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: D

Rationale: The correct answer is D, peptide bond. A peptide bond is formed through a dehydration synthesis reaction between the amine group of one amino acid and the carboxyl group of another amino acid. This bond is crucial in protein synthesis. Choices A, B, and C are incorrect. A double bond involves sharing two pairs of electrons, a hydrogen bond is a weak attraction between a hydrogen atom and an electronegative atom, and a carboxyl bond is not a common term in biochemistry.

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: 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: C

Rationale: Chylomicrons are the lipoproteins responsible for transporting dietary fat from the intestines to various tissues, including the liver. VLDL carries lipids synthesized in the liver, LDL transports cholesterol to tissues, and HDL helps transport cholesterol away from tissues to the liver for excretion. Therefore, in the context of carrying fat from a meal just consumed to the liver, chylomicrons are the correct choice.