Question

deciduous plants shed their leaves during hot summer or in autumn.

This process of shedding of leaves is called abscission. Apart from

physiological changes what anatomical mechanism is involved in the

abscission of leaves.

Answer 1

Abscission occurs when a separation zone is formed at the base of the petiole. This separation zone is composed of the cells with weaker cell walls. In autumn when the bottom cell layer expands the weak cell walls of the top layer break and he leaf falls down. Lack of chlorophyll is also a reason that the cells become weaker and abscission takes place. Abscisic acid is a plant hormone that also initiates the shedding of leaves.