Autonomic Nervous System and Sensory Receptors

Flashcards covering key concepts from the autonomic nervous system and sensory receptors.

Sympathetic Division of ANS

Prepares the body for physical activity; increases alertness, pulse, and blood pressure ('fight or flight').

Parasympathetic Division of ANS

Promotes calming, digestion, and waste elimination ('rest and digest').

Sympathetic Trunk/Chain Ganglia

Relay sympathetic signals to various organs.

White Rami Communicans

Carry preganglionic sympathetic fibers from spinal cord to sympathetic ganglia.

Gray Rami Communicans

Carry postganglionic sympathetic fibers from ganglia to spinal nerves.

General Senses

Widely distributed receptors for touch, temperature, pain, pressure.

Special Senses

Senses with specialized organs - taste, smell, hearing, vision, balance.

Nociceptor

A receptor that responds to pain stimuli.

Thermoreceptor

A receptor that detects changes in temperature.

Mechanoreceptors

Respond to mechanical pressure or distortion (e.g., touch, vibration).

Tactile (Merkel) Discs

Detect light touch and texture.

Hair Root Plexus

Responds to hair movement.

Tactile Corpuscles

Detect light touch.

Pacinian (Lamellated) Corpuscles

Detect deep pressure and vibration.

Ruffini (Bulbous) Corpuscles

Detect skin stretch and sustained pressure.

Two-Point Discrimination Test

Measures receptor field size—smaller fields = more precise discrimination.

Fingertips

Body part typically having the smallest distance for two-point discrimination.

Tactile Localization Test

Measures the brain's ability to identify where the skin is touched.

Temperature Adaptation

Occurs because thermoreceptors stop firing as the body adapts to constant stimuli.

Olfactory Epithelium Location

Located in the roof of the nasal cavity.

Olfactory Neuron Function

Detects odor molecules.

Bowman's Gland

Secretes mucus to help dissolve odorants.

Olfactory Adaptation

Reduced sensitivity to a smell after continuous exposure.

Types of Papillae

Circumvallate (Bitter), Fungiform (Sweet & Salty), Filiform (Texture, no taste buds), Foliate (Sour).

Five Primary Taste Sensations

Sweet, sour, salty, bitter, umami.

Taste Interaction with Dry Tongue

Tastants need to dissolve in saliva to interact with taste receptors.