Q41. 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) Facilitating cell communication
d) Detecting environmental signals
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Correct Answer: b) Providing structural support to the cell
Explanation: While the cell membrane does provide some structural support to the cell by maintaining its shape, its primary functions include regulating the passage of substances, facilitating cell communication, and detecting environmental signals.
Q42. What is the term for the process by which living organisms convert light energy into chemical energy?
a) Respiration
b) Fermentation
c) Photosynthesis
d) Aerobic metabolism
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Correct Answer: c) Photosynthesis
Explanation: Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy into chemical energy stored in glucose and other organic molecules, using carbon dioxide and water as reactants.
Q43. Which of the following is a characteristic feature of prokaryotic cells?
a) Presence of membrane-bound organelles
b) Linear chromosomes
c) Nucleus containing genetic material
d) Absence of a cell wall
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Correct Answer: d) Absence of a cell wall
Explanation: Prokaryotic cells, such as bacteria and archaea, lack membrane-bound organelles, including a nucleus. They typically have a single circular chromosome and a cell wall, which provides structural support and protection.
Q44. What is the primary function of the mitochondria in eukaryotic cells?
a) Protein synthesis
b) Lipid synthesis
c) ATP production
d) Detoxification
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Correct Answer: c) ATP production
Explanation: Mitochondria are often referred to as the powerhouse of the cell because their primary function is to produce adenosine triphosphate (ATP), which serves as the main energy currency of the cell through aerobic cellular respiration.
Q45. Which of the following is an example of an autotrophic organism?
a) Dog
b) Rose bush
c) Algae
d) Fungi
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Correct Answer: c) Algae
Explanation: Algae are examples of autotrophic organisms that can produce their own food through photosynthesis, using light energy to convert carbon dioxide and water into organic molecules like glucose.
Q46. What is the term for the specialized structures within cells that carry out specific functions?
a) Organelles
b) Enzymes
c) Ribosomes
d) Proteins
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Correct Answer: a) Organelles
Explanation: Organelles are specialized structures within cells that perform specific functions necessary for cellular processes. Examples include the nucleus, mitochondria, chloroplasts, and endoplasmic reticulum.
Q47. Which of the following is a characteristic of viruses?
a) Cellular structure
b) Ability to reproduce independently
c) Presence of ribosomes
d) Genetic material enclosed in a protein coat
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Correct Answer: d) Genetic material enclosed in a protein coat
Explanation: Viruses are acellular infectious agents composed of genetic material, either DNA or RNA, enclosed in a protein coat called a capsid. They lack cellular structure and rely on host cells for reproduction.
Q48. What is the process by which cells become specialized in structure and function during development?
a) Differentiation
b) Replication
c) Mutation
d) Proliferation
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Correct Answer: a) Differentiation
Explanation: Differentiation is the process by which cells undergo specialization to become different cell types with specific structures and functions during the development of multicellular organisms.
Q49. Which of the following is NOT a component of the scientific method?
a) Observation
b) Hypothesis
c) Conclusion
d) Assumption
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Correct Answer: d) Assumption
Explanation: Assumptions are not part of the scientific method. Instead, the scientific method involves making observations, forming hypotheses, conducting experiments, analyzing data, and drawing conclusions based on evidence.
Q50. What is the term for the process by which organisms evolve beneficial traits that increase their fitness in a given environment?
a) Adaptation
b) Mutation
c) Genetic drift
d) Gene flow
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Correct Answer: a) Adaptation
Explanation: Adaptation is the evolutionary process by which organisms develop beneficial traits that enhance their survival and reproductive success in a given environment. These traits are favored by natural selection and contribute to the organism’s fitness.