Peripheral Nervous System & Reflex Activity

These flashcards cover key concepts related to the Peripheral Nervous System and Reflex Activity, aiding in understanding the structure, function, and classifications involved.

Peripheral Nervous System (PNS)

Connects the central nervous system to the organs, limbs, and skin, carrying sensory and motor information.

Afferent Division

Part of the PNS that transmits sensory information to the central nervous system.

Efferent Division

Part of the PNS responsible for carrying motor commands from the central nervous system to the body.

Somatic Nervous System

Controls voluntary movements via skeletal muscles.

Autonomic Nervous System

Regulates involuntary body functions such as heartbeat and breathing.

Sensory Receptors

Specialized structures that detect stimuli, classified by stimulus type, location, and structure.

Nerve Plexus

A network of intersecting nerves that provides a level of organization and redundancy in nerve supply.

Reflex Arc

The neural pathway involved in a reflex action, consisting of a receptor, sensory neuron, integrating center, motor neuron, and effector.

Innate Reflexes

Reflexes that are genetically determined and do not require learning.

Acquired Reflexes

Reflexes that are learned from experience and are not genetically programmed.

Monosynaptic Reflex

A reflex involving a single synapse between a sensory neuron and a motor neuron.

Polysynaptic Reflex

A reflex that involves multiple synapses, often including interneurons.

Cranial Nerves

Twelve pairs of nerves that innervate various regions of the head and neck, each with specific functions.

Dermatomes

Areas of skin supplied by a single spinal nerve root, important in sensory perception.

Phrenic Nerve

A nerve that originates from the cervical plexus and is crucial for diaphragm control in breathing.

Sciatic Nerve

The largest nerve in the body that innervates the lower limb.

Stretch Reflex

A monosynaptic reflex that helps control muscle length by triggering contraction in response to stretching.

Withdrawal Reflex

A polysynaptic reflex that protects the body from harmful stimuli by withdrawing a body part.

Descending Tracts

Nerve pathways that carry motor signals from the brain down to the spinal cord.

Ascending Tracts

Nerve pathways that carry sensory information from the body to the brain.