Chapter 2: Biology and Psychology Flashcards
neuron
a specialized cell of the nervous system that receives and transmits messages.
glial cells
Cells that remove dead neurons and waste products from the nervous system, nourish and insulate neurons, form myelin, and play a role in neural transmission of messages.
Dendrites
Root-like structures attached to the cell body of a neuron, they receive impulses or incoming messages from other neurons and the surrounding environment of the neuron cell body.
axon
A long thin part of a neuron transmits impulses to other neurons from the bulb-shaped structures called axon terminals or terminal buttons.
myelin
a fatty substance that encases and insulates axons, facilitating transmission of neural impulses.
afferent neurons
neurons that transmit messages from sensory receptors to the spinal cord and brain; also called sensory neurons.
efferent neurons
neurons that transmit messages from the brain or spinal cord to muscles and glands; also called motor neurons.
neural impulses
The electrochemical discharge of a nerve cell or neuron.
polarize
to ready a neuron for firing by creating an internal negative charge in relation to the body fluid outside the cell membrane.
polarize
to ready a neuron for firing by creating an internal negative charge in relation to the body fluid outside the cell membrane.
resting potential
The electrical potential across the neural membrane when it is not responding to other neurons.
depolarize
Is to reduce the resting potential of a cell membrane from about 70 millivolts to zero.
action potential
The electrical impulse that provides the basis for the conduction of a neural impulse along the axon of a neuron.
all-or-none principle
The fact that a neuron fires an impulse of the same strength whenever its action potential is triggered.
refractory period
a phase following firing during which a neuron is less sensitive to messages from other neurons and will NOT fire.
synapse
A junction between the axon terminals of one neuron and the dendrites or cell body of another neuron.
neurotransmitters
chemical substances involved in the transmission of neural impulses from one neuron to another.
receptor site
a location on a dendrite of a receiving neuron tailored to receive a neurotransmitter.
acetylcholine (ACh)
a neurotransmitter that controls muscle contractions
Hippocampus
A structure of the brain that is involved in memory formation.
Dopamine
A neurotransmitter that affects the ability to receive pleasure, voluntary movement, learning, and memory, it is involved in Parkinson’s disease and appears to play a role in schizophrenia.
Norepinephrine
A neurotransmitter whose action is similar to that of the hormone epinephrine and that may play a role in depression.
serotonin
A neurotransmitter involved in emotional arousal and sleep; deficiencies of serotonin have been linked to eating disorders, alcoholism, depression, aggression, and insomnia.
Gamma-aminobutyric Acid (GABA)
An inhibitory neurotransmitter that apparently helps calm anxiety.
endorphins
Inhibitory neurotransmitters occur naturally in the brain and in the bloodstream and are similar to the narcotic morphine in their functions and effects.
nerves
centeral nervous system (CNS)
Peripheral Nervous System (PNS)
Somatic Nervous System (SNS)
Autonomic Nervous System (ANS)
Sympathetic Division
Parasympathetic Division
spinal Cord
