Exam 2: Cardio/Respiratory Flashcards by Insha Chhabra

in which structure of the heart would you find oxygenated blood?
a. right atrium
b. coronary veins
c. vena cava
d. pulmonary artery
e. pulmonary vein
f. right ventricle

e. pulmonary vein

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these great vessels carry deoxygenated blood
a. aorta & pulmonary veins
b. vena cava & pulmonary veins
c. vena cava & pulmonary arteries
d. aorta & pulmonary arteries

c. vena cava & pulmonary arteries

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which of the following patients would have the highest blood flow in the carotid artery?
a. diameter: 1.7mm, length: 7mm, viscosity: normal
b. diameter: 2mm, length: 7 mm, viscosity: normal
c. diameter: 1.9mm, length: 7mm, viscosity: normal
d. diameter: 1.6mm, length: 7mm, viscosity: high
e. diameter: 1.8mm, length: 7mm, viscosity: high

b. diameter: 2mm, length: 7 mm, viscosity: normal

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sympathetic drive would promote vasodilation of which vessels?
a. coronary arteries
b. arteries supplying the stomach
c. arteries supplying the kidney
d. arteries supplying the small intestine

a. coronary arteries

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blood that is highly viscous…
a. might result from a higher hematocrit
b. would result in more resistance
c. would slow down flow
d. two of these are correct
e. all are correct

e. all are correct

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after passing through the aortic semilunar valve, a red blood cell accidentally flows backwards through a small leak in the valve. this red blood cell landed in..

the left ventricle

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is a vessel has a higher resistance it has a __ flow

slower

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T/F: the blood that is in the ventricles diffuses to the cardiomyocytes and supplies them with blood

false

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which of the following is not a component of blood plasma?
a. proteins like albumin
b. sodium ions
c. water
d. RBC

d. RBC

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a heart murmur can be a result of a
a. turbulent flow through a stenotic valve
b. an unusually strong heart contraction
c. more filling into the ventricles
d. laminar flow through a valve

a. turbulent flow through a stenotic valve

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which of these three types of action potentials contain a calcium current?
a. nodal AP
b. cardiac AP
c. neural AP

nodal and cardiac AP

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there are two types of calcium currents…
a. in the atrial AP
b. in the ventricular AP
c. in the nodal AP
d. in the neuronal AP

c. in the nodal AP

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the T to P interval of the EKG
a. is when the atria is repolarizing
b. follows atrial depolarization
c. directly follows ventricular depolarization
d. is when the electrical activity of the heart is at or near the isoelectric line

d. is when the electrical activity of the heart is at or near the isoelectric line

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A relative of yours found out they have long QT syndrome, and it is likely a congenital genetic defect. channels during which phase of which action potential are implicated in long QT syndrome?

phase 3 (repolarization) of cardiac AP

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parasympathetic innervation of the heart is mediated through the neruotransmitter..

ACh

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the height of the P wave
a. tells you how fast the SA node is firing
b. is dependent on the placement of the recording electrodes in the EKG
c. tells you how hard the SA node is firing
d. will allow you to predict the height of the R wave

b. is dependent on the placement of the recording electrodes in the EKG

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what can you say about the refractory period in the ventricular myocytyes?
a. it is a result of Na+ influx
b. it allows the heart to fully relax
c. it is much longer than it is in skeletal muscle/nerves
d. two of these choices are correct

d. two of these choices are correct (b, c)

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the Kto or Ito channel
a. promotes the final repolarization of a ventricular and nodal myocyte
b. is present in ventricular myocytes
c. permits potassium influx
d. more than one of these is correct

b. is present in ventricular myocytes

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the AV node delay is happening during which part of the EKG?

P-Q interval

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this component of the cardiac conduction system produces a delay that allows the atria to repolarize/relax before the ventricle fully depolarizes/contracts

AV node

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in the presence of higher than usual norepinephrine and epinephrine..
a. cardiac contractility would decrease
b. ACh effects on the SA node would be enhanced
c. potassium conductance in the nodal cells would be enhanced
d. phosphate activation would be high
e. ventricular myocyte cAMP content would be high

e. ventricular myocyte cAMP content would be high

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if a friend came up to you and told you that their EKG showed they had an unusually high ejection fraction, you would say..

