PSYC 3510 LATEST UPDATE EXAM 1

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PSYC 3510 LATEST UPDATE EXAM 1/

ACTUAL EXAM QUESTIONS WITH CORRECT

DETAILED ANSWERS (VERIFIED ANSWERS)

GRADED A+

What is neuroscience? - Correct Answer - the study of the nervous system and behavior

What is behavioral neuroscience? - Correct Answer - the study of relationships between behavior and the body, particularly the brain

This difference in electrical charge is referred to as a - Correct Answer - voltage

resting potential - Correct Answer - -The resting potential is the difference in charge between the inside and outside of the membrane of a neuron at rest.-Between -40 and -80 mV in different neurons

A typical neuron's resting potential is around - Correct Answer - -70 mV

resting potential caused by - Correct Answer - -unequal distribution of ions on either side of the membrane -Outside contains mostly sodium (Na+) and chloride (Cl-) ions -Inside contains mostly potassium (K+) ions and organic anions (A-)

sodium potassium pump - Correct Answer - Moves 3 Na+ outside for every 2 K+ inside

-Large protein molecules that move sodium ions through the neuron membrane to the outside and potassium ions back inside, helping to maintain the resting potential. 1 / 4

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force of diffusion - Correct Answer - Ions flow from high to low concentration -The pressure exerted by ions from an area of greater concentration to an area where they are less concentrated.

electrostatic pressure - Correct Answer - Ions attracted to the opposite charge (+ to -), and repelled by the same charge (+ from +) -The force by which like-charged ions are repelled by each other and opposite-charged ions are attracted to each other.

excitatory signals - Correct Answer - causes a change in ion balance, which spreads to adjacent membrane

spreading diminishes over distance - Correct Answer - so it is often referred to as a local potential

if depolarization reaches threshold - Correct Answer - (around -60 mV), an action potential will be triggered

ligand bindings - Correct Answer - causes a change in ion balance, which spreads to adjacent membrane

the local potential is a - Correct Answer - -graded potential: changes in membrane potential that vary in size, as opposed to being all-or-none. They arise from the summation of the individual actions of ligand-gated ion channel proteins, and decrease over time and space

-varies in magnitude with stimulus strength -is decremental

decremental - Correct Answer - magnitude decreases with distance

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pg. 3 the inside of the neuron is relatively poor in ___ ions and rich in ___ ions - Correct Answer - sodium, potassium

the rate law - Correct Answer - explains how the intensity of stimuli is represented

Without the sodium-potassium pump, the neuron would become - Correct Answer - overfilled with sodium ions and unable to fire

there is a limit to how rapidly a neuron can produce action potentials. This is due to - Correct Answer - the absolute refractory period

saltatory conduction results in - Correct Answer - greater speed with the use of less energy

general anesthetics open potassium channels, allowing potassium ions to leak out of the neuron. This - Correct Answer - hyper polarizes the neuron, preventing firing

when the action potential arrives at the terminal button, entry of ___ ions stimulates release of transmitter - Correct Answer - calcium

all the following neurotransmitters are deactivated by the reuptake except - Correct Answer - acetylcholine

an inhibitory neurotransmitter causes the inside of the post synaptic neuron to become - Correct Answer - more negative

excitatory postsynaptic potentials are typically produced by movement of ___ ions, whereas inhibitory postsynaptic potentials are typically produced by movement of ___ ions - Correct Answer - sodium, potassium or chloride

which of the following is not an example of regulation of synaptic activity? - Correct Answer - a presynaptic neuron inhibits a postsynaptic neuron 3 / 4

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the presence of synapses in a neuron chain provides the opportunity for - Correct Answer - modification of neural activity

groups of cell bodies in the CNS are called - Correct Answer - nuclei

the prefontrol cortex is involved in all but which one of the following functions? - Correct Answer - orienting the body in space

the action potential follows the - Correct Answer - -all or none law

-always occurs at full strength or not at all -is nondecremental

nondecremental - Correct Answer - message travels over long distances at the same amplitude -A property of the action potential, which travels through the neuron without any decrease in size

Inactivated sodium channels create an - Correct Answer - absolute refractory period

neurons cannot generate another impulse - Correct Answer - Limits frequency of firing Action potential is only forward moving

open potassium channels create a - Correct Answer - relative refractory period

action potential generated - Correct Answer - only in response to stronger-than- threshold stimulus

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