Proteins from plant sources such as grains, nuts, and legumes are classified as:

Correct Answer: A

Rationale: The correct answer is A: 'incomplete.' Proteins from plant sources like grains, nuts, and legumes are considered incomplete because they often lack one or more essential amino acids required by the body. Choice B, 'complete,' is incorrect because complete proteins contain all essential amino acids in adequate amounts. Choice C, 'indispensable,' is incorrect as it refers to essential amino acids rather than the classification of plant proteins. Choice D, 'dispensable,' is also incorrect as it implies that these proteins are not necessary, which is not the case.

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: 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: Bile salts are essential for emulsifying fats in the body. They break down fats into smaller droplets, increasing the surface area for enzymes to work on during digestion. Cholecystokinin is a hormone that stimulates the release of bile and pancreatic enzymes, but it is not directly involved in emulsification. Chyme is the semi-fluid mass of partly digested food that moves from the stomach to the small intestine and does not play a role in emulsifying fats. Trypsin is an enzyme produced by the pancreas that acts on proteins, not fats.

Correct Answer: B

Rationale: Hemoglobin is a protein that carries oxygen in the blood, making it the correct answer. Choice A, Saline, is a salt solution and not a protein. Choice C, Cellulose, is a complex carbohydrate found in the cell walls of plants, not a protein. Choice D, Prostaglandins, are lipid compounds with hormone-like effects, not proteins.

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: B

Rationale: The correct answer is B, 'dispensable.' Dispensable amino acids are those that the body can synthesize in sufficient amounts, so they are not required to be obtained from the diet. Indispensable amino acids, on the other hand, are essential and must be obtained from the diet because the body cannot produce them in sufficient quantities. Choices C and D, 'simple' and 'complex,' are incorrect as they do not accurately describe amino acids in terms of synthesis by the body.

Correct Answer: B

Rationale: The correct answer is B: Plant sterols. Plant sterols can reduce cholesterol absorption by competing with cholesterol for absorption sites. Vitamin K, choice A, does not have a significant impact on cholesterol absorption. Trans fats, choice C, are known to increase cholesterol levels rather than decrease absorption. Phospholipids, choice D, play a role in cell structure and are not directly involved in reducing cholesterol absorption.

Correct Answer: C

Rationale: The correct answer is C: amino acids. Proteins are broken down by digestive enzymes into amino acids before being absorbed in the small intestine. Amino acids are the building blocks of proteins and are the form in which they are primarily absorbed. Choice A (fatty acids) is incorrect as fatty acids are the end products of fat digestion, not protein digestion. Choice B (disaccharides) is incorrect because disaccharides are sugars that are broken down into monosaccharides, not proteins. Choice D (polypeptides) is incorrect as proteins are broken down into amino acids and not absorbed as polypeptides.