In a polarized neuron at rest, which ion is concentrated outside the cell?
Na+
Ca++
None of the above
K+
The period of time in which the neuron cannot generate another action potential is called the
all or none period
refractory period
latent period
sublimial period
A typical resting membrane potential is
+30 mv
0 mv
-70 mv
+100 mv
Impulses are conducted from one neuron to another across a
Ganglion
synapse
neurofibral node
neuroeffector junction
Which of the following is true about synapses?
Neurotransmitters are released by the dendrites at synapses
information jumps synapses in the form of electric arcs
neurotransmitters are released in the form of Na and K vesicles
information passes in only one direction across synapses
Which of the following best describes the transmission of an impulse along a neuron?
the movement of a neurotransmitter along a neuronal membrane
sodium and potassium ions moving over the surface of the neuron
a wave of depolarization spreading from the point of the stimulus
positive charges spreading over the surface of an excitable cell
Which of the following is released by a presynaptic neuron to generate an impulse in the postsynaptic neuron?
an electric spark
integrators
neurotransmitters
packets of sodium and potassium
The thalamus and hypothalamus are parts of the brain located in the
Diencephalon
Pons
Medulla oblongata
Midbrain
the ability of neurons to respond to stimuli and convert them to impulse is called
excitability
faciliation
summation
depolarization
the type of neuroglial cell found between neurons and blood vessels that join parts by numerous cellular processes are
astrocytes
ependymal cells
oligodendrocytes
microglial cells
emotions of fear, anger, and pleasure are produced by the
pons
cerebellum
limbic system
medulla oblongata
which of the following is not a structural feature of a neuron?
neurolemma
missl granules
axon
the job of maintaining homeostasis is a function of the ___ and ___ systems
nervous...endocrine
nervous...digestive
endocrine...digestive
urinary...digestive
if a neuron within the CNS has its axon severed,
the neuron will be spurred to reproduce a fully functional one
the neuron will lose its funstion
the neuron will most likely die
it will soon regenerate
It can be said that in a resting neuron, the
inside of the cell is more electropositive than the outside
concentration of K+ ions is greater outside the cell
membrane is polarized
all of the above
A cross section of the cord reveals a core of white matter surrounded by gray matter
neurons, like muscle fibers, conduct impulses according to the all or none response
A nerve impulse would travel faster down a myelinated C fiber
Synaptic conduction of a nerve impulse can be affected by changes is pH
during a neuron's resting state, it is full of Na+ ions
neurons have plasma membranes which contain a variety of ion charges
A neuron will respond maximally to a sub-threshold stimulus
the jejenum is the first part of the small intestine
One part of the stomach is called the cardiac region
Cells that secrete hydrochloric acid are called chief cells
peristalsis acts to move food along the alimentary tube
the starting place for chemical digestion is the stomach
One function of the esophagus is to coat the bolus with mucus
The digestive enzyme pepsin secreted by gastric glands begins the digestion of
sucrose
fat
protein
carbs
The main part of the stomach is called the
fundic region
pyloric region
cardiac region
none of these
The salivary enzyme amylase functions to digest
fats
all of these
proteins
The teeth that are best adapted for biting off large pieces of food is called the
incisors
cuspids
molars
bicuspids
Peristalsis occurs in the digestive tract
from the pharynx to anus
in the stomach and small intestines only
in the small and large intestines only
in the stomach, small intestine, and large intestines only
The material that covers the crown of the teeth is
cementum
dentin
enamel
plaque
What parts of a tooth are destroyed by dental caries?
Enamel
Dentin
Pulp
Cementum
The digestive enzyme pepsin secreted by gastric glands begins in the digestion of
carbohydrates
Type A hepatitis is transmitted by
Ingestion of food contaminated by feces
transfusion with blood contaminated by the hepatitis virus
use of improperly cleaned needles
sexual activity
The foods that stay in the dtomach for longest are high in
amino acids