TEKS BIOLOGY 4 A
Prokaryotic and Eukaryotic Cells
TAKS Objective 2
– The student will demonstrate an understanding of living systems and the
environment.
TEKS Science Concepts 4 A
The student knows that cells are the basic structures of all living things and have specialized
parts that perform specific functions, and that viruses are different from cells and have different
properties and functions. The student is expected to:
(A) identify the parts of prokaryotic and eukaryotic cells
3F
The student uses critical thinking and scientific problem solving to make informed decisions.
The student is expected to:
(F) research and describe the history of biology and contributions of scientists.
For Teacher’s Eyes Only
Teacher Background:
Prokaryotes –
Eukaryotes –
Cell Wall
Centrioles
Chromosomes
Cilia or Flagella
Endoplasmic Reticulum
Golgi Complex
Lysosomes
Mitochondria
Nucleus
Peroxisomes
Plasma Membrane
Ribosomes
The cellular membrane is a very complex, dynamic organelle. Because of its microscopic complexity
and dynamic ability, many of its abstract qualities (i.e. fluidity) have been difficult for students to grasp.
The cellular membrane is an organelle that is found in all living organisms whether they are prokaryotic
(without a nuclear membrane) or eukaryotic (with a nuclear membrane). Its structure is unique and
assists the cell in major functions such as transport, energy generation and synthesis of molecules.
Cell Membrane Structure:
The cell membrane primarily consists of a phospholipids bilayer and proteins dispersed throughout these
two layers.
Photo : www.che.vt.edu/Sum/images/cell-membrane.gif
Cell Membrane Function:
The primary function of the cell membrane is to maintain a barrier between the inside of the cell and the
outside of the cell. This barrier, however, it selectively permeable or has the ability to allow some
things to pass through while not allowing other molecules through. Second, the membrane acts to
transport these molecules across the membrane using the proteins dispersed across the surface
(peripheral proteins) and through the membrane. Most of the proteins that are used in transport
typically span the whole membrane (integral proteins), making contact with the outside environment
and the cytoplasm. There are three basic types of transport systems that the cell using to maintain
homeostasis:

Passive Diffusion (No Energy) i.e. Osmosis – movement of water

Facilitated Diffusion (No Energy) i.e. Large Sugar Molecules (High to Low Concentration)

Active Transport (Uses Energy) i.e. Against Concentration Gradient (Low to High)
Student Prior Knowledge
7.9) Scientific Concepts. The student knows the relationship between structure and function in living
systems. The student is expected to:
(A)
identify the systems of the human organism and describe their functions; and
(B)
describe how organisms maintain stable internal conditions while living in changing external
environments.
8.6) Scientific Concepts. The student knows that interdependence occurs among living systems. The
student is expected to:
(A)
describe interactions among systems in human organism; and
(B)
identify feedback mechanisms that maintain equilibrium of systems such as body temperature,
turgor pressure, and chemical reactions; and
Cells
5 E’s
ENGAGE
EXPLORE
Exploration 1
Plant vs. Animal Lab
Students will observe different types of plant and animal cells under the microscope and record their
observations.
Exploration 2
Gel Cells
When a cell becomes too large, it is no longer as efficient as it used to be. It now has a greater volume
and it takes much longer for materials that enter the cell to reach the center of the cell. This concept will
be demonstrated in the lab. Students will build a model of a cell to understand why cells when they
reach a certain size stop growing.
Exploration 3
Edible Model Cells
Modified from The Incredible, Edible Cell by Todd Howard & Nick Hoffman Wallace High School
Using their textbook and other resources, students will make a model of a prokaryotic and eukaryotic
cell using gelatin and other edible materials. The gelatin will represent the cell membrane/cytoplasm
and other edible components will be representative of the cellular organelles. The three-dimensional
structure of the gelatin cells will reinforce the appearance and functions of the various organelles.
Preparation:
1. Using a light colored flavor of gelatin mix, mix up enough mixture to allow a pair of students a
cell. Every 6 oz package will make up 4 or 5 cells.
