3715118
Pregunta 1
Pregunta
The rate of Ca+ diffusion across a membrane is dependent on -
Respuesta
-
Permeability of the membrane on the solute
-
Concentration gradient
-
Existence of carriers and/or channels for the solute
-
All of these are true.
Pregunta 2
Pregunta
Na+ concentration on either side of a membrane plays a role in osmolarity, even if it is not permeable to the membrane.
Respuesta
- True
- False
Pregunta 3
Pregunta
The rate of diffusion for a solute across a membrane is dependent on -
Respuesta
-
Concentration gradient
-
Temperature
-
Viscosity of the fluid
-
All of these.
Pregunta 4
Pregunta
Homeostasis in physiological systems refers to the maintenance of a static or constant conditions in the internal environment.
Respuesta
- True
- False
Pregunta 5
Pregunta
Influences on receptor-mediated channels refers to a protein
Respuesta
-
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.
Pregunta 6
Pregunta
Osmotic pressure is the pressure necessary to allow the movement of water across a membrane.
Respuesta
- True
- False
Pregunta 7
Pregunta
Secondary active co-transporter proteins in a cell membrane have which of the properties listed below?
Respuesta
-
Selectiveity
-
Uses energy from solute concentration gradient (runs downhill)
-
Saturable
-
All of these.
Pregunta 8
Pregunta
Which statement below is NOT true?
Respuesta
-
Voltage is "pressure" that moves electrons or ions through a circuit.
-
Current is the number of electron or ions moving per unit of time.
-
Resistance is not associated with the lipid membrane.
-
Conductance is the reciprocal of resistance.
Pregunta 9
Pregunta
Active transport differs from facilitated diffusion in that it uses energy to move a substance uphill against its concentration gradient.
Respuesta
- True
- False
Pregunta 10
Pregunta
The equilibrium potential for a particular ion is the voltage in which that ions movement across a lipid membrane comes to a relative stop.
Respuesta
- True
- False
Pregunta 11
Pregunta
Depolarizing the membrane of excitable cells by ~10mV will initiate -
Respuesta
-
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
Pregunta 12
Pregunta
The Nernst Equation is important for:
Respuesta
-
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
Pregunta 13
Pregunta
When determining the "equilibrium potential" for Na+, we have to assume the membrane is permeable to Na+.
Respuesta
- True
- False
Pregunta 14
Pregunta
Which channel is most responsible for the depolarization phase of an action potential across a cell membrane?
Respuesta
-
Open Na+ channels
-
Open K+ channels
-
Open Ca++ chanels
-
All of these
Pregunta 15
Pregunta
Which process listed below is most responsible for maintaining the electrochemical gradient?
Respuesta
-
Facilitated diffusion of Na+
-
Na+/K+ pump
-
Ca++ storage
-
Starbuck's Coffee and Krispy Cream.
Pregunta 16
Pregunta
What two factors make using the Goldman Equation more appropriate for determining the "Resting Membrane Potential", instead of using the Nertz Equation?
Respuesta
-
The number of voltage-gated channels located in the membrane and concentration of ions inside the cell.
-
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.
-
The inclusion of the relative permeability of the ions.
Pregunta 17
Pregunta
Which ion is most responsible for the initial change (depolarization) in membrane potential during the action potential?
Respuesta
-
Na+
-
K+
-
Ca++
-
Cl-
Pregunta 18
Pregunta
Ligand-gated channels are important for initiating an action potential at the neuromuscular junction.
Respuesta
- True
- False
Pregunta 19
Pregunta
Slow, oxidative muscle fibers -
Respuesta
-
Use mainting oxidative phosphorylation to generate ATP.
-
Have large amounts of mitochondria.
-
Have large blood supply.
-
All of these.
Pregunta 20
Pregunta
The sarcoplasmic reticulum stores __________ when a muscle is relaxed and releases it for binding to _______ during contraction.
Respuesta
-
calcium; troponin
-
calcium; tropomyosin
-
sodium; tropomyosin
-
potassium; tropinin
Pregunta 21
Pregunta
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.
Respuesta
-
3,4,1,5,2
-
2,1,3,4,5
-
2,4,3,1,5
-
3,4,5,1,2
Pregunta 22
Pregunta
Which molecule listed below is responsible for "physically" inhibiting the binding of the myosin head to the active binding site on actin?
Respuesta
-
Troponin
-
Tropomyosin
-
G-actin
-
all of these
Pregunta 23
Pregunta
In order to allow discrete events to occur, calcium is rapidly removed from the cytoplasm by __________.
Respuesta
-
dihydropyridime channels
-
calcium-sequestering proteins in the cytoplasm
-
calcium pumps in the sarcoplasmic reticulum
-
DHP receptor
Pregunta 24
Pregunta
When an action potential is generated within a motor unit -
Respuesta
-
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.
