Membranes

Click on the links below to find the answer to each of these questions.

1. Describe the structure of a phospholipid molecule. [answer]
2. Draw a phospholipid bilayer and label the hydrophobic (nonpolar) and hydrophilic (polar) regions. Show where proteins are located. [answer]
3. Define and describe the following: diffusion, osmosis.
4. Explain why membranes are relatively impermeable to water-soluble molecules. [answer]
5. Explain what will happen to a red blood cell that is placed in each of the following kinds of solutions: isotonic, hypertonic, hypotonic.
6. Describe facilitated diffusion and active transport.
7. Tell whether the carrier proteins used in active transport are carbohydrate, lipid, protein, or nucleic acid. [answer]
8. Define and describe endocytosis and exocytosis.
9. Name the functions of proteins in a plasma membrane. [answer]