2. Add unflavored Knox gelatin to the gelatin mix to provide a more firm consistency.
3. Pray the inside of 9 oz plastic cups with non-stick cooking
4. Pour in the Jello®/Knox mixture until they are about two-thirds full.
5. Put them into a refrigerator overnight to set
6. Obtain food materials to represent the organelles:









fruit roll ups or folded hard ribbon candy .. Golgi Bodies
sour gummy worms with a rough sugar coating .. Rough Endoplasmic Reticulum
1 teaspoon of round cake sprinkles .. Ribosomes
raisins .. Mitochondria
blue jaw breakers .. Vacuoles
1 gum ball .. Nucleus
M & M candy ..Lysosomes
Gumdrops..centrosomes
Cilia and Flagella
Day of Activity:
For each group, provide the following:





1 Jello/Knox mixture in plastic cup
1 paper plate
1 small Dixie cup full of cell parts (organelle) materials
1 plastic knife
1 plastic spoon
EXPLAIN
Review parts of eukaryotic and prokaryotic cells using “The Cell” PowerPoint presentation. Using their
textbooks and notes, have students complete the “Organelles Structure and Function” paper
Organelles
Structure and Function
Organelle
Cell Wall
Centrioles
Chromosomes
Cilia or
Flagella
Endoplasmis
Reticulum
Golgi Complex
Lysosomes
Mitochondria
Nucleus
Peroxisomes
Plasma
Membrane
Ribosomes
Vacuoles
Function
Illustration
Found
in Plant
Animal
Both
Found in
Eukaryote
Prokaryote
Both
Cell Organelles
Direction: Match the correct organelle to the given description using your notes. Each organelle can be
used more than once. The word bank can be found at the bottom of each page.
1. This organelle is found mostly in plants and protists. It helps the cell maintain its water balance.
2. An extra structure that surround the cell membrane and give plants structural support.
3. This is the only organelle that is not surrounded by a membrane.
4. If a cell needs to produce more energy, then it would have many of this type of organelle.
5. This organelle is only found in organisms that photosynthesize. It contains chlorophyll that allows
energy from the sun to be changed into carbohydrates.
6. The purpose of this organelle is to detoxify poisons in the cell.
7. A series of flattened sacs that modifies, packages, stores, and transports materials out of the cell.
8.
This organelle is the only organelle other than the nucleus that contains its own DNA.
9. These non-membrane bound organelles either can be free floating or attached to endoplasmic
reticulum. These organelles are often called protein “factories”
10. A complex network of transport channels that contain ribosomes and releases newly made proteins
from the cell.
11. Instrumental in recycling cellular debris and contains a variety of digestive enzymes.
12. Sacs that help in food digestion or helping the cell maintain its water balance. Mostly found in plant
cells.
13. Gives support to animal cells by giving it its shape and helps with the movement of its organelles.
14. Made of cellulose, chitin, and peptidoglycans.
15. Considered the boundary of both plant and animal cells.
A. Lysosomes
D. Rough ER
AD. Mitochondria
CD. Plasma Membrane
B. Golgi Apparatus or Body C. Smooth Endoplasmic Reticulum (ER)
AB. Ribosome
BC. Nucleus
ABC. Cell Wall
AC. Chloroplast
BD. Nucleolus
ADC. Cytoskeleton
BA. Vacuole
TAKS Objective 2
page 7 TEKS 7.9 A
ELABORATE
Modeling the Animal Cell
In this activity, students will create a diagram of a cell that shows the major
organelles and their functions. By following the procedure, students will create a
closed circuit using a battery, wires, paper spreaders, and an LED light that will
turn on when they match up the organelle with its correct function
Materials
Each group should have the following materials at its lab station:
 Poster board
 Diagram of the cell
 Glue
 Envelope containing organelle words and descriptions
 11 wires
 20 paper spreaders
 1 LED (light) and battery
 Scissors
 Dissecting pin (to poke holes in the poster board)
EVALUATE
1. The students will create an edible cell model and correctly identify the
location and function of at least 8 organelles.
2. The students will correctly match at least 10 organelles with their function,
using the animal and plant cell model.
3. The students will draw and label both a prokaryotic and a eukaryotic cell.
Pass/Fail
4. The students will complete a Venn diagram comparing both prokaryotic
and eukaryotic cells showing at least two differences.
