Q11. What is the function of the Golgi apparatus in a cell?
a) Protein synthesis
b) Lipid synthesis
c) Packaging and modifying proteins
d) DNA replication
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Correct Answer: c) Packaging and modifying proteins
Explanation: The Golgi apparatus is responsible for packaging and modifying proteins synthesized in the endoplasmic reticulum. It receives proteins in vesicles from the ER, modifies them by adding sugars or lipids, sorts them, and packages them into vesicles for transport to other parts of the cell or for secretion.
Q12. Which of the following is NOT a function of the mitochondria?
a) ATP production
b) Cellular respiration
c) Photosynthesis
d) Regulation of apoptosis
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Correct Answer: c) Photosynthesis
Explanation: Mitochondria are known as the powerhouse of the cell because they produce ATP through cellular respiration. They also play a crucial role in regulating apoptosis, or programmed cell death. However, they are not involved in photosynthesis, which occurs in chloroplasts in plant cells.
Q13. What is the main function of the ribosomes in a cell?
a) Energy production
b) DNA replication
c) Protein synthesis
d) Lipid synthesis
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Correct Answer: c) Protein synthesis
Explanation: Ribosomes are cellular structures responsible for protein synthesis. They translate the genetic code from messenger RNA (mRNA) into amino acids, which then form proteins. This process occurs in both prokaryotic and eukaryotic cells.
Q14. Which organelle is responsible for detoxifying harmful substances in a cell?
a) Lysosome
b) Peroxisome
c) Golgi apparatus
d) Endoplasmic reticulum
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Correct Answer: b) Peroxisome
Explanation: Peroxisomes are responsible for detoxifying harmful substances in a cell, such as hydrogen peroxide, through the action of enzymes like catalase. They also play roles in lipid metabolism and the conversion of fatty acids to carbohydrates.
Q15. Which of the following is NOT a function of the cell membrane?
a) Regulating the passage of substances into and out of the cell
b) Providing structural support to the cell
c) Cell communication
d) Energy production
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Correct Answer: d) Energy production
Explanation: The cell membrane, also known as the plasma membrane, regulates the passage of substances into and out of the cell, provides structural support, and facilitates cell communication through receptors and signaling molecules. However, it is not directly involved in energy production.
Q16. What is the function of mitochondria in a cell?
a) Synthesis of proteins
b) Energy production
c) Storage of genetic material
d) Regulation of cell cycle
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Correct Answer: b) Energy production
Explanation: Mitochondria are often referred to as the powerhouse of the cell due to their role in producing adenosine triphosphate (ATP), which is the primary energy currency of the cell. Through cellular respiration, mitochondria convert nutrients into ATP, providing energy for various cellular processes.
Q17. Which of the following is NOT a function of the liver?
a) Detoxification
b) Carbohydrate metabolism
c) Blood filtration
d) Protein synthesis
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Correct Answer: c) Blood filtration
Explanation: While the liver performs many vital functions such as detoxification, carbohydrate metabolism, and protein synthesis, blood filtration is primarily carried out by the kidneys, not the liver. The liver’s main role in blood involves processing nutrients and removing toxins before the blood reaches other parts of the body.
Q18. What is the main function of white blood cells?
a) Transportation of oxygen
b) Fighting infection
c) Blood clotting
d) Regulation of blood sugar levels
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Correct Answer: b) Fighting infection
Explanation: White blood cells, also known as leukocytes, are key components of the immune system. Their primary function is to defend the body against infections and foreign invaders such as bacteria, viruses, and other pathogens. They do so by identifying and destroying these harmful agents through various mechanisms, including phagocytosis and production of antibodies.
Q19. Which of the following is NOT a component of the central nervous system (CNS)?
a) Brain
b) Spinal cord
c) Nerves
d) None of the above
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Correct Answer: c) Nerves
Explanation: The central nervous system (CNS) consists of the brain and spinal cord, which are responsible for processing and integrating sensory information, coordinating responses, and regulating bodily functions. Nerves, on the other hand, belong to the peripheral nervous system (PNS), which connects the CNS to the rest of the body, transmitting signals to and from various organs and tissues.
Q20. What is the function of chlorophyll in plants?
a) Absorption of water
b) Photosynthesis
c) Regulation of gas exchange
d) Storage of nutrients
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Correct Answer: b) Photosynthesis
Explanation: Chlorophyll is a pigment found in chloroplasts of plant cells, responsible for capturing light energy during photosynthesis. This process involves converting light energy, water, and carbon dioxide into glucose and oxygen. Chlorophyll molecules absorb light energy from the sun and transfer it to other molecules, initiating the biochemical reactions necessary for photosynthesis to occur.