NEET Biology: Phases of Plant growth and plant growth rate Practice Questions
11 free multiple-choice questions on Phases of Plant growth and plant growth rate (Plant Growth and Development) for NEET Biology, each with the correct answer and a step-by-step explanation. Attempt a question, then reveal the solution to check your reasoning.
Practice thousands more NEET questions in the app →Q1. Which tissue is responsible for the increase in the girth (width) of the stem and root during mature growth?
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Correct answer: C — Cambium
The vascular cambium, which is a type of lateral meristem, is responsible for secondary growth, leading to the increase in girth.
Q2. Vernalization is a process required for flowering in many plants. This process is primarily induced by:
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Correct answer: B — Cold temperature exposure
Vernalization is the requirement of a period of cold temperature exposure to trigger flowering in many plants.
Q3. Etiolation is the condition where plants grow excessively long and thin due to insufficient light. This condition occurs in plants grown in:
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Correct answer: A — Dark conditions
Etiolation is the etiolation of seedlings grown in the dark or with insufficient light, as they rapidly elongate to reach the light source.
Q4. In a seedling, the development sequence generally follows which order?
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Correct answer: D — Vegetative growth followed by reproductive growth
Plants first develop roots and shoots (vegetative growth) before they enter the reproductive phase (flowering/seed production).
Q5. Which hormone is crucial for the breaking of seed dormancy and promoting stem elongation by stimulating the action of gibberellins?
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Correct answer: A — Gibberellin
Gibberellins are essential for breaking seed dormancy and promoting stem elongation in plants.
Q6. Which of the following phytohormones is primarily responsible for cell elongation and differentiation in plants?
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Correct answer: A — Gibberellin
Gibberellins are critical for promoting stem elongation and seed germination, directly influencing cell elongation and differentiation.
Q7. Which stage of plant growth is primarily responsible for the enlargement and maturation of the plant structure?
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Correct answer: A — Vegetative growth
Vegetative growth is the phase characterized by the increase in size and development of stems, leaves, and roots, which leads to the enlargement of the plant structure.
Q8. What is the primary contribution of the apical meristem to the growth of a plant?
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Correct answer: C — Increase in stem and root length
The apical meristem is located at the tips of the shoots and roots and is responsible for the elongation and primary growth of the plant structures.
Q9. The cells responsible for the increase in the girth (width) of the plant are derived from which type of meristem?
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Correct answer: D — Lateral meristem
The lateral meristems, specifically the vascular cambium and cork cambium, are responsible for secondary growth, which increases the girth (width) of the plant.
Q10. Which plant growth hormone is primarily responsible for promoting cell elongation and phototropism?
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Correct answer: A — Auxin
Auxin is the primary growth hormone responsible for cell elongation and mediating phototropism (growth response to light).
Q11. Apical dominance is the phenomenon where the growth of the shoot tip inhibits the growth of lateral buds. This is primarily controlled by which plant hormone?
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Correct answer: C — Auxin
Auxin is the primary growth hormone that exhibits apical dominance, directing the growth of the shoot tip and suppressing the growth of lateral buds.
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