Chapter 12 Nervous system study questions

This potential is______ mV. This is a change of ________ from the RMP.

-55/+15mV

Place the items in the correct order for an IPSP from beginning to end.

1.) an inhibitory neurotransmitter binds to chemically gated K+ channels 2.) K+ channels open 3.) K+ flows out of the neuron 4.) the inside of the neuron becomes more negative 5.) the IPSP propagates toward the axon hillock

Place the items for an EPSP in the correct order from beginning to end.

1.) excitatory neurotransmitter released from presynaptic neuron 2.) neurotransmitter binds to chemically gated sodium channels 3.) sodium channels open 4.) sodium flows into neuron 5.) inside of neuron becomes more positive 6.) this EPSP propagates toward axon hillock

local potential

IPSP, reversible and decremental

The time when there is complete insensitivity of the plasma membrane to another stimulus

absolute refactory period

The initial segment, by adding postsynaptic potentials, determines if a(n) ____________ potential is reached.

action

Neurons are classified functionally according to the direction the ____________ travels relative to the ____________ .

action potential/cns

Interneurons (or__________ neurons) lie entirely within the CNS. They receive stimulation from many other neurons and carry out the integrative function of the nervous system.The most numerous types of neurons are ___________.

association/interneurons

The motor division is separated further into a somatic motor division and a(n) ____________ motor division.

autonomic

Efferent neurons are the neurons of the motor nervous system, conducting motor output from the CNS to the _____. All motor neurons are ________.

effectors./ multipolar.

The afferent or sensory division transmits impulses ____________ .

from peripheral organs to CNS

The efferent or motor division transmits impulses ____________ .

from the CNS out to the peripheral organs

EPSP and IPSP _________ potentials are local currents of ions that move along the plasma membrane toward the initial segment area of the __________.

graded/ axon hillock

Neurotransmitters combine with their receptor sites and cause ___gated ion channels to open.

ligand

The peripheral nervous system is further subdivided into an afferent (sensory) division and an efferent ( ____________ ) division.

motor

Calcium ions diffuse into the cell and cause synaptic vesicles to release

neurotransmitters.

Graded ____________ potentials are added together in the initial segment; this process is called ____________ .

postsynaptic/ summation

Neurotransmitters diffuse from the terminal across the synaptic cleft.

presynaptic

A time when there is a decrease in the sensitivity of the plasma membrane to further stimulation.

refractory period

The time when a stronger-than-threshold stimulus is needed to initiate another action potential.

relative refactory period

action potential

requires threshold important for transmission over long distances.

Afferent neurons are the neurons of the sensory nervous system.They are responsible for conducting ____________ input from both somatic sensory and visceral sensory receptors. Most sensory neurons are ____________

sensory, unipolar

Autonomic refers to the controls we are not aware of, like ____________ muscle, cardiac muscles, and glands

smooth

Action potentials arriving at the presynaptic terminal cause_____-gated calcium channels to open.

voltage