TAKS Objective 2
page 8
TEKS 7.9 A
TAKS Objective 2
page 9
TEKS 7.9 A
Plant vs. Animal Cell Lab
1. The letter ‘e’
a. Cut out the smallest ‘e’ you can find from the magazine provided
b. Place one drop of water on the slide
c. Place a coverslip on the slide
d. Place it on the stage of your microscope
5. Viewing the letter ‘e’ under the lowest magnification, carefully move the
slide to the left. Which direction does the image
move?________________
6. Move the slide to the right? Which direction does the image move?
_____________
7. Move the slide up. In which direction does the image move?___________
8. Move the slide down. In which direction does the image
move?______________
9. View the letter ‘e’ under lowest magnification. Draw it below. Don’t
forget all the things you need to have in a drawing.
TAKS Objective 2
page 10
TEKS 7.9 A
10. View the letter ‘e’ under the highest magnification that your microscope
will allow you to focus. Draw it below. Don’t forget all the things you
need to have in a drawing.
11. Looking at your answers to #8-10 what can you say about what the
microscope does to the image of the object?
____________________________________________________________
____________________________________________________________
____________________________________________________________
____________
12. Looking at your drawing in #11, what can you say about the texture of
paper?______________________________________________________
____________________________________________________________
____________
13. Clean slide with paper towel, throw away ‘e’ and paper towel once the
slide is dry.
TAKS Objective 2
page 11
TEKS 7.9 A
14. Obtain a small slice of onion skin or Elodea from the teacher. Place it on
the middle of the slide. Add a drop of water then the cover slip. View it
under the microscope at the lowest magnification. Draw it below.
15. Pick up the cover slip and add a drop of iodine. Place the coverslip back
on the slide and view it under the microscope at the lowest magnification.
Draw it below.
TAKS Objective 2
page 12
TEKS 7.9 A
16. Looking at the difference between the onion and Elodea without iodine
and with iodine why do you think we use iodine in this lab?
____________________________________________________________
____________________________________________________________
____________________________________________________________
____________________________________________________________
____________________________________________________________
____________________________________
17. Clean off the slide using a few drops of water and a paper towel. Throw
away the paper towel as well as the onion or Elodea when the slide is dry.
18. Use a toothpick (in the Petri dish) to gently scrape the inside of your
cheek. Wipe the slide with toothpick and then THROW THE
TOOTHPICK AWAY!!!!
19. View the slide under the microscope under medium magnification and
draw what you see below:
TAKS Objective 2
page 13
TEKS 7.9 A
20. Pick up the cover slip and now add a drop of methylene blue to the slide
and then replace the cover slip. View the slide under lowest magnification
and draw it below:
21. Why do you think we use methylene blue?
22. View the slide under the highest magnification that your microscope will
allow you to see. Draw it below:
TAKS Objective 2
page 14
TEKS 7.9 A
23. What are some of the differences between cheek and onion cells?
____________________________________________________________
____________________________________________________________
____________________________________________________________
____________________________________________________________
____________________________________________________________
____________________________________________________________
____________________________________________________________
24. Clean off the slide using a couple of drops of alcohol. Throw away the
paper towel and any used toothpicks.
25. Look at the stereoscopes that the teacher has set up. In the space below,
complete the Venn diagram of the 2 kinds of microscopes.
TAKS Objective 2
page 15
TEKS 7.9 A
26. Use the remainder of the class period looking at various slides that the
teacher has provided. Draw what you see at the lowest magnification in
the spaces below. Make sure you return the slides to the teacher before
leaving.
TAKS Objective 2
page 16
TEKS 7.9 A
Agar Gel Cells
Overview:
When cells reach a certain size, their rate of growth slows down. They will
eventually stop growing. Each of these cells divides into two smaller cells, which
begin to grow. What causes this? An easy way to investigate such questions is to
build models. A model is often thought of as a small copy of something larger.
Here we will be making a larger model of something small.
When a cell becomes too large, it is no longer as efficient as it used to be. It now
has a greater volume and it takes much longer for materials that enter the cell to
reach the center of the cell. This concept will be demonstrated in the lab. You will
build a model of a cell to understand why cells when they reach a certain size stop
growing.
