Free NSAA Biology Questions and Answers — Questions and Answers
Question 1: Which of the following is the primary structure of a protein?
- The three-dimensional shape formed by hydrogen bonding
- The sequence of amino acids (Correct answer)
- The overall shape formed by interactions between multiple polypeptide chains
- The shape formed by disulfide bridges and ionic bonds
Correct answer: The sequence of amino acids
The primary structure of a protein is the linear sequence of amino acids in its polypeptide chain.
Question 2: In which phase of the cell cycle does DNA replication occur?
- S phase (Correct answer)
- G1 phase
- G2 phase
- M phase
Correct answer: S phase
DNA replication occurs during the S phase (synthesis phase) of the cell cycle.
Question 3: Which organelle is responsible for producing ATP through oxidative phosphorylation?
- Mitochondrion (Correct answer)
- Nucleus
- Ribosome
- Lysosome
Correct answer: Mitochondrion
The mitochondrion is responsible for producing ATP through oxidative phosphorylation in the process of cellular respiration.
Question 4: What is the function of ribosomes in the cell?
- Protein synthesis (Correct answer)
- DNA replication
- Lipid synthesis
- Waste breakdown
Correct answer: Protein synthesis
Ribosomes are responsible for synthesizing proteins by translating messenger RNA.
Question 5: Which of the following best describes the process of osmosis?
- Movement of water from an area of low solute concentration to high solute concentration (Correct answer)
- Movement of solutes from an area of high concentration to low concentration
- Movement of water from an area of high solute concentration to low solute concentration
- Movement of water against the concentration gradient
Correct answer: Movement of water from an area of low solute concentration to high solute concentration
Osmosis is the movement of water molecules through a selectively permeable membrane from an area of low solute concentration to an area of high solute concentration.
Question 6: Which of the following statements about enzymes is true?
- Enzymes decrease the activation energy of a reaction (Correct answer)
- Enzymes are consumed during the reaction they catalyze
- Enzymes are specific to a single type of reaction
- Enzymes work equally well at all pH levels
Correct answer: Enzymes decrease the activation energy of a reaction
Enzymes function by lowering the activation energy required for a reaction to occur, thereby speeding up the reaction.
Question 7: What is the primary role of chlorophyll in photosynthesis?
- Absorbing light energy (Correct answer)
- Absorbing water
- Synthesizing glucose
- Releasing oxygen
Correct answer: Absorbing light energy
Chlorophyll is the pigment in plants that absorbs light energy, which is then used to convert carbon dioxide and water into glucose during photosynthesis.
Question 8: Which of the following processes results in the formation of gametes?
- Meiosis (Correct answer)
- Mitosis
- Binary fission
- Budding
Correct answer: Meiosis
Meiosis is the process that results in the formation of gametes (sperm and eggs), reducing the chromosome number by half.
Question 9: What is the main function of the Golgi apparatus in the cell?
- Modifying, sorting, and packaging proteins for secretion (Correct answer)
- Synthesizing proteins
- Generating ATP
- Breaking down waste materials
Correct answer: Modifying, sorting, and packaging proteins for secretion
The Golgi apparatus modifies, sorts, and packages proteins and lipids for secretion or delivery to other organelles.
Question 10: Which type of bond is formed between the oxygen and hydrogen atoms within a single water molecule?
- Covalent bond (Correct answer)
- Ionic bond
- Hydrogen bond
- Metallic bond
Correct answer: Covalent bond
The oxygen and hydrogen atoms within a single water molecule are held together by covalent bonds, where electrons are shared between atoms.
Question 11: Which of the following statements about genetic mutations is true?
- Mutations can be caused by environmental factors (Correct answer)
- All mutations are harmful
- Mutations only occur during DNA replication
- Mutations are always beneficial
Correct answer: Mutations can be caused by environmental factors
Mutations can be caused by various factors, including environmental influences such as radiation, chemicals, and viruses.
