1. Which of the following is a monosaccharide?
Answer:
Explanation:
Glucose is a simple sugar or monosaccharide, while the others are disaccharides.
2. Which base is not present in DNA?
Answer:
Explanation:
Uracil is present in RNA, whereas Thymine is its counterpart in DNA.
3. The secondary structure of a protein is due to:
Answer:
Explanation:
The α-helix and β-pleated sheet structures of proteins are due to hydrogen bonding.
4. Which of the following is a polysaccharide?
Answer:
Explanation:
Cellulose is a complex carbohydrate or polysaccharide. The others are simple sugars.
5. Enzymes are:
Answer:
Explanation:
Enzymes are biological catalysts and are primarily made up of proteins.
6. Which vitamin is water-soluble?
Answer:
Explanation:
Vitamin C (ascorbic acid) is water-soluble, whereas the others are fat-soluble.
7. Which amino acid has a sulfur-containing side chain?
Answer:
Explanation:
Cysteine contains a thiol (-SH) group in its side chain.
8. The primary structure of a protein is determined by:
Answer:
Explanation:
The primary structure refers to the linear sequence of amino acids in the polypeptide chain.
9. DNA replication is:
Answer:
Explanation:
In semi-conservative replication, each new DNA molecule consists of one old and one new strand.
10. Glycogen is a storage form of glucose in:
Answer:
Explanation:
In animals, excess glucose is stored as glycogen, while in plants, it's stored as starch.
11. Which base pairs with adenine in RNA?
Answer:
Explanation:
In RNA, adenine pairs with uracil.
12. Which sugar is found in RNA?
Answer:
Explanation:
RNA contains ribose sugar, while DNA contains deoxyribose.
13. Which is the smallest biomolecule?
Answer:
Explanation:
Amino acids are smaller than nucleotides, carbohydrates, or lipids.
14. Which biomolecule is primarily responsible for genetic information?
Answer:
Explanation:
DNA, a type of nucleic acid, carries genetic information.
15. In the lock and key model of enzyme action, the key refers to:
Answer:
Explanation:
The substrate fits into the enzyme like a key fits into a lock.
16. Which of the following biomolecules is amphipathic?
Answer:
Explanation:
Lipids, especially phospholipids, have both hydrophilic (water-attracting) and hydrophobic (water-repelling) parts, making them amphipathic.
17. The bond between two amino acids is called:
Answer:
Explanation:
A peptide bond is formed between the carboxyl group of one amino acid and the amino group of another.
18. Which biomolecule serves as an energy currency of the cell?
Answer:
Explanation:
ATP (Adenosine triphosphate) acts as an energy currency for cellular activities.
19. Fatty acids with no double bonds are referred to as:
Answer:
Explanation:
Fatty acids with no double bonds are saturated, meaning they have the maximum possible number of hydrogen atoms.
20. The helical structure of DNA was proposed by:
Answer:
Explanation:
The double helix structure of DNA was proposed by James Watson and Francis Crick.