Macronutrient & Micronutrient Science Flashcards

Which form of carbohydrate resists digestion in the small intestine and is fermented by bacteria in the large intestine?

Answer: Dietary fiber

Dietary fiber (soluble and insoluble) passes through the small intestine largely intact and is partially fermented by gut microbiota in the colon.

Which amino acid is conditionally essential during periods of rapid growth, severe illness, or injury?

Answer: Glutamine

Glutamine becomes conditionally essential under metabolic stress because demand exceeds the body's synthesis capacity, making dietary intake critical.

What is the Acceptable Macronutrient Distribution Range (AMDR) for fat as a percentage of total daily calories for adults?

Answer: 20–35%

The AMDR for fat for adults is 20–35% of total calories, balancing energy needs with cardiovascular health considerations.

Zinc is a cofactor for over 300 enzymes and is especially important for which function?

Answer: Immune function and wound healing

Zinc supports immune cell function, protein synthesis, and wound healing, making it critical during growth, illness, and tissue repair.

Which type of dietary fat has been shown to raise LDL cholesterol while also lowering HDL cholesterol, making it particularly harmful to cardiovascular health?

Answer: Trans fat

Artificial trans fats (partially hydrogenated oils) raise LDL and lower HDL simultaneously, creating a uniquely atherogenic lipid profile.

Which vitamin is essential for blood clotting and activates clotting factors by enabling gamma-carboxylation of glutamic acid residues?

Answer: Vitamin K

Vitamin K acts as a cofactor for carboxylase enzymes that activate clotting factors II, VII, IX, and X in the coagulation cascade.

Which macronutrient is the preferred and most efficient fuel source for the brain under normal dietary conditions?

Answer: Glucose

The brain relies primarily on glucose as its fuel under normal conditions, consuming approximately 120 grams per day.