Neural Control of Exercising Muscle Flashcards
(99 cards)
What is the nervous system divided into?
CNS (Central) and PNS (Peripheral)
What is the CNS and PNS composed of?
Brain/Spinal Cord & PNS composed of sensory and motor nerves
What are sensory and motor nerves also known as?
afferent and efferent
What are sensory nerves?
informing the CNS about what is going on within and outside the body (incoming)
What are motor nerves?
responsible for sending information from the CNS to the various tissues, organs, and systems of the body in response to the signals coming in from the sensory division (outgoing)
What are the motor nerves composed of?
autonomic and somatic nervous system; voluntary to skeletal muscles; involuntary to internal organs and bodily functions
What is the autonomic nervous system further divided into?
sympathetic and parasympathetic nervous system
What is the neuron and what three regions is it composed of?
neuron is the basic unit of nervous system; cell body, dendrites, and axon
Describe the cell body.
it contains a nucleus; cell processes radiate outward
Describe dendrites.
receives cell processes; carries impulse toward the cell body
Describe the axon.
sends cell processes by starting at the axon hillock; has end branches, terminals, and nuerotransmitters
Where does communication occur with the electrical signal?
between the periphery and brain
How is the electrical signal generated, propagated, and then transmitted?
stimulus; down an axon; to the next cell in line
What is the difference in electrical charges between the outside and inside of the cell?
-70 mV
Why is there a difference in electrical charges between the outside/inside the cell?
uneven separation of charged ions; polarized
Why is it -70 mV?
There is a higher concentration of sodium cells outside the cell and medium # of potassium cells; more negative inside to outside
Can Na+ ions enter the channel?
They’re unable to, but channels are closed.
Are K+ channels open?
Yes; K+ ions leave the cell.
Describe the pathway of how the neuron allows nerve impulses travel:
dendrites > cell body > axon hillock > axon > axon terminal
What are axon terminal (synaptic knobs) filled with?
neurotransmitters
When does depolarization occur?
when the inside of the cell becomes less negative (-70 mV to 0 mV)
Why does depolarization occur?
as more positively charged sodium channels open, the Na+ ions enter the cell
Which is required for nerve impulses to arise and travel?
depolarization
When does hyperpolarization occur?
when the inside of the cell becomes more negative (-70 mV to -90 mV), more K+ channels open, allowing K+ to leave the cell