Q11. What is the process by which cells convert glucose and oxygen into carbon dioxide, water, and ATP?
a) Photosynthesis
b) Respiration
c) Fermentation
d) Glycolysis
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Correct Answer: b) Respiration
Explanation: Respiration is the biochemical process by which cells break down glucose and oxygen to produce carbon dioxide, water, and ATP (adenosine triphosphate), releasing energy that fuels cellular activities.
Q12. Which of the following is NOT a characteristic of prokaryotic cells?
a) Lack of a nucleus
b) Presence of membrane-bound organelles
c) Small size
d) Presence of ribosomes
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Correct Answer: b) Presence of membrane-bound organelles
Explanation: Prokaryotic cells lack membrane-bound organelles such as a nucleus, mitochondria, or endoplasmic reticulum. Instead, their genetic material is typically found in a nucleoid region, and they have ribosomes for protein synthesis.
Q13. What is the process by which a cell engulfs particles or other cells into its cytoplasm?
a) Endocytosis
b) Exocytosis
c) Phagocytosis
d) Pinocytosis
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Correct Answer: c) Phagocytosis
Explanation: Phagocytosis is the process by which a cell engulfs solid particles, such as bacteria or cellular debris, into its cytoplasm using extensions of its cell membrane called pseudopodia.
Q14. Which of the following is a function of the Golgi apparatus in eukaryotic cells?
a) Protein synthesis
b) Lipid synthesis
c) Sorting and modification of proteins
d) ATP production
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Correct Answer: c) Sorting and modification of proteins
Explanation: The Golgi apparatus plays a key role in sorting, modifying, and packaging proteins and lipids synthesized by the endoplasmic reticulum. It acts as a distribution center for molecules destined for secretion or transport to other organelles.
Q15. What is the term for the movement of water across a semipermeable membrane from an area of low solute concentration to an area of high solute concentration?
a) Osmosis
b) Diffusion
c) Active transport
d) Facilitated diffusion
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Correct Answer: a) Osmosis
Explanation: Osmosis is the passive movement of water molecules across a semipermeable membrane from an area of low solute concentration to an area of high solute concentration, equalizing the solute concentration on both sides of the membrane.
Q16. Which of the following is the primary pigment responsible for capturing light energy during photosynthesis?
a) Chlorophyll
b) Carotenoid
c) Phycobilin
d) Xanthophyll
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Correct Answer: a) Chlorophyll
Explanation: Chlorophyll is the primary pigment found in the chloroplasts of green plants and algae. It absorbs light energy, particularly in the blue and red regions of the electromagnetic spectrum, to drive the process of photosynthesis.
Q17. Which of the following is a function of the ribosomes in cells?
a) Synthesis of lipids
b) Synthesis of proteins
c) Storage of genetic material
d) Generation of energy
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Correct Answer: b) Synthesis of proteins
Explanation: Ribosomes are cellular organelles responsible for protein synthesis. They translate the genetic information encoded in messenger RNA (mRNA) into polypeptide chains, which fold into functional proteins.
Q18. What is the term for the process by which cells regulate their internal environment to maintain a stable, balanced state?
a) Osmoregulation
b) Homeostasis
c) Thermoregulation
d) Metabolism
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Correct Answer: b) Homeostasis
Explanation: Homeostasis is the process by which cells, tissues, and organisms regulate and maintain a stable internal environment, despite fluctuations in external conditions, through various physiological and biochemical mechanisms.
Q19. Which of the following is a function of the cell membrane?
a) Regulation of cellular activities
b) Protection of cellular contents
c) Selective permeability
d) All of the above
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Correct Answer: d) All of the above
Explanation: The cell membrane, or plasma membrane, serves multiple functions in cells, including regulating cellular activities, protecting cellular contents, and controlling the passage of substances through selective permeability.
Q20. Which of the following is NOT a component of the central dogma of molecular biology?
a) Transcription
b) Translation
c) Replication
d) Mutation
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Correct Answer: d) Mutation
Explanation: The central dogma of molecular biology describes the flow of genetic information within a biological system, including replication (DNA synthesis), transcription (RNA synthesis), and translation (protein synthesis). Mutation refers to changes in the DNA sequence and is not part of the central dogma’s flow of information.