Macro Coach Macronutrient Science Fundamentals Questions and Answers Flashcards

During prolonged caloric restriction, which process allows the liver to synthesize glucose from non-carbohydrate precursors such as amino acids and glycerol?

Answer: Gluconeogenesis

Gluconeogenesis is the metabolic pathway that produces glucose from substrates like lactate, alanine, and glycerol when dietary carbohydrates are insufficient.

Nitrogen balance is used to assess protein status. A client in positive nitrogen balance is most likely experiencing which state?

Answer: Net muscle protein synthesis

Positive nitrogen balance means nitrogen intake exceeds excretion, indicating that more protein is being built than broken down — a requirement for muscle growth.

Which enzyme is responsible for catalyzing the first committed step of fatty acid synthesis?

Answer: Acetyl-CoA carboxylase

Acetyl-CoA carboxylase converts acetyl-CoA to malonyl-CoA, committing the carbon units to the de novo lipogenesis pathway.

What is the caloric density of dietary fat per gram?

Answer: 9 kcal/g

Fat provides 9 kcal per gram, more than twice the caloric density of carbohydrates or protein, reflecting its highly reduced chemical structure.

Which digestive enzyme is secreted by the pancreas and is primarily responsible for breaking down dietary fat in the small intestine?

Answer: Pancreatic lipase

Pancreatic lipase hydrolyzes triglycerides into free fatty acids and monoglycerides at the brush border of the small intestinal lumen.

The glycemic index (GI) measures which characteristic of a carbohydrate-containing food?

Answer: Rate at which a food raises blood glucose relative to pure glucose

GI ranks foods on a 0–100 scale based on how quickly they raise blood glucose compared to a reference food (pure glucose = 100).