Unit 4
Cells
Name _____________
Period ______
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Key Understandings
1. ______________________________________________________________________________
____________________________________________________________________
2. ______________________________________________________________________________
_____________________________________________________________________
Unit 4 Vocabulary – Part 1
membrane thin, flexible barrier around a cell; regulates what enters and leaves the cell
wall a rigid layer of nonliving material that surrounds the cells of plants and some other organisms
3. chloroplast an organelle found in plant and algae cells where photosynthesis occurs
4. cilia Hairlike projections that extend from the plasma membrane and are used for locomotion
5. cytoplasm a jellylike fluid inside the cell in which the organelles are suspended
6. eukaryote a cell that contains a nucleus and membrane bound organelles
7. flagella whiplike tails found in one-celled organisms to aid in movement
8. Golgi apparatus A system of membranes that modifies and packages proteins for export by the cell
9. lysosome cell organelle filled with enzymes needed to break down certain materials in the cell
10. mitochondria Powerhouse of the cell, organelle that is the site of ATP (energy) production
11. nuclear membrane Thin structure that surrounds and protects the nucleus
12. nucleolus a small round body of protein in a cell nucleus
13. nucleus a part of the cell containing DNA and RNA and responsible for growth and reproduction
14. plastid group of plant organelles that are used for storage of starches, lipids, or pigments
15. prokaryote a unicellular organism having cells lacking membrane-bound nuclei
16. ribosomes non membrane bounded organelles responsible for protein synthesis
17. rough endoplasmic reticulum An endomembrane system covered with ribosomes where many proteins for
transport are assembled.
18. smooth endoplasmic reticulum doesn't have ribosomes and it transports certain lipids
19. vacuole cell organelle that stores materials such as water, salts, proteins, and carbohydrates
20. vesicle small membrane-bound sac that functions in moving products into, out of, and within a cell
1. cell
2. cell
Unit 4 Vocabulary – Part 2
gradient the difference in the concentration of molecules across a distance
The process by which molecules move from an area of higher concentration to an area of lower
concentration
4. endocytosis process by which a cell takes material into the cell by infolding of the cell membrane
5. exocytosis process by which a cell releases large amounts of material
6. facilitated transport Passive Transfer of a substance into or out of a cell along a concentration gradient by a process
that requires a carrier
7. homeostasis process by which organisms maintain a relatively stable internal environment
8. hydrophilic water loving
9. hydrophobic water fearing
10. hypertonic when comparing two solutions, the solution with the greater concentration of solutes
11. hypotonic When comparing two solutions, the solution with the lesser concentration of solutes
12. isotonic describes a solution whose solute concentration is equal to the solute concentration inside a cell
13. osmosis Diffusion of water through a selectively permeable membrane
14. passive transport the movement of materials through a cell membrane without using energy
15. phagocytosis process in which extensions of cytoplasm surround and engulf large particles and take them into the
cell
16. pinocytosis process by which a cell takes in liquid from the surrounding environment
17. protein ion pump an integral protein that can move protons and hydrogen ions across a cell membrane
18. semipermeable membrane allows the passage of some particles while blocking the passage of others
2. concentration
3. diffusion
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Extra Notes Page
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Assignment Discovery – Cells – Video Notes
1. What shape are the skin cells that are viewed under the microscope?______________________
2. What does the pink liquid that the cells are placed in do for the cells?
3. How many years ago was the microscope invented?_______________________
4. What was Robert Hooke looking at under the microscope?_______________________
5. What term did he invent?_________________________________
6. What did Robert Brown call the dark dense blob inside the cell?_________________________
7. Schleiden and Schwann developed the cell theory that said that cells are
