Ch. 10 Nervous System Flashcards
What is the function of the nervous system?
to coordinate and control all bodily systems
What are the 4 major structures of the nervous system?
- nerves
- brain
- spinal cord
- sensory organs (eyes, ears, nose, skin, tongue)
What are the two primary parts of the nervous system?
- central nervous system (CNS)
2. peripheral nervous system (PNS)
What does the CNS consist of? What is it’s function?
Brain and spinal chord
to receive and process info, and to regulate all bodily activities
What does the PNS consist of? What is it’s function?
12 pairs of cranial nerves extending from the brain and the 31 pairs of peripheral spinal nerves extending outward from the spinal cord.
to transmit nerve signals to, and from, the CNS.
one or more bundles of neurons that connect the brain and the spinal cord with other parts of the body
nerve
bundle or group of nerve fibers located within the brain or spinal cord
tract
carry nerve impulses toward the brain
ascending nerve tracts
carry nerve impulses away from the brain
descending nerve tracts
a nerve center made up of a cluster of nerve cell bodies outside the central nervous system
ganglion
means the supply of nerves to a specific body part
innervation
a network of intersecting spinal nerves
plexus
sites in the sensory organs that receive external stimulation
receptors
anything that activates a nerve and causes an impulse
stimulus
an automatic, involuntary response to some change, either inside or outside the body
reflex
the basic cells of the nervous system that allow different parts of the body t communicate with each other
neurons
What are the three types of neurons?
- afferent neurons
- connecting neurons
- efferent neurons
What do the afferent neurons do?
known as the sensory neurons, these neurons emerge from sensory organs and the skin to carry the impulses from the sensory organs toward the brain and spinal cord
What do the connecting neurons do?
aka associative neurons, they link sensory and motor neurons
What do the efferent neurons do?
aka motor neurons, they carry impulses away from the brain and spinal cord toward the muscles and glands
the root-like processes of the neuron that receives impulses and conducts them to the cell body
dendrites
a process of the neuron that extends away from the cell body and conducts impulses away from the nerve cell
axon
the branching fibers at the end of the axon that lead the nervous impulse from the axon to the synapse
terminal end fibers
the space btw two neurons or btw a neuron and a receptor organ
synapse