Question 1
Question
The rate of Ca+ diffusion across a membrane is dependent on -
Question 2
Question
Na+ concentration on either side of a membrane plays a role in osmolarity, even if it is not permeable to the membrane.
Question 3
Question
The rate of diffusion for a solute across a membrane is dependent on -
Answer
-
Concentration gradient
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Temperature
-
Viscosity of the fluid
-
All of these.
Question 4
Question
Homeostasis in physiological systems refers to the maintenance of a static or constant conditions in the internal environment.
Question 5
Question
Influences on receptor-mediated channels refers to a protein
Answer
-
Allowing other solutes to cross a membrane, after linking to a primary molecule.
-
Allowing other solutes to cross a membrane, after a voltage change to the inside of the cell.
-
Allowing other solutes to cross a membrane, after pressure changes to the inside of the cell.
-
All of these.
Question 6
Question
Osmotic pressure is the pressure necessary to allow the movement of water across a membrane.
Question 7
Question
Secondary active co-transporter proteins in a cell membrane have which of the properties listed below?
Question 8
Question
Which statement below is NOT true?
Answer
-
Voltage is "pressure" that moves electrons or ions through a circuit.
-
Current is the number of electron or ions moving per unit of time.
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Resistance is not associated with the lipid membrane.
-
Conductance is the reciprocal of resistance.
Question 9
Question
Active transport differs from facilitated diffusion in that it uses energy to move a substance uphill against its concentration gradient.
Question 10
Question
The equilibrium potential for a particular ion is the voltage in which that ions movement across a lipid membrane comes to a relative stop.
Question 11
Question
Depolarizing the membrane of excitable cells by ~10mV will initiate -
Answer
-
increases in Na+ conductance (ability to move across the membrane)
-
decreases Na+ in conductance (ability to move across the membrane)
-
closing of Na+ ions protein channels
-
cell death
Question 12
Question
The Nernst Equation is important for:
Answer
-
Determining the absolute membrane potential
-
Determining the electrical potential difference, for a single ion, needed to counter the concentration difference.
-
Determining the concentration difference, for multiple ion, needed to counter the concentration difference.
-
None of these
Question 13
Question
When determining the "equilibrium potential" for Na+, we have to assume the membrane is permeable to Na+.
Question 14
Question
Which channel is most responsible for the depolarization phase of an action potential across a cell membrane?
Answer
-
Open Na+ channels
-
Open K+ channels
-
Open Ca++ chanels
-
All of these
Question 15
Question
Which process listed below is most responsible for maintaining the electrochemical gradient?
Question 16
Question
What two factors make using the Goldman Equation more appropriate for determining the "Resting Membrane Potential", instead of using the Nertz Equation?
Answer
-
The number of voltage-gated channels located in the membrane and concentration of ions inside the cell.
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The relative ion concentration on either side of the membrane and the relative permeability of the membrane to the ions.
-
The amount of Krispy Cream donuts and Starbuck's coffee outside the cell.
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The inclusion of the relative permeability of the ions.
Question 17
Question
Which ion is most responsible for the initial change (depolarization) in membrane potential during the action potential?
Question 18
Question
Ligand-gated channels are important for initiating an action potential at the neuromuscular junction.
Question 19
Question
Slow, oxidative muscle fibers -
Question 20
Question
The sarcoplasmic reticulum stores __________ when a muscle is relaxed and releases it for binding to _______ during contraction.
Answer
-
calcium; troponin
-
calcium; tropomyosin
-
sodium; tropomyosin
-
potassium; tropinin
Question 21
Question
Put in to the correct sequence the following events involved in muscle cell contraction.
1. Voltage-gated sodium channels open, allowing sodium to flow in.
2. Spreading action potential reaches T-Tubles activating a DHP molecule.
3. Acetylcholine binds to receptors on muscle cell membrane.
4. Ligand-gated receptors allow small amounts of sodium into the cell changing membrane potential 10mV(+).
5. If enough sodium moves into the muscle cell, an impulse (action potential) develops.
Answer
-
3,4,1,5,2
-
2,1,3,4,5
-
2,4,3,1,5
-
3,4,5,1,2
Question 22
Question
Which molecule listed below is responsible for "physically" inhibiting the binding of the myosin head to the active binding site on actin?
Answer
-
Troponin
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Tropomyosin
-
G-actin
-
all of these
Question 23
Question
In order to allow discrete events to occur, calcium is rapidly removed from the cytoplasm by __________.
Question 24
Question
When an action potential is generated within a motor unit -
Answer
-
the muscle cells of the motor unit will occasionally contract.
-
only select muscle cells within the motor unit are stimulated to contract.
-
every muscle cell of the motor unit is stimulated to contract.
-
the muscle cells from the neighboring motor unit will contract.
