Chapter 8, Problem 8.3PS

Mechanisms of Transport. For each of the following statements, answer with a D if the statement is true of simple diffusion, with an F if it is true of facilitated diffusion, and with an A if it is true of active transport. Any, all, or none (N) of the choices may be appropriate for a given statement.

1. (a) Requires the presence of an integral membrane protein
2. (b) Depends primarily on solubility properties of the solute
3. (c) Doubling the concentration gradient of the molecule to be transported will double the rate of transport over a broad range of concentrations.
4. (d) Involves proteins called ATPases
5. (e) Work is done during the transport process.
6. (f) Applies only to small, nonpolar solutes
7. (g) Applies only to ions
8. (h) Transport can occur in either direction across the membrane, depending on the prevailing concentration gradient.
9. (i) ΔG° = 0
10. (j) A Michaelis constant (K_m) can be calculated.