Biochemistry explores the chemical processes within and related to living organisms. For beginners keen on understanding this intriguing branch of biology, here are 25 multiple-choice questions to test your knowledge. Each question is followed by the correct answer and an explanation to help deepen your understanding.
1. What is the primary function of carbohydrates in the body?
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Explanation:
Carbohydrates are the body’s main source of energy. They are broken down into glucose (sugar) before being used by cells.
2. Which of the following is a building block of proteins?
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Proteins are made of amino acids, which are their basic building blocks.
3. What are enzymes?
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Enzymes are proteins that act as biological catalysts to speed up chemical reactions in the body.
4. Which of the following is a nucleotide composed of?
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Nucleotides consist of a sugar, a phosphate group, and a nitrogenous base. They are the building blocks of nucleic acids.
5. What is the function of lipids in the body?
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Lipids, such as fats, serve as energy stores and insulators in the body. They also play a role in building cell membranes.
6. Which part of the amino acid can vary among different amino acids?
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The R group or side chain can vary among different amino acids, determining the differences in their properties.
7. Which biochemical process involves the synthesis of large molecules from smaller ones?
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Anabolism is the process in metabolism that builds larger molecules from smaller ones. It's the opposite of catabolism, which breaks down large molecules.
8. Which base pairs with Adenine in DNA?
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In DNA, Adenine (A) forms base pairs with Thymine (T) through two hydrogen bonds.
9. What is the primary role of RNA?
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The primary role of RNA is to act as a messenger carrying instructions from DNA for controlling the synthesis of proteins.
10. Which vitamin acts as an antioxidant?
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Vitamin C acts as an antioxidant, protecting cells from damage caused by free radicals.
11. What is the main source of energy for brain cells?
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Glucose is the primary source of energy for brain cells. The brain depends on a constant supply of glucose from the blood.
12. What is the function of hemoglobin?
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Hemoglobin is a protein in red blood cells that transports oxygen from the lungs to the rest of the body.
13. Which enzyme is responsible for breaking down lactose?
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Lactase is the enzyme that breaks down lactose, the sugar found in milk, into glucose and galactose.
14. Which hormone regulates blood sugar levels?
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Insulin is a hormone that regulates blood sugar levels by facilitating the uptake of glucose into cells.
15. What is the chemical formula of water?
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The chemical formula of water is H2O, indicating it contains two hydrogen atoms and one oxygen atom.
16. What is the primary function of the mitochondria?
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The mitochondria are the powerhouse of the cell, responsible for producing energy in the form of ATP.
17. What is the pH of a neutral solution?
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A solution with a pH of 7 is considered neutral, neither acidic nor basic.
18. What element is present in all organic compounds?
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Carbon is the fundamental element in all organic compounds, forming the backbone of organic molecules.
19. Which process breaks down glucose to produce ATP?
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Glycolysis is the metabolic pathway that converts glucose into pyruvate, releasing energy used to form ATP.
20. What is the role of ribosomes in a cell?
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Ribosomes are the sites of protein synthesis in the cell, where they translate mRNA into proteins.
21. Which of the following is a saturated fatty acid?
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Stearic acid is a saturated fatty acid, as it contains no double bonds between carbon atoms.
22. What is the complementary base pair of A-T in RNA?
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In RNA, Adenine (A) pairs with Uracil (U), forming a complementary base pair.
23. Which molecule serves as the primary carrier of energy in cells?
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Adenosine triphosphate (ATP) serves as the primary carrier of energy in cells, providing energy for most cellular processes.
24. Which vitamin is important for blood clotting?
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Vitamin K is essential for blood clotting, as it is involved in the synthesis of clotting factors.
25. Which element is a component of chlorophyll?
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Magnesium is a component of the chlorophyll molecule and plays a crucial role in photosynthesis.