chapter 3 vocab Flashcards
dendrites
parts of a neuron that are specialized to receive information
myelin sheath
an insulating layer that forms around nerves, including the brain and spinal cord, made up of protein and fatty substances, allows electrical impulses to transmit quickly and efficiently along the nerve cells
action potential
occurs when a neuron sends information down an axon, away from the cell body.
refractory period
a resting pause when the neuron pumps the positively charged sodium ions back outside
Agonist
a drug that binds to the receptor, producing similar response to the intended chemical receptor
Reuptake
a process in which neurotransmitters are sponged up from the synaptic cleft by the presynaptic membrane, reabsorbs
Axon
a long, thin fiber that transmits signals away from the soma and to other neurons or to muscles or glands
all-or-none response
either the neuron fire or it doesn’t, and its action potentials are all the same size
Endorphins
internally produced chemicals in your brain when your body feels pain or stress, produced to help relieve pain, reduce stress, and improve mood
Acetylcholine
every move you make depends on this, also contributed to attention, arousal, and memory
Interneuron
neurons interconnected by synapses to carry out a specific function when activated
Neurotransmitter
chemicals that transmit information from one neuron to another
Threshold
if excitatory signals (minus inhibitory signals) exceed a minimum intensity (threshold), combined signals trigger an action potential
Antagonist
a substance that interferes with or inhibits the physiological action of another, blocks neurotransmitters’ functions
Soma
cell body, contains the cell nucleus and much of the chemical machinery common to most cells
axon terminals
small knobs at the end of axons that secrete chemicals called neurotransmitters
Synapse
a junction where information is transmitted from one neuron to another, points where neurons interconnect
central nervous system
the brain and spinal cord
sympathetic nervous system
network of nerves that helps your body activate “fight or flight” response, activity increases when you stressed, in danger, or physical activity
Hormones
travel through the bloodstream and affect other tissues, including the brain, influence interest in sex, food, and aggression