________________________________________________________________________.
8. What is the jelly-like substance surrounding the nucleus?__________________________
9. What are some of the things that the cell membrane allows to pass into the cell?
10. What takes place in the cytoplasm?
11. What can nettle be used for?________________________________
12. What is the typical shape of a plant cell?___________________________________
13. What is the structure outside the cell membrane that only plants have? ____________________
14. What are the two raw materials plants need to make food?
15. What are the green blobs that you see in the plant leaf?_______________________
16. How many cells are humans made of?
17. What is the blueprint of life?_____________________
18. What is the name for the bubbles that trap materials the cells need?______________________
19. How long does it take a bubble to reach from the spine to the toe?_____________________
20. The human body all comes down to physics and ____________________.
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History of Cells
Robert Hooke
Cell Theory
1.
2.
3.
Levels of Organization
Largest
Smallest
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Cells
Unicellular vs. Multicellular
Tell the difference between unicellular and multicellular and an advantage of each.
Unicellular:
Uni =
Definition:
Example:
Advantage:
Multicellular:
Multi=
Definition:
Example:
Advantage:
Lab Safety
List 3 safety considerations you will take when doing the microscope lab; looking at cheek and plant
cells.
Label the
microscope
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Microscope Lab
Objectives:
 To learn the parts of the microscope.
 To find specimens using low and high power.
 To make a wet mount.
 To view your own human cheek cells under the microscope.
 To compare plant and animal cells.
Procedure: Letter “e”
1. Cut out the letter “e” and place it on the slide face up.
2. Add a drop of water to the slide.
3. Place the cover slip on top of the “e” and drop of water at a 45-degree angle and lower. Draw
what is on the slide in Figure1.
4. Place the slide on the stage and view in low power (4x). Center the “e” in your field of view.
Draw what you see in Figure 2.
5. Move the slide to the left, what happens? Move the slide to the right, what happens? Up?
Down?
6. View the specimen in high power (10x). Use the fine adjustment only to focus. Draw what you
see in Figure 3.
Data: Part 1- The letter “e”
Figure 1: Drawing of the letter “e” on the slide.
Figure 2: Drawing of the letter “e” in low power (4x).
Figure 3: Drawing of the letter “e” in high power (10x)
Analysis:
1. How does the letter “e” as seen through the microscope differ from the way an “e” normally appears?
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2. When you move the slide to the left, in what direction does the letter “e” appear to move? When you
move it to the right? Up? Down?
3. How does the ink appear under the microscope compared to normal view?
4. Why does a specimen placed under the microscope have to be thin?
Procedure: Part 2 - Cheek Cell
1. Place a small drop of Iodine onto a clean slide.
2. Using a toothpick, gently scrape the inside of you cheek.
3. Place the toothpick tip into the iodine and mix. The iodine stains the cells so you can see them.
4. Place the slide under low power (4x). Draw what you see in Figure 4.
5. Switch to high power (10x). Draw 2 or 3 cells in Figure 5. Label the nucleus, cell membrane, and
cytoplasm.
Data: Part 2- Cheek Cell
Figure 4: Drawing of the cheek cell in low power (4x)
Figure 5: Drawing of the cheek cells in high power (10x) Label the nucleus, cell membrane, and
cytoplasm.
Analysis:
1. Why did we add iodine to our cheek cells?
2. What structure in the cheek cell was stained the darkest?
3. Is your cheek cell an animal cell?
Procedure: Part 3 - The Elodea leaf
1. Place a drop of water on a clean slide.
2. Place an Elodea leaf in the drop of water, place a coverslip on top.
3. Observe under low power first (4x), then under high power (10x) Draw in Figure 6. Label the
following organelles: nucleus, cytoplasm, cell wall, chloroplasts.
Data: Part 3 – The Elodea Cell
Figure 6: Drawing of the Elodea cell in high power (10x)
Analysis:
1. Was anything happening in your cell?
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2. What structures were in the plant and animal cell?
3. What structures were only in the Elodea cell?
Conclusion: 2-3 sentences on what you learned.
Prokaryotic Cells
Prokaryotes – What are they?

