Which statement best distinguishes plants and animals as they relate to amino acids?

• A. Animals require certain essential amino acids in their diet because they cannot synthesize all of them, whereas plants can synthesize all amino acids they need.
• B. Both plants and animals can synthesize all amino acids required for protein synthesis.
• C. Neither plants nor animals can synthesize any amino acids; both must obtain all amino acids from their diet.
• D. Plants require essential amino acids from their environment, while animals can synthesize all amino acids.

Answer: (A)

Verified step by step guidance

1. Step 1: Begin by understanding the concept of amino acids. Amino acids are the building blocks of proteins, and organisms use them to synthesize proteins necessary for various biological functions.
2. Step 2: Recognize the difference between essential and non-essential amino acids. Essential amino acids cannot be synthesized by an organism and must be obtained from the diet, while non-essential amino acids can be synthesized by the organism itself.
3. Step 3: Analyze the metabolic capabilities of plants and animals. Plants have the ability to synthesize all amino acids they need, including essential ones, using inorganic nitrogen sources from their environment. Animals, on the other hand, lack the ability to synthesize certain essential amino acids and must obtain them through their diet.
4. Step 4: Evaluate the statements provided in the problem. Compare each statement to the biological facts about amino acid synthesis in plants and animals to determine which one aligns with scientific understanding.
5. Step 5: Identify the correct statement based on the analysis. The correct answer is: 'Animals require certain essential amino acids in their diet because they cannot synthesize all of them, whereas plants can synthesize all amino acids they need.' This statement accurately reflects the distinction between plants and animals regarding amino acid synthesis.