Short answerModerate1 mark
3(b)
State the main functions of the following:
Cytokinins
Topic: Cytokinins
Previous-year question practice database
Answer
Exam answer
Cytokinins promote CELL DIVISION (cytokinesis) in plants. They also delay the ageing of leaves, help in the differentiation of tissues, and break the dormancy of seeds and buds.
Explanation
The name carries the function: CYTO (cell) + KINESIS (division). Cell division.
The four plant hormones distinguished by their chief effect, which is how examiners test them: AUXIN — cell ELONGATION; controls tropisms GIBBERELLIN — stem and fruit elongation; breaks seed dormancy CYTOKININ — cell DIVISION ABSCISIC ACID — the stress hormone; closes stomata, causes dormancy and leaf fall
Note the neat contrast: auxin makes cells BIGGER, cytokinin makes them MORE NUMEROUS.
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