What is a receptor?

A receptor is a structure that detects a change in either the internal or external environment, and transmits information to a modulator to carry out an appropriate response. There are a number of different types of receptors which are designed to detect a number of different types of stimuli.

What are the types of receptors?

There are some predominant types of receptors which you need to know.

• Thermoreceptors: These receptors detect changes in temperature. There are two types of thermoreceptors; hot thermoreceptors, which detect heat, and cold thermoreceptors, which detect cold. Thermoreceptors can either be found in the skin to detect changes in the external environment, and the hypothalamus which detects changes in the internal environment.

• Osmoreceptors: These receptors detect changes in osmotic pressure, and is found in the hypothalamus.

• Chemoreceptors: These receptors detect changes in the levels of different chemicals found in the body, for example, carbon dioxide, oxygen, hydrogen ion levels etc., and these receptors are always located internally.

• Touch receptors: These receptors detect touch/pressure, and are mainly found in the skin.

• Pain receptors: These receptors detect pain and damage to tissues, and are found in the skin and most organs (but are not found in the brain!).