ch 16 Flashcards
somatic nervous systems
operates under conscious control
seldom affects long term survival
sns controls skeletal muscles
autonomic nervous system
operates without conscious instruction
ans controls visceral effectors
coordinates system functions
—- cardiovascular, respiratory, digestive, urinary, reproductive
enteric nervous system
brains of gut
extends most of length of gastrointestinal tract and found within walls of gi tract, pancreas, and gall bladder
thoracolumbar division vs craniosacral division
thoracolumbar aka sympathetic division: between T1 and L2; increases alertness, metabolic rate, and muscular abilities
craniosacral division aka parasympathetic division; 4 cranial nerves associated and between S2-S4; reduces metabolic rate and promotes digestion
sympathetic division
kicks in only during exertion, stress, or emergency
fight or flight
preganglionic fibers are short
postganglionic fibers are long
exception: adrenal medullae
heightened mental alertness, increases metabolic rate, reduced digestive and urinary function
parasympathetic division
; controls during resting conditions
rest and digest
preganglionic fibers are long
postganglionic fibers are short
stimulates visceral activity, conserves energy and promotes sedentary activities
constrict pupils, secretion by digestive glands, secretion of hormones, contraction of urinary bladder, reduction in heart rate.