EXAM 4: Chapter 14 The Nervous System III: The Peripheral Nervous System (PNS)単語カード | Quizlet

peripheral nervous system (PNS)

nervous system structures outside of brain and spinal cord; its nerves thread through almost every part of the body

nerve

a cord-like organ in the PNS consisting of many axons (nerve fibers) arranged in parallel bundles (fascicles)

epineurium - perioneurium - endoneurium

What are the 3 layers that cover a nerve? from external to internal?

Carry both sensory and motor axons

MOST nerves are mixed, meaning what?

cranial nerves and spinal nerves

The CNS is connected to the PNS via what?

sensory (afferent) division

and

motor (efferent) division

The PNS is subdivided into what two divisions?

somatic nervous system (voluntary)

and

autonomic nervous system (involuntary)

The motor division > PNS is divided into what 2 categories?

sympathetic nervous system

and

parasympathetic nervous system

The autonomic nervous system > motor division > PNS is divided into what 2 categories?

parasympathetic nervous system

which division of the autonomic nervous system is:

craniosacral - rest and digest or rest and repose

sympathetic nervous system

which division of the autonomic nervous system is:

thoracolumbair - fight or flight

peripheral sensory receptors

pick up sensory stimuli (environmental changes_ from inside and outside of the body, then initiates impulses in sensory axons

dendritic endings of sensory neurons

and

receptor cells

What are two main categories of peripheral sensory receptors?

peripheral motor endings

axons terminals of motor neurons that innervate effectors (muscles and glands)

neuromuscular junction

motor end plates; one junction associated with each muscle fiber

Acetylcholine

a neurotransmitter (brain chemical) that diffuses across the synaptic cleft and binds to receptors of the sarcolemma

induces impulses - signals the muscle cell to contract

motor unit

a motor neuron innervating muscle fibers

ganglion

A cluster of nerve cell bodies, often of similar function, located in the PNS.

dorsal root ganglion

PNS ganglion containing the cell bodies of SENSORY neurons

white ramus

which ramus contains myelinated preganglionic axons

gray ramus

which ramus contains axons that innervate glands and smooth muscles in the body wall or limbs back to spinal nerve

dorsal root

contains sensory fibers and originates from the dorsal root ganglia

ventral root

contains motor fibers and originates from the anterior/ventral horn of the spinal cord

musculocutaneous nerve, median nerve and ulnar nerve

What are the nerves of the brachial plexus from lateral to medial?

median nerve

nerve formed by the lateral and medial cords

musculocutaneous nerve

nerve formed by just the lateral cord

ulnar nerve

nerve formed by the medial cord

radial nerve

formed by the posterior cord

radial nerve

Which nerve of the brachial plexus is involved in Saturday Night Palsy?

sciatic nerve

thicket and longest nerve in the body

innervates all of the lower limb except anterior and medial thigh regions

composed of 2 nerves, wrapped in common sheath

(tibial nerve & common fibular (peroneal) nerve)