ANS physiology Flashcards
(21 cards)
ANS nerves can be divided into ____ and ____ based on neurotransmitter released.
1) Cholinergic
2) Adrenergic
Nerve that releases acetylcholine is known as:
Cholinergic
Acetylcholine is broken down:
very rapidly
Enzyme that breaks acetylcholine down:
acetylcholinesterase
How long do the effects of cholinergic cells last and why?
Short-lasting because acetylcholine is broken down quickly
Neurons that release norepinephrine are:
Adrenergic
Most common type of adrenergic cell:
Postganglionic neurons of the sympathetic division
Norepinephrine is broken down:
Slowly
Why does norepinephrine take longer to break down?
A series of enzymes are required to fully break it down
How long do the effects of Adrenergic cells last and why?
Longer than cholnergic cells because of the amount of time it takes to break norepinephrine down
Effects of norepinephrine:
Depend on the type of receptor present in effector tissues
Sympathetic division of nervous system
Speed up the activity of effectors that spend energy and slow the activity of effectors that acquire energy
What type of response does the sympathetic division prompt?
“fight or flight” responses
List the fight or flight responses (10)
1) cause pupil to dilate
2) Dilate bronchial tubes
3) Dilate blood vessels of heart and lungs
4) Increase heart contraction speed and force
5) Increase blood pressure
6) Restricts blood flow to digestive system
7) Decrease action of digestive glands
8) Increase blood glucose level
9) Dilate blood flow to skeletal muscle
10) Increase action of adrenal glands
Why does the sympathetic division restrict blood flow to the digestive system?
Diverts blood elsewhere
Why do blood glucose levels increase during fight or flight responses?
to allow an ample supply of energy
What hormone do the adrenal glands release?
Epinephrine
What does epinephrine cause?
Makes receptors more sensitive to norepinephrine which enhances sympathetic effects
Parasympathetic division
Increases the action of tissues that acquire energy and decreases the action of tissues that spend energy
What does the parasympathetic division cause?
Restores tissues to normal
Since acetylcholine is broken down rapidly:
The body can shift to sympathetic stimulation quickly
