peripheral nervous system Flashcards
1
Q
what does the peripheral nervous system do?
A
- links brain and spinal cord to rest of body
- sends sensory impulses to the CNS
- transmits motor impulses from CNS to effectors
- divided into somatic (voluntary) and autonomic (involuntary) systems
2
Q
what is the somatic system?
A
- voluntary control
- more spinal nerves than cranial nerves are all myelinated
3
Q
what are the cranial nerves of somatic system?
A
- mostly associated with functions of the head, neck and face
- vagus nerve is cranial nerve that connects to internal organs
4
Q
What is the autonomic system?
A
- involuntary control
- nerves inhibit or stimulate glands, cardiac muscle or smooth muscle
- maintains homeostasis
- controlled mainly by hypothalamus and medulla oblongata
- divided into sympathetic and parasympathetic
5
Q
describe the spinal nerves of the somatic system
A
- 31 pairs
- each nerve contains sensory and motor neurons
- each nerve services the area of the body where it is found
6
Q
what is the sympathetic nervous system?
A
- responsible for fight or flight response
- sympathetic neurons release the neurotransmitter norepinephrine
- also signal adrenal glands to release epinephrine and norepinephrine
7
Q
what is norepinephrine?
A
- excitatory effect on target muscles
- acts with epinephrine to trigger stress response
8
Q
what is the stress response?
A
- increases heart rate and blood pressure
- diverts blood to skeletal muscles
- slows digestion
9
Q
describe the parasympathetic nervous system
A
- active when body is at rest
- restores and conserves energy
- reverse effect of stress response
- main neurotransmitter involved in acetylcholine
10
Q
sympathetic and para sympathetic systems usually work to _______ one another (balance)
A
counteract
