Correct Answer: A

Rationale: The correct answer is A: act as buffers. Amino acids can act as buffers by helping to maintain the pH balance in the body. Choice B is incorrect because amino acids do not primarily facilitate glucose storage. Choice C is incorrect as amino acids do not regulate the heartbeat. Choice D is also incorrect because amino acids do not control the level of blood cholesterol.

Correct Answer: A

Rationale: Oligosaccharides are carbohydrates composed of 3 to 10 monosaccharide units, making choice A the correct answer. Choice B is incorrect as oligosaccharides do not contain partially digested starch. Choice C is incorrect as nonnutritive sweeteners are a different category of compounds. Choice D is incorrect as oligosaccharides are not primarily used for weight management.

Correct Answer: B

Rationale: Most fat replacers are made from carbohydrates. Carbohydrates are utilized to mimic the texture of fats in food products. Proteins (Choice A) are not commonly used as fat replacers and are more often associated with other functions in food. Cholesterol (Choice C) is a type of fat and not used to replace fat in food products. Monoglycerides (Choice D) are sometimes used as emulsifiers or stabilizers in food products but are not the primary source of fat replacers.

Correct Answer: D

Rationale: The correct answer is glycogen. Glycogen is a type of carbohydrate stored in the body that is broken down into glucose to help maintain blood glucose levels during fasting periods. Glucose (choice A) is the simplest form of sugar and is a product of carbohydrate digestion, not the stored form like glycogen. Galactose (choice B) is a monosaccharide found in dairy products. Dextrins (choice C) are intermediate products of starch digestion and not directly involved in maintaining blood glucose levels during fasting.

Correct Answer: A

Rationale: Albumin is the correct answer. It is a plasma protein that helps maintain osmotic pressure, thereby playing a vital role in regulating fluid balance in the body. Fibrinogen is involved in blood clotting, not fluid balance. Hemoglobin is responsible for oxygen transport in red blood cells, not fluid balance. Collagen is a structural protein found in connective tissues, not directly involved in fluid balance.