Pregunta 25
Pregunta
The releasing of Ca++ inside the skeletal muscle cell (intracellular) is initiated by which protein receptor listed below?
Respuesta
-
Actin
-
DHP
-
Myosin
-
Tropomyosin
Pregunta 26
Pregunta
The t-tubules are an extension of the cell membrane of the skeletal muscle cell.
Respuesta
- True
- False
Pregunta 27
Pregunta
The t-tubule of cardiac muscle
Respuesta
-
form the Z lines
-
stores K+
-
provides a means of rapidly transmitting action potential to the sarcoplasmic reticulum via the DHP molecule
-
are larger than those found in skeletal muscle.
Pregunta 28
Pregunta
The fusing of synaptic vesicles with the terminal button membrane is initiated by Ca++ influx into the cell.
Respuesta
- True
- False
Pregunta 29
Pregunta
The plateau of the cardiac action potential results from opening of voltage-gated, slow _______ channels in the membrane of the cardiac cell.
Respuesta
-
sodium
-
potasium
-
calcium
-
chloride
Pregunta 30
Pregunta
Heart muscle has long refractory period due to extended K+ channel opening.
Respuesta
- True
- False
Pregunta 31
Pregunta
Increased activity within the parasympathetic nervous system will result in changes primarily within the
Respuesta
-
sinoatrial node only
-
atrioventricular node only
-
ventricles only
-
sinoatrial node and atrioventricular node
-
sinoatrial node, atrioventricular node, and ventricles
Pregunta 32
Pregunta
Which of the following is NOT involved in triggering the normal coordinated contraction of cardiac muscle cells?
Respuesta
-
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.
Pregunta 33
Pregunta
The long refractory period of cardiac muscle prevents tetanic contraction of the heart.
Respuesta
- True
- False
Pregunta 34
Pregunta
The sinoatrial node requires external stimulation in order to generate an action potential.
Respuesta
- True
- False
Pregunta 35
Pregunta
Which of the following EKG events represents the depolarization of the ventricle?
Respuesta
-
P wave
-
QRS complex
-
PR interval
-
T wave
Pregunta 36
Pregunta
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.
Respuesta
- True
- False
Pregunta 37
Pregunta
The depolarization of the atria (by the Sino-Atrial Node) will be communicated (sent) to the ventricles (Purkinje fibers) by the _________.
Respuesta
-
Sarcoplasmic reticulum
-
DHP molecule
-
A-V bundle (bundle of His)
-
Actin and myosin filaments.
Pregunta 38
Pregunta
Diastolic pressure generated by the right ventricle must overcome pressure in the aorta to get blood flow out to the rest of the body.
Respuesta
- True
- False
Pregunta 39
Pregunta
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?
Respuesta
-
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.
Pregunta 40
Pregunta
Contraction of motor units is a(n) ____________ manner allows a muscle to maintain a level of force for a duration of time without fatiguing.
Respuesta
-
Synchronous
-
Asymmetrical
-
Asynchronous
-
Random
Pregunta 41
Pregunta
Skeletal muscle fibers operate at near-optimal sarcomere length in the normal individual.
Respuesta
- True
- False
Pregunta 42
Pregunta
The speed at which the action potential travels through different parts of the heart conduction system is dependent on -
Respuesta
-
blood flow through the heart
-
functioning of the Atrio-ventricular valve.
-
resistance to the spread of the action potential
-
phases of the moon.
Pregunta 43
Pregunta
The influx of calcium into the axon terminal of a chemical synapse is responsible for the ____________.
Respuesta
-
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
Pregunta 44
Pregunta
Which substance below could be used to treat 'flaccid paralysis'?
Respuesta
-
Curare
-
Botulinum Toxin
-
Tetanus Toxin
-
Diisoprophyl fluorophosphate
Pregunta 45
Pregunta
Pressure in the right atria of the heart is ~0
Respuesta
- True
- False
Pregunta 46
Pregunta
Ventricular cardiac muscle cells demonstrate a stable resting membrane potential with no evidence of the slow depolarization of the specialized cardiac pacemaker cells.
Respuesta
- True
- False
Pregunta 47
Pregunta
Which specialized muscle tissues of the heart can generate the greatest number of action potentials in a minute?
Respuesta
-
Sino-Atrial Node
-
Atrio-Ventricular Node
-
Purkinje fibers
-
All of the these.
Pregunta 48
Pregunta
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.
Respuesta
- True
- False
Pregunta 49
Pregunta
The electrical potential of a membrane at rest is closest to potassium's equilibrium potential because ___________.
Respuesta
-
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.
Pregunta 50
Pregunta
As a consequence of Frank-Starling's Law of the heart, _________________________.
Respuesta
-
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.
¿Quieres crear tus propios Tests gratis con GoConqr? Más información.