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
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Cells (usually ___________________________________) with ________________________
Have ________________ specialized organelles
Usually have: cell wall, cell membrane, _______________________, genetic material,
cytoplasm, and flagella or cilia
Examples: ___________________________ and archae
Reproduce through ___________________________________________
Get energy through _____________________________, chemosynthesis, (inorganic chemicals)
or _______________________ other organisms
Color a prokaryotic cell and Label organelles. Highlight the organelles that are common for
Eukaryotic and Prokaryotic.
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Eukaryotic Cells
Eukaryotes – What are they?



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
Cells ___________________________________ and other
___________________________________________ that perform special functions
_____________________________ have a nucleus
May also have: chloroplasts, Golgi apparatus, lysosomes, mitochondrion, plastids, rough
endoplasmic reticulum, smooth endoplasmic reticulum, vacuoles, and vesicles
Examples: fungi, ________________________, plant and _____________________ cells
Reproduce by ________________________________________________
Get energy through ______________________ or by _____________________ other organisms.
Color a Eukaryotic cell and Label organelles. Highlight the organelles that are common for
Eukaryotic and Prokaryotic.
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Prokaryotic vs. Eukaryotic Cells
PROKARYOTIC
EUKARYOTIC
Mnemonic for remembering Pro vs. Eu
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Cell Pictures
Bacteria
Protista
Animal
Plant
Plant vs. Animal Cells
PLANT
ANIMAL
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Cell Organelles
The definition of an organelle is:
______________________________________________________________________________
Structure/Function
Cell Part
1.
The sites of protein synthesis
2.
Transports materials within the cell
3.
The region inside the cell except for the nucleus
4.
Organelle that controls all the cell functions in a eukaryotic cell
5.
Contains chlorophyll, a green pigment that traps energy from
sunlight and gives plants their green color. Can increase pH
when plant is in water.
6.
Digests excess or worn-out cell parts, food particles and
invading viruses or bacteria
7.
Firm, protective structure that gives the cell its shape in plants,
fungi, most bacteria and some protists
8.
Produces a usable form of energy for the cell
9.
Packages proteins for transport out of the cell
10.
The membrane surrounding the cell; Composed of a
phospholipid bilayer; controls what goes in and out of the cell
11.
Small hair-like structures used for movement or sensing things
12.
Longer whip-like structures used for movement
Organelle
Plant
Animal
Organelle
Cell Wall
Mitochondria
Vesicle
Nucleolus
Chloroplast
Nucleus
Chromatin - DNA
Cell membrane
Cytoplasm
Central vacuole
Cytoskeleton
Ribosome
Endoplasmic reticulum
Vacuole
Golgi apparatus
Lysosome
Plant
Prokaryotic,
Eukaryotic, or
Both
Animal
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Cell City
Draw a “City” and make correlating buildings and organelles. (ex. Mitochondria = factory)
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Endosymbiosis
Endosymbiosis Research Questions:
1. What is endosymbiosis?
2. How does the meaning of the root words “endo-“ and “-symbiosis” help you understand the
meaning of endosymbiosis?
3. How does endosymbiosis play a role in the evolution of prokaryotes to eukaryotes, and how are
mitochondria important to this evolution?
4. What is the evidence scientists have to support endosymbiosis and the evolution of prokaryotes
to eukaryotes?
5. What is another cell organelle that is thought to have originated through endosymbiosis?
6. Could you find free-living mitochondrion today? Why or why not?
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Endosymbiosis
Draw and label a cell going through endosymbiosis.
What will this cell become?
List the evidence that supports endosymbiosis.
1.
2.
3.
4.
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Cell Transport & Homeostasis Notes
Semi-permeable


Allowing __________________________ substances to pass through
Cell membrane is semi-permeable, it allows certain substances to cross but _________________
Homeostasis


Regulation of an organism’s ____________________________________ in order to maintain
conditions suitable for survival
Happens on the __________________ and ____________________ level
Passive Transport

Movement of substances across the cell membrane that ___________________________ from
the cell (high concentration to low concentration)
Diffusion


Movement of particles from an area of _______________ concentration to an area of
________________________concentration
Type of passive transport
Facilitated Diffusion


Substances cross the cell membrane with the help of ________________________________
Type of passive transport
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Osmosis

Diffusion of_______________ from an area of higher concentration to an area of lower
concentration
Hypotonic Solution


