Nervous System Flashcards
The master controlling and communicating system of the body.
Nervous system
Gathered information
Sensory input
Processes and interprets the sensory input and makes decisions about what should be done at each moment.
Integration
Consists of the brain and spinal cord.
Central nervous system
The part of the nervous system outside the CNS, consists of the nerves that extend from the brain and spinal cord.
Peripheral nervous system
Consists of nerve fibers that convey impulses to the CNS from sensory receptors located in various places.
Afferent
Carries impulses from the CNS to effector organs, the muscles and glands.
Efferent
Allows us to consciously, or voluntarily, control our skeletal muscles.
Somatic nervous system
Regulates events that are automatic, or involuntary, such as the activity of smooth and cardiac muscles and glands..
Autonomic nervous system
When supporting cells in the CNS are “glued” together.
Neuroglia
Abundant star-shaped cells that account for nearly half of the neural tissue.
Astrocytes
Spider-like phagocytes that dispose of debris, including dead brain cells and bacteria.
Microglia
These glial cells line the cavities of the brain and the spinal cord.
Ependymal cells
Glia that wrap their flat extensions tightly around the nerve fibers, producing fatty insulating coverings called myelin sheaths.
Oligodendrocytes
Form the myelin sheaths around nerve fibers that are found in the PNS.
Schwann cells
Protective, cushioning cells.
Satellite cells
Also called nerve cells, are highly specialized to transmit messages from one part of the body to another.
Neurons
Neuron processes that convey incoming messages toward the cell body.
Dendrites
Like dendrites, but the nerve impulses conduct them away from the cell body.
Axon
Cone-like region of the cell body.
Axon hillock
An occasional axon gives off a collateral branch along its length, but all axons branch profusely at their terminal end, forming hundreds to thousands of these
Axon terminals
Terminals that contain hundreds of tiny vesicles, or membranous sacs, that contain these chemicals.
Neurotransmitters
Long nerve fibers are covered with this whitish, fatty material.
Myelin
Tight coil of wrapped membranes
Myelin sheath
