Macronutrient & Micronutrient Science Flashcards

Which fatty acid is classified as an omega-3 and must be obtained through diet because the human body cannot synthesize it?

Answer: Alpha-linolenic acid (ALA)

ALA is an essential omega-3 fatty acid that humans cannot synthesize and must consume through foods like flaxseed, chia seeds, and walnuts.

A client who avoids all animal products is at highest risk for deficiency in which micronutrient?

Answer: Vitamin B12

Vitamin B12 is found almost exclusively in animal-derived foods, making vegans highly susceptible to deficiency without supplementation.

During carbohydrate digestion, which enzyme in saliva begins breaking down starch into shorter polysaccharides?

Answer: Amylase

Salivary amylase (ptyalin) initiates starch digestion in the mouth by cleaving alpha-1,4-glycosidic bonds.

Which mineral is a central component of the hemoglobin molecule and is critical for oxygen transport?

Answer: Iron

Iron is the mineral at the core of heme in hemoglobin, enabling red blood cells to bind and transport oxygen throughout the body.

Which macronutrient yields approximately 9 kilocalories per gram, the highest of all macronutrients?

Answer: Fat

Dietary fat provides 9 kcal/g, more than double the 4 kcal/g provided by carbohydrates and protein.

Scurvy results from a deficiency of which vitamin, impairing collagen synthesis?

Answer: Vitamin C

Vitamin C (ascorbic acid) is required as a cofactor for enzymes that hydroxylate proline and lysine residues during collagen formation.

What term describes amino acids that the body can synthesize on its own and do not need to be obtained from food?

Answer: Non-essential amino acids

Non-essential amino acids can be synthesized endogenously from other metabolic precursors, so they are not required in the diet.