44 terms

Physiology Test on 12/1/2012

Which of the following statements about the resting membrane potential is TRUE?
it results in part from the concentration gradient of Na+ and K+
The resting membrane potential in a typical nerve cell is approximately?
Compared to the outside surface, the inside of a resting cell membrane is?
negatively charged
As the charge on the membrane of a typical neuron approaches 0 grom -70mV, the cell is
The ion that plays a key role in initiating electrical signals in neuron is?
Which of the following is NOT involved in creating the resting potential of neuron?
Resting membrane permeability of sodium ions greater than potassium ion.
The nerst equation predicts
the membrane potential resulting from permeability to a single ion.
The total number of neurotransmitter released at the axon terminal is directly is to a single ion.
the total number of action potential
All of the following must occur before a second action potential can begin, except:
the Na+ and K+ ions that moved in/out of the cell most move back to their original compartments.
Which of the following does NOT influence the time necessary for a nerve impulse to be conveyed by a particular neuron?
whether axon is sensory or motor.
A chemical synapse ALWAYS includes ______.

1) Axon terminal
2) Presynaptic cell
3) Synaptic Cell
4) Postsynaptic Cell
5) Dendrite Cell
1, 2, 3, 4
Inhibitory neurotransmitters of the CNS act by opening ______ channels.
Cl- & K+
Which of the following neurophysiology concepts are not match up correctly?
Falling phase of the action potential - Na+ enters the cell.
Which of the following is NOt a known drug effect on synaptic function?
Change the type of neurotransmitter found in the synaptic vesicle.
The patterns of synaptic connectivity where a large number of presynaptic neurons
When two or more graded potentials activate at the trigger zone, which of the following could happen
a. an excatory and inhibitory signal can cancel each other out.
b. two exctatory stimuli may be additive.
e. A B and C
e. A B and C
Which of the following statements in this group are true statements about IPSP and EPSP?
3, 6, 10
Temporal summation regers to ____.
additional graded potential(S) arriving before ones have ceased.
When multiple, possibly even conflicting signals reach a neuron, the neuron elevates the signals and may respond or not. The property is called?
postsynaptic intergration
The following are the main steps in the generation of an action potential. Choose the proper sequence of events.
a. the extracellular concentration of potassium will increase.
b. the intracellular concentration of sodium ion will increase.
c. the membrane resting potential will become more positive than normal.
d. all of the above-
d. all of the above
The following are the main steps in the generation of an action potential. Choose the proper sequence of events.
1. voltage gated sodium channels are inactivated
2. voltage regulated potassium, channels open and potassium moves out of the cell, initiating repolatization
3. Sodium channels regain their normal properties
4. A graded depolarization brings an area is of excitable ofan excitable membrane to
7. sodium....
4, 6, 7, 1, 2, 5, 3
The Following are steps involved in transmission at the cholinergic synapse. Choose the correct sequence of events.
3, 2, 4, 5, 1
Identify the false statement
skeletal muscle contraction is always under conscious control.
The purpose of transverse tubules is to
rapidly conduct action potential to the interior...
When a muscle cell contracts ______.
some myosin heads form cross bridges as others release actin
As ATP binds to myosin head at the beginning of a muscle contraction cycle
the myosin head detaches from actin
The power stroke begins when ____.
the inorganic phosphate and ADP are released from the myosin
As the conclusion of the power stroke
all of the above
The contraction cycle is triggered by the rise in ______ released from the sacroplasmic reticulum
Put these events in the correct chronological sequence:
1. end plate potential trigger action potentials
2. transverse tubules convey potentials into the interior of the cell
3. acetycholine binds to receptors on the motor end plate.
4. binding sites on asctin are uncovered, allowing myosin to bind and carry out power strokes.
5. Ca++ is released from the sacroplasmic reticulumn.
3, 6, 1, 2, 5, 7, 4
A 10 year old girl with type 1 diabetes develops a neuropathy limited to sensory neuron with free nerve endings. Quantitative sensory testing will reveal higher than normal thrsholds for that detection of which of the following?
The resting membrane potential?
maintains when k+ leaks out into the extracellular and is pulled back in by a more inner negative charge.
Which are of the brain exerts(s) control over the autonomic nervous system?
2) cerebellum
3) hypothalamus
4) pons
5) medulla
6) thalmus
1, 3, 4, 5
Each of these statements is true except for one. Identify exception.
activation of a receptor open Na+ channels to the membrane
Increased parasympathetic stimulation
increases gastric mobility
all of the following autonomic nervous system are true
parasympathetic involve cranial nerve (3, 7, 6, 9, 10 only)
Which statement about cardiac muscle is false?
it uses ca2+ and calmodbulin
Striated muscles are so called because of tepeating pattern oflight and dark bands. One repeating unit of the banding ppattern is called a ______.
the I band contains ______.
thin filament
which statement is true about skeletal muscle?
a. as the sacromere shortens, the two disks at each end move closer together and the I band and H band normally disappear
c. A and B
c. A and B
As the beginning of the muscle contraction cycle, the myosin head _____.
the myosin head detach from the actin.
Regulation of cross-bridge formation is accomplished by:
a. tropomyosin
c. calciu ion
a nd B
e. A B and C
A B and C
Metabolism of ____ is fastest way for cells to increase their supply of ATP in order to meet the ATP demands of heavy exercise
a. protien
b. glucose
c. fattty acids
d. A and B
e. A B and C.
A B and C
Choose the following physiological event at which the Na+ is incorrectly matched.
inactivation gate - open during re polarization gate