Question

Which of the following amino acids are essential amino acids in humans:
A. Leucine
B. Lysine
C. Isoleucine
D. Serine
Choose the correct answer from the options given below:

• A. A, B, and C Only
• B. B, C, and D Only
• C. A, B, C and D
• D. A, C, and D Only

Hint:

A useful mnemonic to remember the nine essential amino acids is "PVT TIM HALL": Phenylalanine, Valine, Threonine, Tryptophan, Isoleucine, Methionine, Histidine, Arginine (conditionally essential), Leucine, Lysine.

Answer 1

The Correct Option is A

Step 1: Understanding Essential Amino Acids:
Essential amino acids cannot be produced by the body in sufficient amounts and must be obtained through diet. Non-essential amino acids are synthesized by the body.
Step 2: Identification of Essential Amino Acids:
The nine essential amino acids for adults are: Histidine, Isoleucine, Leucine, Lysine, Methionine, Phenylalanine, Threonine, Tryptophan, and Valine.
Classification of the given amino acids:


A. Leucine: Essential amino acid.

B. Lysine: Essential amino acid.

C. Isoleucine: Essential amino acid.

D. Serine: Non-essential amino acid; synthesized from molecules like glycine or 3-phosphoglycerate.

Step 3: Conclusion:
Leucine, Lysine, and Isoleucine (A, B, C) are essential. Serine is non-essential. Therefore, the answer includes A, B, and C.