BIOL 100L Laboratory Module 4 Cell Membrane, Diffusion and Osmosis Name Date Section 1: Objective – What do you think is the objective of section
BIOL 100L
Laboratory Module 4
Cell Membrane, Diffusion and Osmosis
Name Date
Section 1:
Objective – What do you think is the objective of section 1 of this laboratory module? Write the objective in bullet form bellow. (2 points)
· Objective
Answer the following questions. (10 points)
1. What molecule forms the basic framework of the cell membrane?
2. Which part of the molecule in question 1 is Hydrophilic?
3. Which part of the molecule in question 1 is Hydrophobic?
4. What is the function of the Glycoprotein molecule in the cell membrane?
5. What molecules are found in the animal cell membranes but not in the plant cell membranes?
Section 2:
Objectives – What do you think is the objective of section2 of this laboratory module? Write the objectives in bullet form bellow. (4 points)
· Objective 1.
· Objective 2.
Activity A. Answer the following questions after completing the diffusion tutorial. (15 points)
1. What is a concentration gradient?
2. What is diffusion?
3. If the same amount of particles move from side A to B as they move from Side B to A, have we reached equilibrium? Answer True or False and explain why.
4. What happens in the animation when the temperature is raised?
5. What happens in the animation when the temperature is lowered?
6. What effect do you think would rising or lowering the temperature will have in the rate (the speed at which a reaction occurs) of diffusion?
Activity B. Document your experiment with pictures and answer the following questions. (20 points)
1. What was your Hypothesis before you started the experiment? Note: A hypothesis is an educated guess. To create your hypothesis answer the question - Based on what I know how would I predict the experiment will come out?
2. What was the rate of diffusion of tea in cold water?
3. What was the rate of diffusion of tea in hot water?
4. Compare both rates of diffusion. Which was faster?
5. Do your results agree with your hypothesis?
6. Try to explain the results of your experiment based on the things you learned in the diffusion tutorial.
Do an internet search and find a website that talks about how diffusion affects a particular function in the human body. (5 points)
Section 3:
Objectives – What do you think is the objective of section 3 of this laboratory module? Write the objectives in bullet form bellow. (4 points)
· Objective 1.
· Objective 2.
Activity C. Answer the following questions after completing the osmosis tutorial. (10 points)
1. What is Osmosis?
2. What is the main difference between Osmosis and Diffusion?
3. In the example of the cells and the blood vessel given in the tutorial, which way do you expect the water to move?
4. A marine fish has about 1% salt in his body. The ocean water is 3.5%. Will water move into or out of the fish?
5. A freshwater fish has about 1% salt in his body. Freshwater is close to 0% salt. Will water move into or out of the fish?
Find a Youtube video that explains the concepts of diffusion and osmosis. Describe the video in a couple of sentences and include the URL (internet address) of the video. (5 points)
Activity D. After completing the experiment record your results by answering the following questions. Remember to include pictures. (20 points)
1. How much salt did you put in the salt water solution?
2. What happened to the potato that was left in tap water?
3. What happened to the potato that was left in salted water?
4. Use what you have learned about Osmosis to explain your results.
5. If instead of salt you had used sugar, do you expect to obtain similar results? Explain your answer.
Do an internet search and find a website that talks about how osmosis affects a particular function in the human body. (5 points)
