Skin Receptors Quiz

Study Notes

Cutaneous Receptors Overview

Skin contains various types of receptors, each responding to different stimuli.
Receptors are innervated by axons.

Meissner Corpuscle

Sensitive to flutter and light touch.
Located in the superficial layers of skin.
Composed of nerve endings enclosed in connective tissue.
Rapidly adapting, firing only during stimulus onset and offset.

Pacinian Corpuscle

Responsive to vibration.
Found in the deep layers of skin.
Like Meissner, consists of encapsulated nerve endings.
Rapidly adapting receptor.

Ruffini Ending/Corpuscle

Detects skin stretching.
Located in the deep skin layers.
Consists of enlarged nerve endings.
Slowly adapting, continuing to fire as long as the stimulus persists.

Merkel Cells

Respond to steady pressure and texture.
Situated in the superficial layers of skin.
Composed of enlarged nerve endings.
Slowly adapting receptor, providing ongoing stimulus information.

Free Nerve Endings

Respond to temperature, pain, itch, and hair follicle movement.
Found around hair roots and beneath the skin surface.
Comprised of unmyelinated nerve endings.
Exhibit variable adaptation characteristics.

Nociceptors

Specialized receptors that respond to noxious stimuli that can damage tissue (chemical, mechanical, thermal).
Utilized by free nerve endings.
Activate reflexive responses via spinal cord or send signals to the cerebral cortex for conscious sensation of pain or itch.

Temperature Receptors

Cold receptors are activated below 37°C; warm receptors function between 37°-45°C.
Adapt slowly between 20°-40°C, but nociceptors recognize pain outside this range.
Chemicals (e.g., menthol, capsaicin) can influence temperature receptors.

Transduction Process

Converts sensory stimuli into action potentials.
Triggered by membrane stretch opening mechanical gateways for ion influx (e.g., Na+).
Action potential generated upon reaching the threshold.

Slowly Adapting Receptors

Trigger continuous nerve impulses as long as the stimulus persists.
Examples include Merkel cells and Ruffini endings.

Rapidly Adapting Receptors

Fire briefly during the onset and/or offset of a stimulus.
Includes Pacinian and Meissner corpuscles.

Transduction Timing

Slow transduction leads to many action potentials throughout the stimulus duration.
Rapid transduction is characterized by concentrated bursts of action potentials during changes in the stimulus.

Transduction Intensity

Higher stimulus intensity correlates with increased frequency of action potentials.

Transduction Modality

Refers to the type of stimulus, determined by skin indentation and stimulus frequency.
Specific receptors fire according to their strengths, sending appropriate action potentials.

Transduction Location

Different receptors exhibit overlapping and variable sensitivity areas.
Meissner (rapidly adapting) and Merkel (slowly adapting) have small, specific sensory fields.
Pacinian (rapidly adapting) and Ruffini (slowly adapting) possess larger sensory fields.

Description

Test your knowledge on the various types of cutaneous receptors in the skin. Explore the functions, locations, and adaptations of Meissner corpuscles, Pacinian corpuscles, Ruffini endings, Merkel cells, and free nerve endings. This quiz helps solidify your understanding of sensory receptors in dermatology.