The portions of a neuron that extend off of the roughly spherical cell body are usually collectively called

projections

Neurotransmitter is stored and released from

axon terminals and axon varicosities.

The afferent and efferent axons together form

peripheral nervous system

Exocrine glands, smooth muscles, and cardiac muscles are controlled by the

autonomic nervous system

Autonomic motor neurons are subdivided into the

sympathetic and parasympathetic divisions

The enteric nervous system is a network of neurons that function in controlling

digestion

nervous system is composed of which two types of cells

neurons and glial

The multiple thin, branched structures on a neuron whose main functions is to receive incoming signals are

dendrites

The axon is connected to the cell body by the

axon hillock

The term axonal transport refers to

transport of proteins and organelles down the axon

these glial cells act as scavengers

microglial

Which ion is higher in concentration inside the cell compared to outside?

potassium

What ion is responsible for rising phase of action potential?

sodium

The rising phase of the action potential is due to

Na+ flow into the cell

The falling phase of the action potential is due primarily

K+ out of the cell

The point during an action potential when the inside of the cell has become more positive than the outside is called

overshoot

The absolute refractory period of an action potential

ensures one way travel down an axon allows a neuron to ignore a second signal sent that closely followed first, and prevents summation of action potential.

The all-or-none principle states that

all stimuli great enough to bring the membrane to threshold will produce action potentials of identical magnitude.

In the membrane of a resting nerve cell, when chemically gated Cl¬- channels open the cell becomes

depolarized

Action potentials are primarily associated with the membranes of

axons only

Graded potentials may

initiate an action potential, depolarize the membrane to the threshold voltage, hyperpolarize the membrane, be called EPSPs or IPSPs.

Some neurotoxins work essentially the same way as some local anesthetics, which is to

bind to Na+ channels and inactivate them and prevent depolarization by blocking Na+ entry into the cell.

A chemical synapse ALWAYS includes

presynaptic cell, synaptic cleft, and postsynaptic cell.

Which type of synapse is most prevalent in the nervous system

electrical

Which is the most common inhibitory neurotransmitter of the CNS?

GABA and glycine

The inhibitory neurotransmitters of the CNS, GABA and glycine, act by opening

only Cl- channels.

Excitatory neurotransmitters of the CNS usually act by opening

Na+ channels

Once the action potential reaches the axon terminal, what happens next?

release of the neurotransmitter into the synaptic cleft

Calcium is important in the synapse because it

signals exoctytosis

Spatial summation refers to

multiple graded potentials arriving at one location simultaneously.

A damaged neuron has a better chance of survival and repair if the _______ is not damaged

cell body

graded or action potential
May be hyperpolarizing

graded

graded or action potential
originates at the trigger zone

action

graded or action potential
originates on dendrites and cell bodies

graded

graded or action potential
can involve ion channels regulated by chemicals

graded

graded or action potential
requires a minimum stimulus to occur

action

graded or action potential
size increases if stimulus strength increases

graded

graded or action potential
result from influx of sodium

both

The two types of electrical signals in neurons are

graded and action

T/F
The minimum amount of stimulus required to depolarize an excitable membrane and generate an action potential is known as the threshold

true

the two factors that influence the membrane potential.

The concentration gradients of ions across the membrane. The membrane permeability to those ions.

internal clock of mammals appears to be located in the

pituitary gland

Substances that have been isolated form the blood and have been shown to induce sleep linked to the

immune system

Which brain area is considered to be a key integrating center for homeostasis

hypothalamus

hormone that is released to enhance the fight-or-flight reaction

epinephrine

brain area acknowledged as the center for emotions

amyglada

important structure in both learning and memory is the

hippocampus

inability to remember newly acquired information is called

anterograde amnesia.

point during action potential when the inside if the cell becomes more positive than outside:

overshoot

Action potentials are associated with membranes of:

axons only

Portions of a neuron that extend off rough cell body are called

processes

Nervous system is composed of 2 types

neurons and glial

which part of the neuoron receive incoming signal

dendrites