1. Learning Goal: Identify the major components of a cell membrane.

2. Which of the following is NOT a component of the cell membrane?
1. Phospholipids 2. Cholesterol 3. Nucleic acids 4. Proteins

3. Which letter is pointing to the phospholipid bilayer?
1. J 2. C 3. I 4. F

4. Which letter is pointing to a protein?
1. C 2. J 3. E 4. I

5. Which letter is pointing a cholesterol molecule?
1. B 2. D 3. A 4. I

6. What kinds of molecules are attracted to water?
1. Hydrophobic molecules 2. Hydrophilic molecules

7. Which part of the phospholipid is hydrophobic?
1. Phosphate heads 2. Fatty acid tails

8. Water is polar. The inside of the cell membrane is nonpolar
Water is polar. The inside of the cell membrane is nonpolar. How does water flow through the membrane?
Directly across the phospholipid bilayer
Through a protein channel
Through a cholesterol molecule
By attaching to carbohydrate chains

9. What is the function of channel proteins?
1. changes the fluidity of the cell membrane 2. To make center of the cell membrane hydrophobic 3. Act as an identification marker 4. To provide a pathway for certain substances to cross the cell membrane

10. What is the function of cholesterol in the cell membrane?
To make the center of the membrane hydrophilic
To make the center of the membrane hydrophobic
To maintain the fluidity of the cell membrane
To act as an identification marker for the cell

11. Blood type is determined by the structure of the cell membrane of red blood cells. What molecule within the cell membrane of red blood cells allows other cells to recognize the red blood cells as type A, B, AB, or O.
1. Phospholipids 2. Cholesterol 3. Protein pumps 4. Carbohydrate chains