Which sensory receptor is located at the epidermis-dermis junction?

Which sensory receptor is located at the epidermis-dermis junction?

• A. Free nerve endings
• B. Pacinian corpuscles
• C. Meissner's corpuscles
• D. Merkel cells

Answer: (D)

The main idea is that some touch receptors sit right at the border between the epidermis and dermis to detect fine, sustained touch. Merkel cells are located in the basal layer of the epidermis, at the epidermis-dermis junction, and each one associates with a nerve ending to form a Merkel disk. This placement and connection give high-resolution touch discrimination and sensitivity to shape and texture, especially important in areas like the fingertips. Merkel cells are slow-adapting, meaning they continue to signal with a steady stimulus, which is ideal for recognizing continuous pressure or details of an object’s surface. Other receptors have different locations and roles: free nerve endings sense pain and temperature and are spread throughout the skin; Meissner’s corpuscles reside in the dermal papillae of hairless skin and respond to light touch; Pacinian corpuscles lie deeper in the dermis/hypodermis and detect deep pressure and vibration.

The main idea is that some touch receptors sit right at the border between the epidermis and dermis to detect fine, sustained touch. Merkel cells are located in the basal layer of the epidermis, at the epidermis-dermis junction, and each one associates with a nerve ending to form a Merkel disk. This placement and connection give high-resolution touch discrimination and sensitivity to shape and texture, especially important in areas like the fingertips. Merkel cells are slow-adapting, meaning they continue to signal with a steady stimulus, which is ideal for recognizing continuous pressure or details of an object’s surface. Other receptors have different locations and roles: free nerve endings sense pain and temperature and are spread throughout the skin; Meissner’s corpuscles reside in the dermal papillae of hairless skin and respond to light touch; Pacinian corpuscles lie deeper in the dermis/hypodermis and detect deep pressure and vibration.