test one sample Qs Flashcards
(45 cards)
To measure temporal summation in single cells, researchers ___
record depolarizations of the postsynaptic neuron
. If all of a neuron’s dendrites or axons were contained within the spinal cord, it would be considered a(n) ____ neuron
intrinsic
The presynaptic terminal stores high concentrations of neurotransmitter molecules in ____.
vesicles
. Which type of glia builds myelin sheaths around axons in the periphery of the body?
schwann cells
. Which process indicates spatial summation?
present two or more weak stimuli at the same time
What ordinarily prevents extensor muscles from contracting at the same time as flexor muscles?
inhibitory synapses in the spinal cord
When a membrane is at rest, what attracts potassium ions to the inside of the cell?
an electrical gradient
vesicles are located ____
in presynaptic terminals
What is the function of the enzyme acetylcholinesterase?
it breaks acetylcholine down into components for recycling
. A drug that blocks the sodium gates of a neuron’s membrane will ____.
blocks the action potential
A normal, healthy animal never contracts the flexor muscles and the extensor muscles of the same leg at the same
time. Why not?
when the interneuron sends excitatory messages to one another, inhibitory messages go to the other
Neurons typically have one ____, but many ____
axon; dendrites
At what point do the sodium gates begin to close, shutting out further entry of sodium into the cell?
at the peak of the action potential
. Ionotropic effects are characterized by ___
rapid and short lived effects
. Ribosomes are the part of a cell that ____
synthesizes new proteins
Increased permeability to ____ would most likely result in an IPSP.
potassium
Sherrington studied ____, which are automatic muscular responses to stimuli
reflexes
Insulin increases the entry of tryptophan into the brain by ____.
causing certain competing amino acids to enter other cells, outside the brain
Temporal summation is to ____ as spatial summation is to ____
time; location
When an action potential reaches the end of an axon, the depolarization causes what ionic movement in the presynaptic
cell?
calcium into the cell
A metabotropic synapse, by way of its second messenger, ___
can influence activity in much or all of the postsynaptic cell
What ordinarily prevents extensor muscles from contracting at the same time as flexor muscles?
inhibitory synapses in the spinal cord
When a vertebrate animal contracts the flexor muscles of a leg, it relaxes the extensor muscles of the same leg.
Sherrington considered this evidence for the existence of ____.
inhibitory messages
Which terms refers to a chemical that binds to another chemical?
ligand