nervous system Flashcards
how does our nervous system communicate?
electrical impulses = body cells
what’s in the central nervous system?
brain and spinal chord
- they occupy the dorsal body cavity and act as the integrating and command centers of the nervous system
the central nervous system interprets….
sensory information
what is neuroglia?
glia (nerve glue)
they will support, insulate, and protect delicate neurons
do neuroglia transmit nerve impulses?
no
what is nurofibrils?
- found inside the cell body
- their function is to maintain cell shape
- the arm like processes very in length
microscopic 3-4 feet
longest neurofibrils is
reaching from lumbar region of the spine to the big toe
what are dendrites?
the neuron processes that convey incoming messages (electrical signals) towards the cell body
What do axons do?
neuron processes that generate nerve impulses and conduct them away from the cell body
what do the axon terminals contain?
neurotransmitters
what are efferent motor cells?
they carry impulses to the muscles and glands located in the CNS
what are interneurons association neurons?
they connect the motor and sensory neurons in neural pathways located in the CNS
what are multipolar neurons?
motor and association
based on the number of processes extending from the cell body
(several processes)
what are bipolar neurons?
neurons with two processes an axon and a dendrite
where are bipolar neurons found?
in some special sensory receptor cells of the eye and ear
what are unipolar neurons
they have a single process emerging from the cell body
where are unipolar neurons found?
in the Peripheral nervous system extending from the brain and the spinal cord
potassium is ( ) and Sodium is ()
positive inside , less positive outside
what happens when the neuron is adequately stimulated?
the “sodium gates” in the membrane open
because of diffusion sodium in higher concentration outside the cell will diffuse quickly into the neuron
what is depolarization?
the inward rush of Na+ changes the polarity of the neurons membrane
during polarization the inside is now ( ) and outside is more ()
positive, less positive (negative)
what is repolarization?
restoring of electrical conditions
resting state
after repolarization what happens?
the sodium/potassium pump uses cell energy ATP to pump excess Na+ out of the cell and to bring K+ back into the cell
what is conductivity?
the travel of an impulse along one neuron to another neuron
what is an electrochemical event?
the transmission of an impulse
transmission down the neuron is ( ) with depolarization and repolarization
electrical
automatic reflexes are within the…
heart and glands
somatic reflexes include
all reflexes that stimulate the skeletal muscles
- pulling hand away from something hot
- all reflex arcs have a minimum of five elements
the three neuron reflex arc consists of the five elements
- receptor
- afferent neuron
- association neuron
- efferent neuron
- efferent