Materials:
Block of bromothymol blue agar
Plastic knife
100 ml of acid solution
plastic spoon
beaker 250ml
millimeter ruler
paper towel
Procedure:
1. Obtain 3 cubes of agar per group of four and cut them as follows. The first cube
should be 3cm on each side; the second, 2 cm on each side; and the third, 1 cm on
each side. Measure carefully and trim away the waste. Examine the cubes. Think
of them as giant models of tiny cells.
Materials used during cell activity and growth enter the cell from the outside and
must travel through the cell to their destination. Waste products go through the
cell surface to the outside.
Do you think the cell with the greatest total surface area will do the best job of
moving materials in and out of the cell? Why or why not?
TAKS Objective 2
page 17
TEKS 7.9 A
2. Calculate the total surface area of each of your three models using the
following formula:
Surface area = 6 x (length x width), that is, the total surface area is 6 times the
surface area of one side.
Cell 1:
Cell 2:
Cell 3:
Which cell has the greatest surface area?
3. The cells have different surface areas and they have different volumes
(amounts of materials inside).
Calculate the volume of each cube. Volume = length x width x height.
4. Place the cubes in the beaker. Pour enough acid solution to cover them. Record
your starting time. Use the plastic spoon to turn the cubes often for the next 4
minutes. Be careful not to cut or scratch the surface of the cubes. Blot them dry.
5. Slice each cube in half with the plastic knife.
TAKS Objective 2
page 18
TEKS 7.9 A
Draw a 3cm, 2cm and 1cm square below and draw what you see.
Measure the distance from the edge that the acid solution traveled record the data
below.
Cell 1:
Cell 2:
Cell 3:
6. Calculate the ratio of surface area to volume for each cube. To do this, for each
cube size, divide its surface area by its volume. The number obtained can be
expressed as a ration. For example, a surface area of 24cm2 divided by a volume
of 3 cm3 = 24/3 = 8/1 = 8:1. 7. Fill in the following data chart with your all your
calculations.
Which cell model is the most efficient? Why?
How does this demonstrate why larger cells would want to divide?
DATA TABLE: Cell size comparison.
Cell Dimensions Surface Area Volume
Ratio
(cm)
(cm2)
(cm3) Surface area to Volume
1
2
3
TAKS Objective 2
page 19
TEKS 7.9 A
Edible Cells
Overview:
Using you textbook and other resources, you will make a model of a prokaryotic
and eukaryotic cell using gelatin and other edible materials. The gelatin will
represent the cell membrane/cytoplasm, while the other edible components will be
representative of the cellular organelles.
You will get to choose which candies will represent different organelles. Then
you will explain to your teacher which candy represents each organelle and why
and explain each organelles overall function for the cell.
Procedure for Activity:
1. Obtain two cups of gelatin from your teacher.
2. One cup of gelatin will represent a eukaryotic cell and the other a
prokaryotic cell.
3. Remove the gelatin from the plastic cup onto the paper plate.
4. Cut the gelatin in half as shown in the picture below and remove the top
half.
Turn over the top and set it on the plate beside the bottom half as shown in
Picture 1.
Picture 1
5. Use the spoon to dig out a hole in the bottom half of the gelatin cytoplasm
(Picture 2). Just pushing the food pieces into the gelatin causes it to crack
and come apart, making for a very messy cell. Place the gumball in this
hole to represent the nucleus of the cell.
TAKS Objective 2
page 20
TEKS 7.9 A
Picture 2
6. Using the spoon to make spaces and your diagram as a guide, determine
which pieces of candy will represent the other cellular organelles. Then
place the other cell parts into the cell. Parts can be put into both the top
and bottom half of the gelatin cell.
7. Take the top part of the cell and carefully place it on the top of the bottom
half. If the cell feels soft, you can put the parts back into the plastic cup,
and then turn it over onto the correct place on your paper for your teacher
to evaluate.
8. After the teacher reviews the parts of the cell one final time, students can
eat their cells if they wish. Provide students with clean spoons.
