Question
Two identical potted plants were used to investigate plant responses.
Plant A was placed on a clinostat that continually rotated. Plant B was not rotated.
Both plants were then placed on their sides and kept in the dark.
Fig. 4.1 shows the two plants at the start of the experiment and after seven days.
(a) State the name of the response shown by the shoot of plant B.
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(b) Explain the reason for constantly rotating plant A.
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(c) (i) State the name of the plant hormone that causes the response of the shoot of plant B.
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(ii) Explain how the plant hormone causes the response of plant B.
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(d) Seeds germinate in the soil. The seedlings that grow from seeds show the same response as
shown by plant B in Fig. 4.1.
Explain the advantages of this response to the survival of seedlings and mature plants.
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Answer/Explanation
Ans:
