Practice Questions for Carbohydrates and Proteins Structure, Types, and Functions PDF

**Practice questions for Carbohydrates and Proteins structure, types and functions:** **Carbohydrates:** 1. Which of the following is a monosaccharide? - a\) Sucrose - b\) Lactose - c\) Fructose - d\) Glycogen\ Answer: c) Fructose 2. Which is the most common...

**Practice questions for Carbohydrates and Proteins structure, types and functions:** **Carbohydrates:** 1. Which of the following is a monosaccharide? - a\) Sucrose - b\) Lactose - c\) Fructose - d\) Glycogen\ Answer: c) Fructose 2. Which is the most common disaccharide found in milk? - a\) Sucrose - b\) Lactose - c\) Maltose - d\) Glucose\ Answer: b) Lactose 3. What type of bond links monosaccharides to form disaccharides? - a\) Phosphodiester bond - b\) Hydrogen bond - c\) Glycosidic bond - d\) Peptide bond\ Answer: c) Glycosidic bond 4. Starch is composed of which two polysaccharides? - a\) Cellulose and glycogen - b\) Amylose and amylopectin - c\) Maltose and glucose - d\) Fructose and galactose\ Answer: b) Amylose and amylopectin 5. Which of the following is an example of a storage carbohydrate in animals? - a\) Cellulose - b\) Glycogen - c\) Starch - d\) Chitin\ Answer: b) Glycogen 6. The major structural carbohydrate in plants is: - a\) Chitin - b\) Glycogen - c\) Cellulose - d\) Amylopectin\ Answer: c) Cellulose 7. Which of the following is a reducing sugar? - a\) Sucrose - b\) Glucose - c\) Cellulose\ Answer: b) Glucose 8. Which enzyme breaks down starch into maltose? - a\) Amylase - b\) Lactase - c\) Sucrase - d\) Glucokinase\ Answer: a) Amylase 9. Which monosaccharide is an aldose? - a\) Fructose - b\) Glucose - c\) Ribulose\ Answer: b) Glucose 10. Chitin is a polysaccharide found in: - a\) Fungi cell walls - b\) Animal muscle cells - c\) Human liver - d\) Plant cell walls\ Answer: a) Fungi cell walls 11. The main function of glycogen is: - a\) Structural support in plants - b\) Energy storage in animals - c\) Water retention - d\) Transporting glucose in the blood\ Answer: b) Energy storage in animals 12. Which of the following is a pentose sugar? - a\) Glucose - b\) Fructose - c\) Ribose - d\) Galactose\ Answer: c) Ribose 13. Which carbohydrate cannot be digested by humans? - a\) Starch - b\) Glycogen - c\) Cellulose - d\) Sucrose\ Answer: c) Cellulose 14. Which of the following polysaccharides is highly branched? - a\) Amylose - b\) Glycogen - c\) Cellulose - d\) Chitin\ Answer: b) Glycogen 15. Lactose is composed of which two monosaccharides? - a\) Glucose and fructose - b\) Glucose and galactose - c\) Glucose and glucose - d\) Glucose and mannose\ Answer: b) Glucose and galactose 16. The primary role of carbohydrates in the body is to: - a\) Act as enzymes - b\) Provide structural support - c\) Store genetic information - d\) Provide energy\ Answer: d) Provide energy 17. Which sugar is the main form of carbohydrate found in blood? - a\) Fructose - b\) Glucose - c\) Lactose - d\) Sucrose\ Answer: b) Glucose 18. Which of the following is a component of bacterial cell walls? - a\) Peptidoglycan - b\) Chitin - c\) Starch - d\) Glycogen\ Answer: a) Peptidoglycan 19. Which is the major carbohydrate used for energy in plants? - a\) Cellulose - b\) Starch - c\) Glycogen - d\) Sucrose\ Answer: b) Starch 20. Sucrose is a disaccharide composed of: - a\) Glucose and galactose - b\) Glucose and fructose - c\) Glucose and glucose - d\) Glucose and ribose\ Answer: b) Glucose and fructose **Proteins:** 21. What type of bond connects amino acids in proteins? - a\) Glycosidic bond - b\) Peptide bond - c\) Phosphodiester bond - d\) Hydrogen bond\ Answer: b) Peptide bond 22. Which of the following is an essential amino acid? - a\) Glutamine - b\) Lysine - c\) Glycine - d\) Serine\ Answer: b) Lysine 23. What is the primary structure of a protein? - a\) The sequence of amino acids - b\) The folding of polypeptide chains - c\) The interaction between multiple polypeptide chains - d\) The 3D shape of a protein\ Answer: a) The sequence of amino acids 24. Hemoglobin is an example of a protein with: - a\) Primary structure only - b\) Tertiary structure - c\) Quaternary structure - d\) No