Question 25
Question
The releasing of Ca++ inside the skeletal muscle cell (intracellular) is initiated by which protein receptor listed below?
Answer
-
Actin
-
DHP
-
Myosin
-
Tropomyosin
Question 26
Question
The t-tubules are an extension of the cell membrane of the skeletal muscle cell.
Question 27
Question
The t-tubule of cardiac muscle
Question 28
Question
The fusing of synaptic vesicles with the terminal button membrane is initiated by Ca++ influx into the cell.
Question 29
Question
The plateau of the cardiac action potential results from opening of voltage-gated, slow _______ channels in the membrane of the cardiac cell.
Answer
-
sodium
-
potasium
-
calcium
-
chloride
Question 30
Question
Heart muscle has long refractory period due to extended K+ channel opening.
Question 31
Question
Increased activity within the parasympathetic nervous system will result in changes primarily within the
Answer
-
sinoatrial node only
-
atrioventricular node only
-
ventricles only
-
sinoatrial node and atrioventricular node
-
sinoatrial node, atrioventricular node, and ventricles
Question 32
Question
Which of the following is NOT involved in triggering the normal coordinated contraction of cardiac muscle cells?
Answer
-
release of a neurotransmitter.
-
change in membrane potential within individual cardiac muscle cells
-
initiation of an action potential
-
a pacemaker potential
-
the conduction system of the heart.
Question 33
Question
The long refractory period of cardiac muscle prevents tetanic contraction of the heart.
Question 34
Question
The sinoatrial node requires external stimulation in order to generate an action potential.
Question 35
Question
Which of the following EKG events represents the depolarization of the ventricle?
Answer
-
P wave
-
QRS complex
-
PR interval
-
T wave
Question 36
Question
The spontaneous action potential generated by the Sino-Atrial Node, Atrio-ventricular Node, and Purkinje Fibers is due to K+ leaking across the cardiac muscle cell membrane.
Question 37
Question
The depolarization of the atria (by the Sino-Atrial Node) will be communicated (sent) to the ventricles (Purkinje fibers) by the _________.
Question 38
Question
Diastolic pressure generated by the right ventricle must overcome pressure in the aorta to get blood flow out to the rest of the body.
Question 39
Question
The Frank-Starling mechanism of heart contraction state that as more blood enters the heart, the heart will respond by contracting with greater force. Which is the statements below helps explain how this works?
Answer
-
The pacemaker mechanism of the heart is stimulated by increased input of blood to the left ventricle.
-
Parasympathetic inhibition of contraction will allow more force to be generated.
-
Stretched cardiac muscle has better actin/myosin filament alignment.
-
All of these.
Question 40
Question
Contraction of motor units is a(n) ____________ manner allows a muscle to maintain a level of force for a duration of time without fatiguing.
Answer
-
Synchronous
-
Asymmetrical
-
Asynchronous
-
Random
Question 41
Question
Skeletal muscle fibers operate at near-optimal sarcomere length in the normal individual.
Question 42
Question
The speed at which the action potential travels through different parts of the heart conduction system is dependent on -
Answer
-
blood flow through the heart
-
functioning of the Atrio-ventricular valve.
-
resistance to the spread of the action potential
-
phases of the moon.
Question 43
Question
The influx of calcium into the axon terminal of a chemical synapse is responsible for the ____________.
Answer
-
initiation of the action potential
-
termination of an action potential
-
fusion of the vesicles to the membrane and their exocytosis
-
movement of calcium through gap junctions
Question 44
Question
Which substance below could be used to treat 'flaccid paralysis'?
Question 45
Question
Pressure in the right atria of the heart is ~0
Question 46
Question
Ventricular cardiac muscle cells demonstrate a stable resting membrane potential with no evidence of the slow depolarization of the specialized cardiac pacemaker cells.
Question 47
Question
Which specialized muscle tissues of the heart can generate the greatest number of action potentials in a minute?
Answer
-
Sino-Atrial Node
-
Atrio-Ventricular Node
-
Purkinje fibers
-
All of the these.
Question 48
Question
An ion's overall electrochemical gradient will tend to force that ion across the membrane in a direction that will cause membrane potential to move toward that ion's equilibrium potential.
Question 49
Question
The electrical potential of a membrane at rest is closest to potassium's equilibrium potential because ___________.
Answer
-
more sodium channels are open, allowing more sodium to move into the cell.
-
more potassium channels are open, allowing more potassium to move in or out of the cell.
-
more sodium channels are closed, allowing less sodium to move in or out of the cell.
-
all of the above.
Question 50
Question
As a consequence of Frank-Starling's Law of the heart, _________________________.
Answer
-
an increase in end-systolic volume will increase stroke volume.
-
a decrease in end-diastolic volume will increase stroke volume.
-
an increase in end-diastolic volume will increase stroke volume.
-
stroke volume is unaffected by end-diastolic volume.