Read the following statements about plant hormones:
1. Auxins promote apical dominance.
2. Cytokinins promote senescence.
3. Ethylene accelerates fruit ripening.
Which of the above statements are correct?
Show answer & explanation
Correct answer: B
Explanation
Correct Answer
Only 1 and 3 are correct.
Explanation
Auxins are plant hormones that promote apical dominance. They inhibit the growth of lateral buds and encourage the growth of the main stem; therefore, Statement 1 is correct.
Cytokinins promote cell division and delay senescence (aging) in leaves. Hence, Statement 2 is incorrect.
Ethylene is a gaseous plant hormone that accelerates the ripening of fruits. Therefore, Statement 3 is correct.
Thus, only Statements 1 and 3 are correct.
Key Points
• Auxins promote apical dominance.
• Cytokinins stimulate cell division.
• Cytokinins delay senescence rather than promote it.
• Ethylene accelerates the fruit-ripening process.
Additional Facts
• Auxin was discovered by F. W. Went.
• Kinetin is a well-known example of a cytokinin.
• Ethylene is the only major gaseous plant hormone.
Important Questions
Question: Which plant hormone promotes apical dominance?
Answer: Auxin.
Question: Which plant hormone accelerates fruit ripening?
Answer: Ethylene.