Which receptors detect mechanical changes such as pressure and touch?

• A. Photoreceptors
• B. Mechanoreceptors
• C. Chemoreceptors
• D. Thermoreceptors

Answer: (B)

Mechanoreceptors are the sensors that respond to mechanical changes like pressure, touch, vibration, and stretch. They convert physical forces into electrical signals by deforming their membrane and opening ion channels, which starts nerve impulses. In the skin you have different mechanoreceptors tuned to various aspects of touch: some respond quickly to changing stimuli (like light touch or deep pressure), while others provide information about texture, shape, or sustained pressure.

Other options detect different kinds of stimuli: photoreceptors respond to light, chemoreceptors to chemical substances, and thermoreceptors to temperature. So for sensing mechanical changes such as pressure and touch, the relevant receptors are mechanoreceptors.