A ____________________ or environment surrounding a cell that
_________________________________ and more water than the cell
This type of solution will cause water to move _______________ the cell via osmosis, resulting
in swelling of the cell
Hypertonic Solution


A solution or environment surrounding a cell that has _________________________________
and less water than the cell
This type of solution will cause water to move ______________of the cell via osmosis, resulting
in shrinking of the cell.
Isotonic

A solution or environment surrounding a cell that has the ___________________________ of
dissolved solutes and the same amount of water as the cell
Active Transport

Movement of particles across a membrane to an area of higher concentration, which
______________________________________________
Ion or Protein Pump


Proteins that are able to transport ions across the cell membrane from low to high
concentration by changing their shape which ______________________ (energy) from the cell
Example: sodium-potassium pump (important in nerve responses)
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Endocytosis


Cell _____________________________ a bulky substance from its surroundings by wrapping its
membrane around the substance and forming a vesicle
Ex: White blood cells “eat” bacteria using this process.
Exocytosis


Cell _______________________ substances by merging a vesicle with the cell membrane and
releasing the substances into the fluid around the cell
Ex: cell releases waste products
Double Diffusion Lab
Part 1: Diffusion of Water with Gummy Bears
Purpose: To investigate the movement of water into and out of a gummy bear and relate this movement
to osmosis, hypotonic, isotonic and hypertonic solutions.
Write your Hypothesis:
Background: Gummy bears are made of gelatin and sugar. Gelatin is a protein that adds structural
support to jellies, jams, and many other things you use every day. Diffusion is the movement of
materials from an area of high concentration to an area of low concentration. In this lab you will
measure the movement of water by measuring the change in size of a gummy bear. Based on this
information, formulate a hypothesis for each day of the lab.
Procedure:
DAY 1
1. Obtain 2 plastic cups, 2 gummy bears (the same color), and a ruler.
2. Label each cup with your name and class period using a permanent marker. Then label them #1
and #2.
3. Measure your bear (in mm) from top to bottom (length), from side to side (width), and from
front to back (height). Also obtain the mass (g). Record these data in your data table.
4. Place a bear in each cup and fill the cups half way with water. Add 15 grams of salt to cup #2.
5. Place the cups in the designated area for 24 hours.
6. Calculate the volume of each bear (l x w x h).
DAY 2
7. Use a plastic spoon to gently scoop out each bear. BE CAREFUL not to break the bears, they are
very fragile.
8. Measure the length, width, height and mass and record in your data table.
9. Make any observations about the color of the bears and/or the water.
10. Calculate the volume of each bear on Day 2 and record the mass
11. Calculate percent change.
Day 2 volume – Day 1 volume
X 100 = %change
Day 1 volume
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Copy down the following tables beneath your hypothesis:
Post Lab Analysis:
1. What happened to the bears after being initially placed in water? (Look at your Day 2 results.) Explain
the direction of water movement.
2. What happened to the bear that was placed in the salt water? Compare the direction of osmosis with
the bear that was in the water only. Explain this disparity.
3. Explain any change in color in the bears or their solutions. Describe the movement of water that
produced the results.
4. What do you predict would eventually happen to the bear in cup #1 if it was left in the water for a few
more days?
5. Compare you data with the rest of the class. Did color appear to be a factor in the lab? If so, which
color(s) changed the most in size from Day 1 to Day 2?
6. Explain the types of solutions you worked with on each day. Were the solutions hypertonic, hypotonic
or isotonic? Justify your answer.
7. What did the gummy bear model in this lab? Was the gummy bear a realistic model? Please justify
your response.
Part 2: Starch / Iodine Diffusion Lab
Introduction: In this lab you will observe the diffusion of a substance across a semi permeable
membrane. Iodine is a known indicator for starch. An indicator is a substance that chances color in the
presence of the substance it indicates. Watch as your teacher demonstrates how iodine changes in the
presence of starch. The purpose of this lab is to observe the movement of solutes in a concentration
gradient, in an attempt to reach equilibrium (homeostasis).
Pre-lab Observations: Describe what happened when iodine came into contact with starch.
