What is the movement of molecules across the cell membrane called when this movement does NOT need any energy to take place?
A. Passive transport
B. Hypertonic
C. ATP
D. Active transport
A. Passive transport
The movement of molecules across the cell membrane when it does NOT require any energy is called passive transport. Therefore, the correct answer is A. Passive transport.
The correct answer is A. Passive transport. Passive transport is the movement of molecules across the cell membrane that does not require any energy. It occurs spontaneously, driven by natural physical processes such as diffusion or osmosis.
To arrive at this answer, you can use your understanding of the concepts involved. In this case, you need to recall that passive transport is the process by which substances move across the cell membrane without requiring the input of energy. This contrasts with active transport, which does require energy. By eliminating the options B (Hypertonic) and C (ATP) because they do not specifically refer to the movement of molecules across the cell membrane, and by understanding that D (Active transport) involves the need for energy, you can conclude that the correct answer is A (Passive transport).