Question

Which of the following is NOT true for all three of these transport mechanisms: facilitated diffusion, primary active transport, and secondary active transport?

A) The transport mechanism requires a protein.

B) Transport can be increased by increasing the number of transport molecules in the plasma membrane.

C) The transport mechanism requires energy.

D) The transport mechanism is specific for (a) particular solute(s).

E) The transport mechanism has a limit to the total number of molecules that can be transported per unit of time

Answer 1

The statement that is NOT true for all transport mechanisms including facilitated diffusion, primary active transport, and secondary active transport is that the transport mechanism requires energy. Facilitated diffusion doesn't require energy, whereas active transport does.

Step-by-step explanation:

The answer to the student's question, which asks which statement is NOT true for all three transport mechanisms: facilitated diffusion, primary active transport, and secondary active transport, is option C) The transport mechanism requires energy. Facilitated diffusion does not require energy because it moves substances down their concentration gradient through specific protein channels. In contrast, primary active transport and secondary active transport both require energy. Primary active transport uses ATP directly, while secondary active transport depends on electrochemical gradients created by primary active transport.

All three mechanisms do require a protein (transporters, carriers, or pumps), can potentially increase transport by increasing the number of transport molecules in the plasma membrane, are specific for particular solutes, and have a saturation point limiting the rate at which they can transport substances.