Question

Response to contact is called as
(a) Thermotaxis
(b) Thigmotaxis
(c) Chemotaxis
(d) Geotropism

Answer 1

Hint:This is an innate behavioral response and this type of response is shown by a living organism in which a stimulus other than light and heat is applied to that organism. The organisms that show this type of movement that are able to move and demonstrate the direction of stimuli.

Complete answer:Thigmotaxis is the response of a living organism towards the proximity of a physical discontinuity in the environment or simply a physical contact.

It differs from thigmotropism that occurs in the plants and is generally in the form of movement of some parts of the plant because, in Thigmotaxis, there is some sort of movement shown by the whole organism in the form of change in place. For example, Thigmotaxis is shown by the larvae of codling moths that use the thigmotactic senses to locate the fruits and then feed on them.
It is a type of innate behavioral response towards the touch and similar stimuli. Depending upon the types of sensory organs present in the organism, it samples the environment and then determines the type of movement it needs to perform.

So, the correct answer is ‘Thigmotaxis’.
Note:1. Thermotaxis is a migration of the living organisms along a temperature gradient and this type of response is used by some slime molds and other small organisms that sense small variations in temperature in water and move towards the region of ideal temperature.
2. Chemotaxis occurs in response to the chemicals and seen easily in bacteria such as E.coli. that uses this sense to detect the sugar gradient.