Sensory receptors in the skin

What are the three main functional groups of neurons?

Sensory neurons (afferent), motor neurons (efferent), and interneurons.

What is the role of sensory neurons?

They carry sensory information from the periphery to the central nervous system (CNS).

What are afferent nerve endings?

The peripheral processes of sensory neurons that respond to mechanical, thermal, or painful stimuli.

What are the three main types of sensory receptors?

Interoceptors (viscera), exteroceptors (skin), and proprioceptors (muscles and joints).

What are exteroceptors?

Sensory receptors in the skin that detect external stimuli like pain, temperature, and touch.

What are the two structural types of sensory receptors?

Encapsulated (surrounded by a structure, like corpuscles) and unencapsulated (free nerve endings).

What is meant by sensory modality?

The type of sensation detected, such as pain, touch, temperature, or vibration.

What are mechanoreceptors?

Receptors that respond to mechanical deformation, such as touch or pressure.

What are thermoreceptors?

Receptors that detect changes in temperature (hot or cold).

What are nociceptors?

Pain receptors that respond to tissue damage or potentially harmful stimuli.

What are proprioceptors?

Receptors in muscles, tendons, and joints that provide information about body position and movement.

What is a receptor (generator) potential?

A graded change in membrane potential in response to a stimulus that may lead to an action potential.

What is rapid adaptation in sensory receptors?

Receptors respond quickly to a stimulus but stop firing if the stimulus is constant (e.g., Meissner's corpuscles).

What is slow adaptation in sensory receptors?

Receptors continue to respond for a longer time to a constant stimulus (e.g., Ruffini endings).

What are the main types of nerve fibers in the skin?

A fibers (myelinated, fast), B fibers (lightly myelinated), and C fibers (unmyelinated, slow).

What are free nerve endings?

Unencapsulated receptors that detect pain, temperature, and itch.

What are Meissner’s corpuscles?

Rapidly adapting mechanoreceptors in the dermis, sensitive to light touch.

What are Pacinian corpuscles?

Rapidly adapting receptors that detect vibration and deep pressure.

What are Ruffini endings?

Slowly adapting receptors that detect skin stretch.

What is the difference between rapidly and slowly adapting receptors?

Rapidly adapting receptors stop firing quickly when a stimulus is constant, while slowly adapting receptors continue to fire.