Which statement about active transport is true?

• A. Active transport requires energy in the form of ATP.
• B. Active transport is a type of passive transport.
• C. Active transport occurs only in animal cells.
• D. Active transport moves substances down their concentration gradient.

Answer: (A)

Verified step by step guidance

1. Begin by understanding the concept of active transport. Active transport is a cellular process in which substances are moved across a cell membrane against their concentration gradient, meaning from an area of lower concentration to an area of higher concentration.
2. Recognize that active transport requires energy. This energy is typically provided by ATP (adenosine triphosphate), which is the energy currency of the cell. ATP is used to power the transport proteins that move substances across the membrane.
3. Differentiate between active transport and passive transport. Passive transport does not require energy and moves substances down their concentration gradient, from high to low concentration. Active transport, on the other hand, requires energy and moves substances against their concentration gradient.
4. Consider the types of cells where active transport occurs. Active transport is not limited to animal cells; it occurs in both plant and animal cells, as well as in other types of cells.
5. Evaluate the statement options given in the problem. The correct statement about active transport is that it requires energy in the form of ATP, as this is a defining characteristic of active transport.