Question

Select the true statements.
Chemical elements from sugars can be used to make amino acids.
Cells combine amino acids to make new proteins.
All amino acids must be consumed in foods.
Essential amino acids are made in human body cells.

Answer 1

True: 1 and 2.
False: 3 and 4.

Brief explanations:
- 1 true — cells can use carbon atoms (and energy) from sugars to build the carbon skeletons of amino acids.
- 2 true — ribosomes (and cellular machinery) join amino acids into polypeptides (proteins).
- 3 false — only essential amino acids must come from food; others are synthesized by the body.
- 4 false — by definition essential amino acids cannot be made by human cells and must be obtained from the diet.