equipment, compasses, computers and computer probes
Additional Documents/Resources:
See District Strategies available on TRIAND.
Science Explorer Grade 6 – Prentice Hall pg 138-146
www.enchantedlearning.com/subjects/plants/cell/
www.enchantedlearning.com/subjects/animals/cell/
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www.enchantedlearning.com/subjects/plants/cell/
www.enchantedlearning.com/subjects/animals/cell/
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Cell Structure
Name
Date:
Period:
LAB
Cell Structure
Introduction:
All living things are made of smaller pieces called cells. Cells are
made of even smaller parts. Both plant and animal cells contain a cell
membrane, nucleus, cytoplasm and mitochondria. Plant cells contain
chlorophyll and a cell wall. Animal cells do not have these parts. Most
animal cells and all plant cells contain a vacuole. Plant cells usually
contain one very large vacuole. Animal cells may contain many smaller
vacuoles.
Purpose:
Describe different types of cells.
Procedures: Onion slide
1.
2.
3.
4.
5.
6.
7.
8.
Put on your apron. You will be using iodine. It stains!
Obtain a small, thin piece of onion from your teacher.
Make a wet mount slide with your onion piece.
Look under the microscope at your onion piece.
What do you see? Write your observation in the data chart.
Remove the slide from under the microscope.
Put on your goggles.
Put a small drop of iodine on one side of the coverslip. The
iodine should slowly flow under the coverslip. Place a paper
towel on the opposite end of the coverslip. This will absorb
the extra iodine.
9. Look under the microscope at your onion piece. What do you
see? Draw what you see in one of the circles. Label the circle
“stained onion.” Write your observations in the data chart.
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Procedures: Pond Water slide
1. Put a small drop on a slide. Put the coverslip over the water.
2. Look at the slide under the microscope.
3. What do you see? Draw what you see in one of the circles.
Label the circle “pond water.”
4. Write your observations in the data chart.
Procedures: Yeast slide
1.
2.
3.
4.
5.
Stir the yeast mixture provided by your teacher.
Put a small drop on a slide. Put the coverslip over the water.
Look at the slide under the microscope.
What do you see? Write your observations in the data chart.
Draw what you see in one of the circles. Label the circle
“yeast.”
6. Clean up your materials and put everything in the proper place.
Data:
Observations
Onion
Stained Onion
Pond Water
Yeast
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Conclusions: (USE COMPLETE SENTENCES)
1.
2.
3.
How are the three cells you observed alike? How are they
different?
What parts did you observe?
Why do you think you might not be able to see all the parts on
these cells?
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