Question

which statement is true of both active transport and facilitated diffusion?

both move materials down a concentration gradient

both occur in only one direction

both require atp

both involve proteins in the cell membrane

Explanation:

1. Analyze "Both move materials down a concentration gradient": Active transport moves materials against the concentration gradient (from low to high), while facilitated diffusion moves down (from high to low). So this is false.
2. Analyze "Both occur in only one direction": Active transport can be bidirectional in some cases, and facilitated diffusion also isn't strictly one - way. So this is false.
3. Analyze "Both require ATP": Facilitated diffusion is a passive process and does not require ATP, while active transport does. So this is false.
4. Analyze "Both involve proteins in the cell membrane": Active transport uses carrier proteins (like pumps), and facilitated diffusion uses channel or carrier proteins. So this is true.

Answer:

The correct option is: Both involve proteins in the cell membrane.