TAKS Objective 2
page 21
TEKS 7.9 A
Eukaryotic Cell
Candy
Organelle
Prokaryotic Cell
Function
TAKS Objective 2
Candy
page 22
Organelle
TEKS 7.9 A
Function
Venn Diagram
Compare Eukaryotes to Prokaryotes
Eukaryotes
Prokaryotes
TAKS Objective 2
page 23
TEKS 7.9 A
Organelles
Structure and Function
Organelle
Function
Illustration
Cell Wall
Centrioles
Chromosomes
Cilia or
Flagella
Endoplasmis
Reticulum
Golgi
Complex
Lysosomes
Mitochondria
Nucleus
Peroxisomes
Plasma
Membrane
Ribosomes
Vacuoles
TAKS Objective 2
page 24TEKS 7.9 A
Found
in Plant
Animal
Both
Found in
Eukaryote
Prokaryote
Both
Animal Cell Light Up
Overview:
You are going to create a diagram of a cell that shows the major organelles and
their functions. When you match up the organelle to the correct function, the light
will turn on. In order to make this work, you must follow these directions very
carefully. By following the procedure, you will create a closed circuit using a
battery, wires, paper spreaders, and an LED.
Materials
Each group should have the following materials at its lab station:
 File Folders
 Diagram of the cell
 Glue
 Envelope containing organelle words and descriptions
 11 wires
 20 paper spreaders
 1 LED (light) or Christmas Tree Lights and battery (two AA in series)
 Scissors
 Hole Punch (to poke holes in the poster board)
Procedure
A. Getting started
1) Open the envelope and separate the organelles from the descriptions.
2) On your lab table, match up each organelle with the correct description.
3) Do not proceed to the next step until you teacher has given you the ok.
B. Labeling the organelles
1) Glue the diagram of cell onto your file folder
2) In pencil, draw a line from the organelle to the outside of the cell.
3) Place the correct name of the organelle at the end of this line.
4) Do this for each organelle.
5) After you have gotten the ok, glue the labels in place and trace over the
lines with marker.
C. Putting the descriptions in place
1) Now you can glue the descriptions onto your board. The goal is to place
them in random fashion so that when you find the organelle, you have to
look for its description. This is a way of quizzing yourself.
2) Follow these guidelines:
 Don’t put the description right next to the organelle.
 Don’t put the description too far away from the organelle because you
may not have enough wire to connect them.
TAKS Objective 2
page 25
TEKS 7.9 A
D. Putting the brackets in place
1) Using the hole punch, carefully punch a hole through the file folder next to
each organelle label and each description.
2) Insert a paper spreader in each hole.
4) Flatten the spreader on the back of the poster so that it stays in place.
3) Once you have a paper spreader next to each organelle label and
description, raise your hand to have your teacher check your work.
E. Wiring the diagram
Important: Wire each organelle ONE at a time to avoid wiring mistakes.
1) Wrap one end of the wire around the paper spreader for the organelle
label.
2) Wrap the other end of the wire around the description for that organelle.
3) Repeat this for each organelle label and description.
F. Probes
1) Using the hole punch, punch two more holes side by side to one another a
few inches from the bottom of the diagram.
2) Insert a paper spreader into each hole.
3) Take your first probe wire and wrap it around the left paper spreader on the
FRONT of the poster.
4) Take your second probe wire and wrap it around the right paper spreader on
the FRONT of the poster.
G. The Light and the Battery
1) Using the hole punch, punch another hole above the cell diagram in the
center of the poster.
2) Using the tip of your pencil or pen, make the hole big enough so that your
LED can be inserted FROM THE BACK. If you try to insert it from the
front, you may damage the LED. There are no extras!
3) Once the LED is in place VERY CAREFULLY secure it by flattening
each side.
4) Use masking tape to secure the battery.
5) Wrap the wire on the left side of the battery to the left probe paper
spreader.
6) Wrap the wire on the right side of the battery to the right probe paper
spreader.
H. The test
1) Now it’s time to see if it works.
2) Touch the left probe to an organelle label paper spreader.
3) At the same time, take the right probe and touch it to the organelle
description paper spreader.
4) If you have followed the directions, the light will turn on! (If your light
doesn’t work- don’t panic. We will try to get it going.)
TAKS Objective 2
page 26
TEKS 7.9 A
Evaluation
Now switch your cell with three other group members and test your
knowledge.