secondary structure\ Answer: c) Quaternary structure 25. Which of the following stabilizes the secondary structure of proteins? - a\) Hydrogen bonds - b\) Disulfide bonds - c\) Ionic bonds - d\) Hydrophobic interactions\ Answer: a) Hydrogen bonds 26. Which protein is responsible for oxygen transport in blood? - a\) Myosin - b\) Hemoglobin - c\) Collagen - d\) Insulin\ Answer: b) Hemoglobin 27. The tertiary structure of a protein is primarily determined by: - a\) Hydrogen bonding - b\) The linear sequence of amino acids - c\) Interactions between side chains (R groups) - d\) Phosphorylation\ Answer: c) Interactions between side chains (R groups) 28. What is the role of enzymes in the body? - a\) To store genetic information - b\) To catalyze biochemical reactions - c\) To provide structural support - d\) To transport molecules across membranes\ Answer: b) To catalyze biochemical reactions 29. Which of the following is a fibrous protein? - a\) Hemoglobin - b\) Insulin - c\) Collagen - d\) Amylase\ Answer: c) Collagen 30. Proteins are synthesized by: - a\) The Golgi apparatus - b\) Ribosomes - c\) Lysosomes - d\) Mitochondria\ Answer: b) Ribosomes 31. Which of the following amino acids contains sulfur? - a\) Methionine - b\) Glycine - c\) Leucine - d\) Glutamine\ Answer: a) Methionine 32. A denatured protein has lost its: - a\) Primary structure - b\) Quaternary structure - c\) Tertiary structure - d\) Covalent bonds\ Answer: c) Tertiary structure 33. What type of interaction is primarily responsible for stabilizing alpha-helices in proteins? - a\) Hydrogen bonds - b\) Ionic bonds - c\) Covalent bonds - d\) Van der Waals interactions\ Answer: a) Hydrogen bonds 34. Which protein is primarily involved in muscle contraction? - a\) Actin - b\) Myoglobin - c\) Hemoglobin - d\) Collagen\ Answer: a) Actin 35. Which of the following is not a function of proteins? - a\) Structural support - b\) Catalyzing reactions - c\) Storing genetic information - d\) Transporting molecules\ Answer: c) Storing genetic information 36. Which bond forms between the carboxyl group of one amino acid and the amino group of another? - a\) Hydrogen bond - b\) Peptide bond - c\) Ionic bond - d\) Covalent bond\ Answer: b) Peptide bond 37. Which level of protein structure involves multiple polypeptide chains? - a\) Primary - b\) Secondary - c\) Tertiary - d\) Quaternary\ Answer: d) Quaternary 38. Which protein is found in high concentrations in hair, nails, and skin? - a\) Collagen - b\) Keratin - c\) Actin - d\) Elastin\ Answer: b) Keratin 39. Which process describes the formation of a peptide bond between amino acids? - a\) Hydrolysis - b\) Condensation - c\) Phosphorylation - d\) Glycosylation\ Answer: b) Condensation 40. A protein's function is most directly determined by its: - a\) Size - b\) pH - c\) 3D shape - d\) Amino acid content\ Answer: c) 3D shape 41. The R group of an amino acid determines its: - a\) Charge - b\) Solubility - c\) Interaction with other molecules - d\) All of the above\ Answer: d) All of the above 42. What kind of protein structure do beta-sheets represent? - a\) Primary - b\) Secondary - c\) Tertiary - d\) Quaternary\ Answer: b) Secondary 43. Which protein is involved in blood clotting? - a\) Fibrinogen - b\) Collagen - c\) Myosin - d\) Hemoglobin\ Answer: a) Fibrinogen 44. Denaturation of a protein affects its: - a\) Primary structure - b\) Secondary and tertiary structures - c\) Amino acid sequence - d\) Peptide bonds\ Answer: b) Secondary and tertiary structures 45. Which molecule is commonly known as the energy currency of the cell? - a\) Glucose - b\) ATP - c\) NADH - d\) DNA\ Answer: b) ATP 46. Amino acids that cannot be synthesized by the human body are called: - a\) Essential amino acids - b\) Non-essential amino acids - c\) Branched-chain amino acids - d\) Aromatic amino acids\ Answer: a) Essential amino acids 47. What is the main structural protein in the extracellular matrix of animal tissues? - a\) Hemoglobin - b\) Collagen - c\) Actin - d\) Elastin\ Answer: b) Collagen 48. Which enzyme is responsible for breaking down proteins during digestion? - a\) Amylase - b\) Pepsin - c\) Lipase - d\) Maltase\ Answer: b) Pepsin