Name the parts (a) to (e) in the following diagram.

What is the term given to the sequence of events occurring in the diagram?

OR

(a) What is tropism?

(b) How do auxins promote the growth of a tendril around a support?

(a) Receptors (b) Sensory Neuron (c) Spinal Cord (d) Relay Neuron (e) Motor Neuron

The term given to the sequence of events occurring here is the Reflex action.

OR

(a) Tropisms: These are the growth-related movements which are very slow and always in the direction of stimulus. All parts of a plant (roots, stem and leaves etc.) exhibit these movements. For example, Phototropism is the growth towards sunlight, Chemotropism is the growth towards chemicals, etc.

(b) Auxin is one of the major growth promoting plant hormones. In tendrils, the auxin is present in the tips. When a tendril comes in contact with a support, auxin stimulates faster cell growth on the opposite side. This makes the tendril curve and bend towards the support. This curving tendril can then encircle the support and sling around it.