Modified from Pedersen
AP BIOLOGY
Unit 2 – Cells and Cell Communication
Bozeman videos (#’s 43, 15, 16, 36-39) due Monday 12/1 – NO
EXCEPTIONS OR EXCUSES!
PRELAB ACTIVITEES – DUE MONDAY 11/21
1. Osmosis and Diffusion Pre-Lab Bozeman Videos – Beneficial but optional
a. 01 Lab – Diffusion & Osmosis
b. Osmosis lab Walkthrough – good for potato coring procedure
c. Diffusion Demo
2. Pearson LabBench Activity – Diffusion and Osmosis
http://www.phschool.com/science/biology_place/labbench/lab1/intro.html
Complete the following questions as you work your way through the online lab for osmosis and diffusion. This portion is
due Friday 11/21 – NO EXCEPTIONS OR EXCUSES!
1. When you take a closer look at the 0.2M baggie in the 0.8M solution, which direction did the water move?
2. When you take a closer look at the concentration gradient animation, which molecules are able to cross the
selectively permeable membrane?
3. Explain how a solution is hypertonic or hypotonic based on the solute concentrations?
4. Explain the concept of water potential.
5. How does the response of an animal cell and a plant cell differ in response to being placed in distilled water?
6. Write the water potential equation and label the variables.
7. In your own words, explain why a solution with a molarity of 0.2 can be in equilibrium with a solution with a
molarity of 0.4.
8. Exercise 3, 4 and 5 will be beneficial in designing and understanding your own lab investigation.
9. Complete the sample problems in the “Analysis of Results” section. Show all work below. If you calculated it
incorrectly then explain the correct answer after you check your answer.
Bozeman Videos that correlate with Chapters 6, 7 and 11
Complete the following notes for each video.
The video questions need to be completed by Monday 12/1 – NO EXCEPTIONS OR EXCUSES!
Bozeman video #43 Cellular Organelles corresponds with Chapter 6: A Tour of the Cell.
1. What are the two main roles of the nucleus?
2. How are the ribosomes and rough ER connected in terms of their function (not the fact that the rough
ER is rough because it has ribosomes on it)?
3. What are two roles of the smooth ER?
4. What are the two parts of a ribosome? Where are ribosomes synthesized?
5. What two locations in the cell can ribosomes make proteins?
6. What analogy is applied in the video to the rough ER?
7. What is the function of the golgi within a cell? What common analogy is given to the golgi?
Modified from Pedersen
8. Lysosome contain digestive enzymes that allow it to:
a. –
b. –
c. –
9. Where do the enzymes in the lysosomes originate?
10. Why is the inner membrane of the mitochondria folded?
11. What can a vacuole store?
12. Why are the stacks of thylakoids (grana) designed to have a high surface area?
Questions you have?
Bozeman video #15 Cell Membranes and #16 Transport across Cell Membranes corresponds with Chapter 7:
Membrane Structure and Function.
Bozeman video # 15 – Cell Membranes
1. Describe the fluid mosaic model.
2. What are the roles of the following molecules within the cell membrane:
a. Cholesterol
b. Glycoprotein
c. Glycolipid
3. Explain the difference in structure and charge between most lipids and phospholipids.
4. What two factors allow CO2 and O2 to easily and freely move across the phospholipid bilayer?
5. What is the essential role of proteins that are embedded in the cell membrane?
6. What is the role of an aquaporin?
7. The sodium/potassium pump is also a ________________.
8. What is the role of the cell wall and what is it composed of?
9. What part of a bacterial cell is targeted by many antibiotics? What is this part composed of?
10. What is a fungal cell wall composed of?
Questions you have?
Bozeman video #16 – Transport across Cell Membranes
1. Osmosis is the result of water movement across the cell membrane from an area of H concentration to L
concentration. Using the example of the “sugar water and less sugar water”, explain when water will “stop” its
movement across the membrane.
2. Define hypertonic
3. Define hypotonic
4. Explain how glucose crosses the cell membrane?
5. When is co-transport used?
6. ATP is used for active transport, as seen in the Na/K pump. This pump moves molecules against their
concentration gradient. This pump moves three sodium ions ________________ the cell and two potassium
ions_______________ the cell.
7. What type of cell is a phagocyte?
8. Explain the relationship between a phagosome and a lysosome.
Modified from Pedersen
Questions you have?
Bozeman videos #36-39 corresponds with Chapter 11: Cell Communication.
Video #36 – Evolution of Cell Communication
1. How is cell communication different between multicellular organisms and single-celled organisms?
2. Do the similarities in signal transduction pathways for both prokaryotes and eukaryotes support the theory of
evolution?
3. Summarize how quorum sensing works in Vibrio fisheri works.
4. What is a possible constraint that a multicellular eukaryote faces with regards to cell communication?
5. Summarize the signal transduction pathway once epinephrine is produced by the adrenal gland.
Questions you have?
Video #37 – Cell Communication
1. Summarize the direct communication that occurs within an organism to produce antibodies once exposed to a
virus.
2. Summarize how messages travel within an organism when there is a distance between two cells using the
example of neurtransmitters.
3. What are some possible reasons that scientists believe there is a distance between neurons?
4. How do beta-endorphins relieve pain?
5. What are possible results of increasing the amount of growth hormone produced on the different cells that
receive the hormone?
6. What type of cell communication correspond to the following analogies:
a. Post-it
b. Email
c. Facebook
Questions you have?
Video #38 – Signal Transduction Pathways
1. What analogy is given for signal transduction pathways?
2. What are two results of a signal transduction pathway action?
3. Summarize what happens to the liver when a messenger such as epinephrine is given off by the adrenal gland.
Use key terms such as: G-protein, ligand, protein, ATP, cAMP, protein kinase, phosphorylation, glucose, etc.
4. Create your own analogy for signal transduction pathways.
Questions you have?
Video #39 – Effects of Changes in Pathways
1. What part of the cell does tetrodotoxin, which is found in the California Newt, negatively impact?
2. Complete the flow chart below as a review for signal transduction pathways:
Messenger ______________  ____________  ______________ Cell Targets
Modified from Pedersen
3. Describe the disruption that occurs within the signal transduction pathway for the following examples:
a. Anthrax
b. Diabetes
Questions you have?