TAKS Objective 2
page 27
TEKS 7.9 A
Images obtained from: http://fig.cox.miami.edu/~cmallery/150/life/plant_cell.jpg
TAKS Objective 2
page 28
TEKS 7.9 A
Organelle Labels and Descriptions
Animal Cell
Organelle
Description
Mitocondrion
 Breaks down sugar molecules into
energy called ATP
Peroxisomes
 Break down fatty acid molecules
 Rids the cell of toxic peroxides
Centrioles
Microfilaments
Microtubules
Lysosomes
Golgi Apparatus
TAKS Objective 2
 Made of microtubules
 Anchor spindle fibers during cell
division
 Only found in animal cells
 Small thread-like material that
provides the cell with shape and
support
 Can play a part in cell movement
(muscle contraction, ameboid
 movement,
Larger tubesand
thatcell
aredivision)
a part of the
cytoskeleton
 Provides the cell with shape and
support
 Breaks down larger food molecules
into smaller food molecules
 Digests old cell parts
 Filled with digestive enzymes
 Store and package cellular secretions
for export out of the cells.
page 29
TEKS 7.9 A
Cilia/Flagella
Nucleus
Rough Endoplasmic Reticulum
Smooth Endoplasmic Reticulum
Ribosomes
Plasma Membrane
Cytoplasm
TAKS Objective 2
 For single cells, such as sperm, this
enables them to swim.
 For cells anchored in a tissue, like the
epithelial cells lining our air
passages, this moves liquid over the
surface of the cell (e.g., driving
particle-laden mucus toward the
throat).
 Controls all cellular activity
 Carries materials, primarily proteins,
through the cell
 Ribosomes on surface
 Transport proteins to Golgi Apparatus
for packaging
 Long canals that carry materials
through the cell
 NO ribosomes on its surface
 Detoxifies the cell
 Produce Proteins
 Can be free-floating or attached to
endoplasmic reticulum
 Barrier that supports and protects the
cell
 Controls movement of materials
in/out of the cell
 Maintains homeostasis
 Supports and protects cell organelles
page 30
TEKS 7.9 A
Organelle Labels and Descriptions
Plant Cell
Organelle
Description
Mitocondrion
 Breaks down sugar molecules into
energy called ATP
Peroxisomes
 Break down fatty acid molecules
 Rids the cell of toxic peroxides
Microfilaments
Microtubules
Golgi Apparatus
Nucleus
Rough Endoplasmic Reticulum
TAKS Objective 2
 Small thread-like material that
provides the cell with shape and
support
 Can play a part in cell movement
(muscle contraction, ameboid
 movement,
Larger tubesand
thatcell
aredivision)
a part of the
cytoskeleton
 Provides the cell with shape and
support
 Store and package cellular secretions
for export out of the cells.
 Controls all cellular activity
 Carries materials, primarily proteins,
through the cell
 Ribosomes on surface
 Transport proteins to Golgi Apparatus
for packaging
page 31
TEKS 7.9 A
Smooth Endoplasmic Reticulum
Ribosomes
Plasma Membrane
Cytoplasm
Tonoplast
Central Vacuole
Plasmodesmata
Chloroplast
 Long canals that carry materials
through the cell
 NO ribosomes on its surface
 Detoxifies the cell
 Produce Proteins
 Can be free-floating or attached to
endoplasmic reticulum
 Barrier that supports and protects the
cell
 Controls movement of materials
in/out of the cell
 Maintains homeostasis
 Supports and protects cell organelles
 Membrane surrounding the central
vacuole
 Store foods (e.g., proteins in seeds)
 Store wastes
 Store various ions (e.g., calcium,
sodium, iron) which, among other
functions, helps to maintain turgor in
the cell.
 Act as bridges that connect one cell
wall to another.
 Contain chlorophylls giving them a
green color
 Contain the pigments that harvest the
light used in photosynthesis
 Very strong barrier made of cellulose
Cell Wall
TAKS Objective 2
 Prevents plant cells from bursting in
hypotonic surroundings. Allows the
build-up of turgor within the cell.
Loss of turgor causes wilting.
page 32
TEKS 7.9 A
TAKS Objective 2
page 33
TEKS 7.9 A