Short answerHard1 mark
1(g)
Expand the following biological abbreviations:
IAA
Topic: IAA
Previous-year question practice database
Answer
Exam answer
INDOLE-3-ACETIC ACID.
Explanation
IAA is the commonest naturally occurring AUXIN. It causes cell ELONGATION and is responsible for the tropic movements — in a shoot lit from one side it migrates to the SHADED side, whose cells then elongate more, bending the shoot towards the light.
So when a question mentions IAA, it is asking about auxin.
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