Unit 1 Flashcards
Significance of Nervous system
controls coordination, association. and integration of body responses to internal and external stimui
The cost of such high specialization means little ability to store oxygen or glucose plus little mitotic ability
Neuroanatomy
study of structure
Neurophysiology
study of function
Neuropathology
study of disease
Neuropharmacology
study of how drugs affect
Chiropractic
manipulates skeletal and nervous systems
Synonym for brain
encephalon (CNS)
synonym for spinal cord
medulla spinalis (CNS)
Cranial nerves pairs?
12 (PNS)
Spinal nerve pairs?
31 (PNS)
ganglia definition
groups of cell bodies in the PNS
Somatic component of Nervous system
innervates skeletal muscles
often called voluntary component
includes efferent (away from CNS) and afferent (towards CNS) nerves fibers
involves both CNS and PNS
Acetylcholine
chemical released by somatic axon endings (cholinergic)
appears to only have an excitatory function
Autonomic/Visceral component of nervous system
innervates glands, smooth, and cardiac muscle
no conscious control over said structures
involves both CNS and PNS
efferent fibers receive emphasis and are the only ones divided into sympathetic and parasympathetic subdivisions
Parasympathetic subdivision
have neurons in both CNS and PNS and only innervate Cranial nerves III, VII, IX, and X, as well sacral nerves 2-4 (craniosacral)
two efferents are needed to reach glands or muscle.
Preganglionic (parasympathetic)
first neuron is long and releases acetylcholine
Postganglionic (parasympathetic)
second neuron is short and goes to target tissue and releases acetylcholine
Sympathetic subdivision
visceral component (fight or flight)
located in CNS and PNS but PNS efferent fibers are T1-L2
again two neurons used in getting to glands or muscle cells
preganglionic (sympathetic)
shorter and releases ACH
postganglionic (sympathetic)
longer and releases norepinephrine instead (adrengeric)
Example effects of parasympathetic
slows heart rate/ speeds peristalsis/ constricts pupils/constricts respiratory tree (keep in mind effects are opposite of sympathetic)
Example effects of sympathetic
speeds heart rate/ slows peristalsis/ dilates pupils/ dilates respiratory tree (keep in mind effects are opposite of parasympathetic)
sympathetic ratio
1:17 general and more widespread
parasympathetic ratio
1:2 thus response is more limited but more precise
