Question

which statement best distinguishes plants and animals as they relate to amino acids?
○ plants can synthesize all twenty amino acids. humans must eat plants or animals to obtain some of these amino acids.
○ plants can synthesize all twenty amino acids. humans must eat plants to obtain all of these amino acids.
○ plants can only synthesize ten amino acids. humans synthesize the other ten amino acids.
○ plants and humans both synthesize all twenty amino acids. humans must supplement a few of these by eating animals.

Explanation:

To solve this, we analyze each option:

• Option 1: Plants can synthesize all 20 amino acids. Humans (animals) can't synthesize all; they need to consume plants or animals for some (essential amino acids). This matches biological knowledge.
• Option 2: Humans don't need to only eat plants; they can also get amino acids from animals. So this is incorrect.
• Option 3: Plants can synthesize all 20, and humans can't synthesize all 20 (they have essential amino acids they can't make). So this is wrong.
• Option 4: Humans can't synthesize all 20 amino acids, so this is incorrect.

Answer:

A. Plants can synthesize all twenty amino acids. Humans must eat plants or animals to obtain some of these amino acids.