PGS 101 Ch. 3
Terms
undefined, object
copy deck
- neurons
- individual cells in the nervous system that recieve, integrate, and transmit info
- soma
- (cell body) contains the cell nucleus and much of the chemical machinery common to most cells
- dendrites
- parts of a neuron that are specialized to receive information
- axon
- a long, thin fiber that transmits signals away from the soma to other neurons or to muscles or glands
- terminal buttons
- small knobs that secrete chemicals called neurotransmitters
- synapse
- a junction where info is transmitted from one neuron to another
- resting potential
- stable negtive charge when the cell of a neuron is inactive
- action potential
- a very brief shift in a neuron's electrical charge that travels along an axon
- absolute refractory period
- the minimum length of time after an action potential during which another action potential cannot begin
- synaptic cleft
- a microscopic gap between the terminal button of one neuron and the cell membrane of another neuron
- neurotransmitters
- chemicals that transmit info from one neruon to another
- postsynaptic ptotential (PSP)
- a voltage change at a receptor site on a postsynaptic cell membrane
- reuptake
- a process in which neurotransmitters are sponged up from the synaptic cleft by the presynaptic membrane
- agonist
- chemical that mimics the action of a neurotransmitter
- antagonist
- a chemical that opposes the action of a neurotransmitter
- endorphins
- internally produced chemicals that resemble opiates in structure and effects
- peripheral nervous system
- made up of all thsoe nerves that lie outside the brain and spinal cord
- somatic nervous system
- made up of nerves that connect to voluntary skeletal muscles and to sensory receptors
- afferent nerve fibers
- axons that carry info inward to the central nervous system from the periphery of the body
- efferent nerve fibers
- axons that carry info outward from the central nervous system to the periphery of the body
- autonomic nervous system (ANS)
- made up of nerves that connect to the heart, blood vessels, smooth muscles, and glands
- central nervous system (CNS)
- consists of the brain and the spinal cord
- hindbrain
- includes teh cerebellum and two structures found in the lower part of the brainstem: the medulla and the pons
- midbrain
- the segment of the brainstem that lies between the hindbrain and the forebrain
- forebrain
- largest and most complex region of the brain, encompassing a variety of structures, including the thalamus, hypothalamus, limbic system, and cerebrum
- thalamus
- structure in the forebrain through which all sensory info (except smell) must pass to get to the cerebral cortex
- hypothalamus
- a structure found near the base of the forebrain that is involved in the regulation of basic biological needs
- limbic system
- a loosely connected network of structures located roughly along the border between the cerebral cortex and deeper subcortical areas
- cerebral cortex
- the convoluted outer layer of the cerebrum
- cerebral hemispheres
- the right and left halves of the cerebrum
- corpus callosum
- the major structure that connects the two cerebral hemispheres
- split-brain surgery
- bundle of fibers that conects the cerebral hemispheres (the corpus callosum) is cut to reduce the severity of epileptic seizures