Which of the following monosaccharides is considered one of the most important in human nutrition along with glucose and fructose?

Correct Answer: B

Rationale: The most important monosaccharides in human nutrition are glucose, fructose, and galactose. Galactose is crucial as it is one of the main components of lactose, a disaccharide sugar found in milk. Therefore, choices A, C, and D are incorrect as lactose, maltose, and sucrose are disaccharides composed of two monosaccharide units.

Correct Answer: B

Rationale: Cholecystokinin (CCK) is the correct answer. It is the hormone responsible for stimulating the gallbladder to contract and release bile to aid in fat digestion. Gastric lipase (Choice A) is an enzyme that breaks down fats in the stomach, not a hormone involved in gallbladder function. Vitamin D (Choice C) is important for calcium absorption and bone health, but it is not directly related to gallbladder function. Enterokinin (Choice D) is a peptide hormone that affects smooth muscle contractions in the gastrointestinal tract, but it is not specifically responsible for stimulating the gallbladder to release bile.

Correct Answer: C

Rationale: Sucrose is the correct answer as it is the most common disaccharide found in the diet, commonly known as table sugar. Lactose is a disaccharide found in dairy products, not as prevalent in the overall diet as sucrose. Fructose is a monosaccharide commonly found in fruits and honey, not a disaccharide. Galactose is a monosaccharide commonly found in dairy products and is not the most prevalent dietary disaccharide.

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: The correct answer is A: Forming neurotransmitters. Methionine, tyrosine, and tryptophan are important amino acids involved in the production of neurotransmitters in the body. Neurotransmitters are chemical messengers that transmit signals across nerve cells, influencing various functions such as mood, memory, and muscle control. Choices B, C, and D are incorrect because these amino acids do not primarily play a role in blocking protein breakdown, increasing insulin and thyroxine production, or decreasing energy expenditure.

Correct Answer: D

Rationale: The correct answer is D: By enterokinase. Trypsin is activated by enterokinase, an enzyme secreted by the small intestine. Enterokinase plays a crucial role in converting trypsinogen into its active form, trypsin. Choices A, B, and C are incorrect because trypsin is specifically activated by enterokinase, not by zymogen, bile, or gastrin.

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: The correct answer is B, a peanut butter sandwich. A peanut butter sandwich combines grains from the bread and proteins from the nuts in the peanut butter, providing complementary proteins. This combination offers all essential amino acids. Choices A, C, and D do not contain complementary proteins as they lack the combination of different protein sources necessary to provide a complete amino acid profile.

Correct Answer: C

Rationale: The correct answer is C: 300 mg. The recommended maximum daily intake of cholesterol is 300 mg to reduce the risk of heart disease. Option A (100 mg) is too low, which may not provide enough cholesterol for normal bodily functions. Option B (200 mg) is also below the recommended limit. Option D (400 mg) exceeds the recommended daily intake, increasing the risk of heart disease.