Question

Identify the essential amino acids from below:
(A) Valine
(B) Proline
(C) Lysine
(D) Threonine
(E) Tyrosine
Choose the correct answer from the options given below:

• A. (A), (C) and (D) only
• B. (A), (C) and (E) only
• C. (B), (C) and (E) only
• D. (C), (D) and (E) only

Hint:

Essential amino acids are those that the body cannot produce on its own, and must be acquired from food. Examples include Valine, Lysine, and Threonine.

Answer 1

The Correct Option is A

Essential amino acids are those that cannot be synthesized by the human body and must be obtained through the diet. Among the amino acids listed: 
-Valine (A) is an essential amino acid. 
- Proline (B) is a non-essential amino acid, as the body can synthesize it. 
- Lysine (C) is an essential amino acid. 
- Threonine (D) is an essential amino acid. 
- Tyrosine (E) is a non-essential amino acid because it can be synthesized from phenylalanine, which is essential. 
Thus, the essential amino acids are Valine, Lysine, and Threonine, making the correct answer (1).

Answer 2

Step 1: Understand the question.
We are asked to identify the essential amino acids from the given list:
(A) Valine
(B) Proline
(C) Lysine
(D) Threonine
(E) Tyrosine

Step 2: Recall the definition of essential amino acids.
Essential amino acids are those that cannot be synthesized by the human body and must be obtained through diet. There are nine essential amino acids in total — Valine, Leucine, Isoleucine, Lysine, Methionine, Phenylalanine, Threonine, Tryptophan, and Histidine.

Step 3: Analyze each amino acid given.
(A) Valine – Essential amino acid.
(B) Proline – Non-essential amino acid (it can be synthesized by the body).
(C) Lysine – Essential amino acid.
(D) Threonine – Essential amino acid.
(E) Tyrosine – Non-essential amino acid (derived from phenylalanine).

Step 4: Identify the essential ones.
Essential amino acids from the list are: (A) Valine, (C) Lysine, and (D) Threonine.

Final Answer:
(A), (C), and (D) only.
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