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Experimental Procedure:
1. Fill a plastic bag with 10 grams of corn starch and a 25 ml of water then tie the bag. Obtain the
mass of the cornstarch water bag.
2. Fill a cup with 150mL of water and add 15 drops of iodine with a transfer pipette.
3. Place the bag in the cup so that the cornstarch mixture is submerged in the iodine water
mixture.
4. Wait 24 hours and record your observations in the data table. While you are waiting, record
initial observations in the data table and answer questions 1-13 below.
Pre-Lab Questions:
1. Compare and contrast the process of diffusion and osmosis.
2. The bag in this lab represents a model of a cell. How is this realistic representation?
3. Why is iodine used as an indicator (think back to Mag-Mush)?
4. Molecules that move by means of passive transport tend to move from areas of _______
concentration to areas of ______ concentration.
* We are going to think about concentrations now, which substances are more or less concentrated
depends on which one has the most substance in it.
5. Is the bag or cup more concentrated in starch?
6. Is the bag or cup more concentrated in iodine?
7. What macromolecule could starch be categorized as? What type of cell transport is required for these
types of molecules?
8. Explain the difference between passive transport and active transport. Predict which one you will be
observing?
* Make Some Predictions:
9. If the bag was permeable to starch, which way would the starch move, into the bag or out of the bag?
10. If the bag was permeable to iodine, which way would the iodine move, into or out of the bag?
11. If the bag was permeable to iodine, what color would you expect the solution in the baggie to turn?
12. If the bag was permeable to starch, what color would you expect the solution in the bag to turn?
13. Make a hypothesis about what you think will happen and justify your thoughts.
Data Table: Monitoring color change of the solutions.
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Post Lab Analysis:
1. Based on your observations, which substance moved, the iodine/water solution or the starch?
2. How did you determine this and why do you believe this occurred?
3. The plastic baggie was permeable to which substance?
4. Is the plastic baggie selectively permeable? Why, what does it mean to be selectivity permeable?
5. Sketch the cup and bag and label arrows to illustrate how diffusion occurred in this lab.
6. Explain what would happen if you did an experiment in which the iodine solution was placed in the
bag, and the starch solution was in the beaker? Be detailed in your description. You can even do the
experiment if you would like!
7. Describe the difference in color of the iodine solution initially compared to the iodine solution at the
end of the experiment?
8. Did you see a difference in the mass of the bag? Explain why or why not.
9. Explain the difference between qualitative and quantitative data, citing examples of each in this lab.
Released EOC Questions
1. Which statement is not part of the cell theory?
a. Cells are the basic unit of structure of living things.
b. Cells are the basic unit of function of living things.
c. Cell parts such as chloroplasts are self-replicating.
d. Cells come from pre-existing cells.
2. Which statement regarding the functioning of the cell membrane of all organisms is not correct/
a. The cell membrane forms a boundary that separates the cellular contents from the
outside environment.
b. The cell membrane is capable of receiving and recognizing chemical signals.
c. The cell membrane forms a barrier that keeps all substances that might harm the cell
from entering the cell.
d. The cell membrane controls the movement of materials into or out of the cell.
3. When Elodea cells (cells of a freshwater plant) are placed in a saltwater solution, the cells
undergo __________, which means the _________ of the cell.
a. Hydrolysis … bursting
b. Plasmolysis … shrinking
4. One difference between plant and animal cells is that animal cells do not have
a. A nucleus
b. A cell membrane
c. Chloroplasts
d. centrioles
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Test Review
1. What is the main difference between prokaryotic and eukaryotic cells?
2. What are two main differences between plant and animal cells?
3. Create a Venn diagram comparing and contrasting prokaryotic and eukaryotic cells. Include at
least three characteristics / cell parts in each section.
4. Describe the endosymbiotic theory, and detail the evidence that supports it.
5. Write pro’s and con’s about being a unicellular organism versus a multicellular organism.
6. What are chromosomes, and how many do humans have, and the bacteria E. Coli have?
7. Draw a plant cell and label 10 organelles (2 need to be ones not found in animal cells).
8. Draw an animal cell and label 8 organelles.
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