ANS Flashcards
Are visceral motor functions easily controlled by the conscious will?
No. Like nausea, sweating, and full bladder
The ANS is a system of _____ neurons
motor
Regulates ______ visceral functions such as…..
unconscious
- heart rate
- blood pressure
- digestion
- urination
The ANS innervates…..
smooth muscle
cardiac muscle
glands
Somatic motor innervation
one motor neuron extends from CNS to skeletal muscle
-myelinated axons
Autonomic innervation
two motor neurons
-slower conduction
preganglionic neuron- spinal cord and brain
postganglionic neuron- autonomic motor pathway
Divisions of the ANS
sympathetic and parasympathetic
Sympathetic division
responds to dangerous or exciting situations
-increased HR and breathing
-widened pupils
nonessential functions are inhibited
What organs have only sympathetic innervation?
- sweat glands
- adrenal medulla
- arrector pili
- blood vessels
What part of the brain elicits a terror induced systemic response?
midbrain
Parasympathetic division
conserves body energy and directs vital activities
-dominates sympathetic impulses
SLUDD
-salivation, lacrimation, urination, digestion, defecation
What are the 3 decreases with the parasympathetic division?
HR
diameter of airways
diameter of pupils
What happens when there is no escape route or no way to win?
- massive activation of parasympathetic division
- loss of control over urination and defecation
Where do sympathetic and parasympathetic responses arise from?
S- thoracolumbar region
PS- craniosacral region
Length of postganglionic neurons in sympathetic and parasympathetic divisions?
S- long
PS- short
Axon branches of sympathetic and parasympathetic divisions?
S- highly branched
PS- few (localized effect)
Role of adrenal medulla?
secretes norepinephrine and epinephrine
-surge of adrenaline
Spinal cord controls….
urination, defecation, erection
Medulla oblongata controls…
HR, digestion, blood vessel diameter
Midbrain is responsible for….
sympathetic fear response
Hypothalamus is the…..
main integration centre of ANS
Amygdala is the …..
main limbic region for emotions
Cerebral cortex controls….
thoughts and emotions
Insula
receives general sensory input from thoracic and abdominal viscera and gustation via thalamus
