Question

Which one of the five categories of sensory receptors is primarily dedicated to external stimuli?

Short answer

Touch, taste, sound, smell, and vision are the external stimuli. The electromagnetic sensory receptor will respond to external stimuli; light energy converts electrical signals.

Step-by-step solution

Sensory receptors

Sensory receptors respond when changes occur in the surrounding environment. These receptors detect the stimuli. The receptors start sensory transduction by creating potential in a cell. These receptors are responsible for responding to internal and external stimuli.

Electromagnetic receptor 

An electromagnetic receptor is one of the types of sensory receptors. Electromagnetic receptors located in the cornea and rods of the eyes are responsible for color and brightness.

Working of electromagnetic receptor on external stimuli

The electromagnetic receptor acts as external stimuli for vision. These receptors respond to external stimuli and stimulate physiological functions. A single pulse of light causes activation of the rod receptor potential for more than a second.

The receptor potential is proportional to the light intensity. The sensory receptors like chemoreceptors react to chemical signals, while non-electromagnetic receptors respond to non-photon, responsible for internal and internal stimuli.