75 terms

brain and behavior mid term

the insulating material which covers many axons is called
myelin sheath
which of the following describes selective permeability
only certain molecules are allowed to cross the membrane freely
afferent neurons carry impulses toward
muscles, glands and the central nervous system
the membrane of a neuron is specialized to
control the exchange of chemicals between inside and outside the cell
glial cells serves as which of the following functions
create myelin sheath, insulate axon and enable the the action potential to travel more quickly down the axon
neurotransmitters are released by which one of these structures
terminal bulbs
neurons are basic units of the nervous system, These cells are designed to be sustained through the process of receiving life support supplies and nutrients through transport systems. Whereas oxygen and water pass through the cell membrane through_____________ transport, other critical substance such as vitamins pass through the cell membrane through ___________transport system
an impulse travels down the cell from the soma to the ________through the terminal buttons
tourett syndrome represents a disorder of both_____________ neurons, or neurons sending impulses to the basal ganglia and _________ neurons, or cells carrying impulses away for the basal ganglia
afferent; efferent
a neuron may have many braches of __________but will have only one _______
dendrite; axon
which of the following is not preformed by neuroglia
producing action potentials
the blood brain barrier enables limited passages of materials across the membranes of a brains capillaries. THis passage may occur via both active and passive transport. Small molecules that can dissolve in fatty membranes are able to cross passively. an example of one these substances is
carbon dioxide and oxygen
when the neuronal membrane is at the rest, the potassium channels:
permit potassium ions to pass slowly
the__________is defined as the difference in the electrical charge between the inside and the axon membrane
membrane potential
the sodium potassium pump transports three_______ions out of the cell while drawing in two_____ions into it
the concentration gradient refers to
the difference in distributions of various ions between the inside and the outside of the membrane
which of the following is true of ion distribution across the neural membrane when the cell is at resting potential
sodium ions are highly concentrated outside the cell
for the cell to become hyperpolarized what need to happen
there has to be an increase in the negative charge internal to the cell
the decrease in the negative charge is
the actions potential of a neuron depends mostly on what movement of ions
sodium ions entering the cell
the concentration gradient for potassium tends to
push potassium out of the cell
the electrical gradient for sodium tends to
pull sodium into the cell
when a neuron reaches the threshold for depolarization
the membrane becomes highly permeable to sodium ions for a brief time
sodium channels in the cell membrane are
voltage sensitive or activated
reverse polarity
increased positive charge internal rather than external aka depolarization
action potentials are
all or none
refractory period
happens immediately after an action potential, where it resists production of another action potential
what happens during a refractory period
sodium channels are closed and potassium channels are traveling out of the cell
the strength of the potential
remains the same
graded potentials are to_________ as actions potentials are to_________
intensity of stimulus; all or none
temporal summation
repeated impulses over a brief period are accumulated
the firing of the postsynaptic neuron relies upon
graded potentials
sodium, depolarization
hyperpolarization, chloride
usually a _________ at the synapse will not be sufficient to create the threshold of excitation
single transmission
spatial summation
means that several inputs converge onto the post synaptic from different locations
neurons create chemicals that serve as
neurotransmitters are synthesized in
terminal vesicles
more than _______ substancces have been identified as NTS
when an actions potential reaches the vesicles the chemical is released
into the synaptic cleft
the chemicals crosses the celft and
attaches to receptor cites on the post synaptic neuron
the second messengers communicates to areas
within the cell
a metabotropic synapse by way of its second messenger
can influence activity in much or all or the post synaptic cell
ionotropic effects
may depolarize or hyperpolarize the postsynaptic membrane
exocytosis is the process by which neurotransmitters are
excerted into the synpatic cleft
which of the following characterizes the ionotropic effects
rapid, long lasting
the basic building blocks for the majority of neurotransmitter are
amino acids
neuropeptides synthesis is to the ________ as other neurotransmitter are to the ___________
soma; axon terminals
which of the following is more typical of a metabotropic effect rather than an ionotropic effect
produces long lasting effects on the post synaptic cell
first messengers are capable of directly __________or ________the post synaptic cell membrane. These ___________effects impact a small area of the postsynaptic cell
depolarize; hyperpolarize; iontropic
the diffusion of a neurotransmitters across the synaptic cleft is a
chemical process
what happens when a neurotransmitter is released by a presynaptic neuron
the neurotransmiter diffuses across the cleft the neurotransmitters undergoes a process of exocytosis
at ionotropic synapses the cell that recives the chemical message
is the presynaptic cell
the only area of the cerebral cortex known to receive input from all sensory modalities is the
frontal lobe
when the post synaptic cells depolarizes ______ ions enter the cell
the central sulcus separates the
frontal and the partial
reuptake is an alternative to which other process
metabolism of neurotransmitters
the presynaptic terminal ordinarily reabsorbs released neurotransmitters through a protein called
a transporter protein
autoreceptors monitor the
amount of neurotransmitters released and are metabotropic receptors
someone who suddenly loses the ability to identify objets by feeling them has probably suffered damange to what area of the cerebral cortex
parietal lobe
chemicals within the body and brain may serve as both neurotransmitters and hormones. Neurotransmitters systems may activate IPSP or EPSP potentials. Hormones activate ___________ and create__________
second messengers; metabotropic
which lobe seems espcially involved in the comprehension of spoken language
temporal lobe
neurons within the cortext are organized in
6 laminae and columnar fashion
the precentral gyrus is also knows as the _________________ and is located in the________________ lobe
primary motor area; frontal
pons, medulla, cerebellum (older)
newer superior colliculus, inferior colliculus, tectum, tegmentum, substantia nigra
most anterior cortical lobes, thalamus,hypoothalmus, pituitary gland, basal ganglia, ventricels, hippocampus, contralateral control
hindbrain controls
life support refelexes
midbrain controls
eye movements aka mesencephalon
pathways for sensory information to communicate
feeding, drinking, temp. sex
basal ganglia
intergated movements-speech
spinal fluid
what structures compose the limbic system
thalmus, hypothalmus, amygdala