Biological Bases Flashcards
(30 cards)
neurons
individual cells in the nervous system that receive, integrate, and transmit information
axon
the extension of a neuron, ending in branching terminal fibers, through which messages pass to other neurons or to muscles or glands
soma
part of a neuron that contains its nucleus and other standard cellular structures
dendrites
The bushy, branching extensions of a neuron that receive messages.
action potential
a neural impulse; a brief electrical charge that travels down an axon
myelin sheath
a layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impules as the impulse hops from one node to the next
reuptake
a neurotransmitter’s reabsorption by the sending neuron
endorphins
“morphine within”–natural, opiatelike neurotransmitters linked to pain control and to pleasure
endocrine system
the body’s “slow” chemical communication system; a set of glands that secrete hormones into the bloodstream
pituitary gland
releases a great variety of hormones that fan out around the body, stimulating actions in the other endocrine glands
hormones
chemical messengers secreted by the endocrine system
neurotransmitters
Special brain chemicals that are responsible for movement, thinking, and emotions.
glutamate
-Major Excitatory Neurotransmitter
-Memory
Too much=overstimulates brain producing migraines/seizures
dopamine
-voluntary movement, learning, attention, emotion
MALFUNCTION
- Too little: can cause shakiness throughout the body, tremors, and decreased mobility–Parkinson’s
-Too much–hallucinations–Schizophrenia
acetycholine
- enables muscle action (movement) and is used by different neurons.
- Learning and memory
- Found in the connection between motor neurons and muscle fibers
MALFUNCTION: Alz–producing neurons deteriorate
norepinephrine
-autonomic nervous system: sleep and heart rate
- Sexual responsiveness
-control alertness
-arousal
-learning and memory
Malfuction
- too little; depressed moods, anxiety, high blood pressure
GABA
Major INHIBITORY neurotransmitter
-inhibitory–slows down system, linked to insomnia seizures, anxiety
Malfunction
-Too little: seizures, tremors, anxiety
serotonin
-Mood, hunger, sleep, dreaming, arousal, pain, aggression, sexual behavior, emotional state,
-Too little: depression (prozac too boost these levels)
Cerebral cortex
the intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body’s ultimate control and information-processing center
Corpus collosum
bridge of fibers passing information between the two cerebral hemispheres
Thalamus
relay center for cortex; handles incoming and outgoing signals
Hypothalamus
responsible for regulating basic biological needs: hunger, thirst, temperature control
Reticular formation
group of fibers that carry stimulation related to sleep and arousal through brainstem
Medulla
responsible for regulating largely unconscious functions such as breathing and circulation
