Question

Assertion (A): The effect of auxin hormone on the growth of roots exactly opposite to that on a stem.

Reason (R): Auxin hormone increases the rate of growth in root and decreases the rate of growth in stem.

Options

• Both A and R are true and R is the correct explanation of A.

• Both A and R are true but R is not the correct explanation of A.

• A is true but R is false.

• A is false but R is true.

Answer 1

A is true but R is false.

Explanation:

The assertion is true because auxin produces opposing physical responses in different organs; it stimulates cell elongation in stems but inhibits cell elongation in roots. The reason is completely false because it states the exact inverse of this biological mechanism. Auxin actually increases the rate of growth and elongation in the stem while actively slowing down or decreasing the rate of elongation in the roots at equivalent concentrations.