ANS Flashcards
the maintenance of an optimal internal environment, including body temp and chemical composition of tissues and fluids
Homeostasis
What plays a big role in controlling homeostasis?
controlling blood flow
What receptor types are included in autonomic sensation?
- Mechanoreceptors -Stretch/ Pressure (bladder full, GI tract, BP)
- Nociceptors - Pain
- Thermoreceptors - Temperature (measures external and internal temp, to adjust accordingly)
- Chemoreceptors - Oxygen, pH
Where are chemoreceptors of the ANS located and what do they measure?
- Carotid and aortic bodies for O2
- Medulla for pH levels
- Hypothalamus for glucose and electrolyte levels
What do the nociceptors in the ANS respond to? where are they located?
- Stretch
- Ischemia
- walls of arteries and internal viscera
What do the mechanoreceptors of the ANS respond to? where are they located?
- Pressure - aortic artery, carotid sinus (blood pressure)
2. stretch - bladder, veins
Where are the thermoreceptors of the ANS located? what do they respond to?
- hypothalamus - internal temperature
2. skin - outside temperature
How does ANS information get into the CNS?
- Dorsal roots - travel with the normal nerves
2. Cranial nerve - Taste information (7, 9 and 10) and visceral sensation (9 and 10)
Where are visceral control areas? what do they control?
- Medulla- HR, respiration, blood vessels (vasodilation)
2. Pons - respiratin
Where are visceral modulatory areas? what do they control?
- Hypothalamus - overal control of homeostaces (cardiorespiratory, metabolic, water reabsorption, and digestion)
- Thalamus - relay station that gives the info to the limbic cortex (connection btwn visceral fxns and emotions/ psychological state)
- Limbic system - can produce autonomic responses (anxiety, blushing with embarrassment, crying)
How many neurons are included in the efferent motor system of the PNS?
two;
- CNS (preganglionic)
- PNS (postganglionic)
What is the preganglionic neurotransmitter in the ANS? what is the receptor it binds to?
Acytlcholine; nicotinic receptors
What neurotransmitter do sympathetic postgangliongic neurons that go to sweat glands and some blood vessels produce? what do the receptors bind to?
Acytlcholine; muscarinic receptors
What neurotransmitter do most sympathetic postganglionic neurons produce? what are its target receptors?
NE; Alpha and Beta receptors
What does the adrenal medulla release? What receptors?
primarily Epinephrine
secondarily NE
- alpha and beta receptors
What neurotransmitter parasympathetic postganglionic neurons produce? what are its target receptors?
ACh; Muscarinic receptors
What neurotransmitter somatic neurons produce? what are its target receptors?
ACh; nicotinic receptors
-no pre/post ganglionic neurons in somatic NS
What spinal levels are pregagnlionic neurons located?
T1-L2
What are the targets of the ANS?
- GI tract
- Skin of extremities and face (sweat glands, hair sticking up, oil glands) - Only supplied by sympathetic fxn, no parasympathetic fxn
What does the adrenergic (sympathetic) do to blood vessels? cholinergic?
- vasoconstriction
- cholinergic
What are the functions of the sympathetic NS at the heart, lungs, and GI tract?
- increase HR and contractility (Beta 1)
- Bronchodilation (beta 2)
- Slows down GI tract
What are the ganglia above T1 (in the neck region)?
- Superior cervical ganglion
- Middle cervical ganglion
- Stellate ganglion (inferior cervical ganglion)
- Sympathetic fxns: control heart (BV), lungs, skin in the face (BV, sweating), pupil dilation, 1 muscle that opens the eye, thick saliva
What regulates body temp in the sympathetic nervous system?
- Increase metabolic rate (warms)
- Decreased blood flow to the skin (warms)
- Sweating (cools)
- Erection of hair (warms)
What is another name for Parasympathetic NS? sympathetic?
Cranialsacral (brainstem, S2,S4); thoracolumbar
