Autonomic Nervous System Flashcards
- name implies that visceral innervation operates involuntarily on its own (in contrast to the voluntary control characteristic of somatic innervation of skeletal muscle)
Autonomic
- means self-rule/self-govern; from the Greek: auto = ____; nomos = ____
self
rule
also known as chemical messengers, are endogenous chemicals that enable neurotransmission. They transmit signals across a chemical synapse, such as a neuromuscular junction, from one neuron (nerve cell) to another “target” neuron, muscle cell, or gland cell.
Neurotransmitters
a nerve cell cluster or a group of nerve cell bodies located in the autonomic nervous system
Ganglion
branching network of intersecting nerves
Plexus
a specialized cell transmitting nerve impulses; a nerve cell.
Neuron
- The _______ ____ and ______ _____ are located within the vertebral canal of the vertebral column. Dorsal and ventral spinal roots unite to form a spinal nerve (bilaterally).
spinal cord
spinal roots
is enveloped by connective tissue (epineurium, perineurium, & endoneurium)
Spinal Nerve
composed of afferent (sensory) axons; the site of a spinal ganglion
dorsal root
composed of efferent axons that innervate muscle & gland
ventral root
Divides into four primary branches:
Ømeningeal branch
Øramus communicans
Øventral branch
Ødorsal branch
*four primary branches:
small; sensory to meninges
Ømeningeal branch
*four primary branches:
connects to sympathetic trunk & innervates viscera
Øramus communicans
*four primary branches:
largest branch; hypaxial mm. & lateral and ventral cutaneous nn.
Øventral branch
*four primary branches:
medial and lateral branches; epaxial mm and dorsal cutaneous nn.
dorsal branch
*Fiber types
axons associated with receptors and unipolar cell bodies in spinal ganglia
Afferent (sensory)
*Fiber types, Afferent (sensory)
receptors in skin & muscles, tendons, joints
- General Somatic Afferent (GSA):
*Fiber types, Afferent (sensory)
receptors in viscera
- General Visceral Afferent (GVA):
*Fiber types
axons that innervate muscle & gland; cell bodies are located in the spinal cord (or in some cases autonomic ganglia)
Efferent (motor)
*Fiber types, Efferent (motor)
innervates skeletal muscle
Somatic Efferent (SE):
*Fiber types, Efferent (motor)
innervates cardiac m., smooth m., & gland
Visceral Efferent (VE):
- Also known as the GENERAL VISCERAL EFFERENT (GVE)
- Portion of the nervous system concerned with the motor innervations of smooth muscle, cardiac muscle and glands.
Autonomic Nervous System (ANS)
GVE Pathaway involves two neurons
preganglionic neuron
postganglionic neuron
*GVE Pathaway two neurons
cell body located in CNS; axon synapses in an autonomic ganglia
preganglionic neuron
*GVE Pathaway two neurons
cell body in an autonomic ganglion; axon \ innervates smooth muscle, cardiac muscle or gland; Ordinarily occur in clusters referred to as ganglion.
postganglionic neuron
Autonomic Nervous System of PNS (?)
involuntary
Somatic Nervous System of PNS (?)
voluntary
- pathways that innervate smooth muscle, cardiac muscle, and glands involve two neurons and a synapse within an autonomic ganglion.
Two-neuron pathways
*Classification of Autonomic Ganglia
Are more or less segmentally distributed along the paired sympathetic chains which in turn lie along the ventral sides of the heads of the ribs
Vertebral ganglia