the EKG doesn’t give you any information about volume

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phosphorylation of the L-type channel during sympathetic drive..
a. increases potassium permeability in nodal cells
b. results in a higher peak force of contraction of the cardiomyocytye
c. speeds up the rate of relaxation of the cardiomyocyte
d. closes the channel

b. results in a higher peak force of contraction of the cardiomyocytye

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in which phase of the cardiac cycle is the volume in the ventricles actively moving from ESV toward EDV?

ventricular filling

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how does pressure in the ventricles compare to atrial and aortic pressure during the isovolumetric phases of the cardiac cycle?

it is in between atrial and aortic pressure - greater than atrial and less that aortic

which of the following channels did we say in class show an increased permeability during sympathetic drive in the nodal action potential?

funny sodium channel

in which of the following scenarios are the atrioventricular (AV) valves open? a. when atrial pressure is greater than ventricular pressure b. when the ventricles contract c. when ventricular pressure is greater than aortic pressure d. when ventricular pressure is greater than atrial pressure d. when the semilunar valves are open

a. when atrial pressure is greater than ventricular pressure

during the cardiac cycle a. the systolic duration would not be affected by heart rate b. the aortic valve closes immediately following the RS wave of the ECG c. systole precedes the QR wave of the EKG d. atrial contraction causes ventricular filling at low but not high heart rates e. ventricular blood volume remains unchanged during the initial phase of ventricular contraction

e. ventricular blood volume remains unchanged during the initial phase of ventricular contraction

according to the frank starling principle..

an increase in end diastolic volume results in an increase in stroke volume

T/F: in the presence of sympathetic drive, ejection fraction would increase

true

Of the three action potentials we've learned (neuronal, ventricular, nodal), the spike height of which ones would depend on the concentration of extracellular sodium?

neuronal, ventricular

A vessel with a radius of 1 has a flow rate of 1mm/sec. A second vessel has a radius twice that size. Assuming that each vessel has a pressure differential of 1, what would the flow be in the second vessel?

Between which points in an EKG is the SA node firing?

T wave and P wave (before the P wave)

an EKG with a higher QRS complex than normal in the same person.. a. must mean that the EDV is higher b. must mean that the person is exercising and innervating more cardiomyocytes c. must mean that atrial repol is smaller than usual so we see more ventricular repol d. must mean that the ventricular contraction is stronger than normal e. none of these are true

e. none of these

after passing through the pulmonary semilunar valve, a red blood cell accidentally flows backwards through a small leak in the valve. this RBD landed in..

the right ventricle

according to Pouiselle's law a. resistance to blood flow is proportional to the fourth power of the radius of the vessel b. rate of blood flow is inversely proportional to the fourth power of the vessel radius c. a reduction in the vessel radius by half decreases the blood flow rate to 1/16 of the original value d. doubling the radius, doubles the flow e. none of the above are true

c. a reduction in the vessel radius by half decreases the blood flow rate to 1/16 of the original value

Which of the following is/are true regarding all of the action potentials that we have learned about in class thus far? a. they all have a repolarizing potassium current b. they all have the fast inward sodium current that is responsible for initial depolarization c. they all last over 100 ms d. they all carry a calcium current e. more than one these are true f. all answers are true

a. they all have a repolarizing potassium current

Of the three action potentials we've learned (neuronal, ventricular, nodal), the duration of which of these would depend on the concentration of extracellular potassium?

all

Which of the following is/are associated with a prolonged ventricular action potential? a. long QT syndrome b. increased expression of Ito channels c. decreased expression of Ltype calcium channels d. increased expression of Kr and Ks channels e. all of the above

a. long QT syndrome

increasing heart rate would result in what changes in the cardiac cycle? a. a lower atrial pressure than at resting heart rate b. a prolonged ST segment c. higher ESV d. shorter T to P interval in the EKG e. more time for filling the heart

d. shorter T to P interval in the EKG

T/F: without the lymphatic system, we would suffer from severe edema within one day

true

a person who is regularly exercise training a. has a higher maximum heart rate b. has a higher maximal oxygen consumption c. has a lower maximal oxygen consumption d. has a higher resting heart rate e. more than one of these are correct

b. has a higher maximal oxygen consumption

a systolic pressure of 120 and a diastolic pressure of 80 would result in a pulse pressure of

___ have higher compliance and ___ have higher elasticity

veins, arteries

where in the circulatory system is the velocity of flow the lowest? a. arteries b. capillaries c. veins

b. capillaries

which of the following decreases with exercise? a. blood flow to the skeletal muscles b. heart rate c. stroke volume d. total peripheral resistance

d. TPR

of the factors affecting stroke volume, which would be heavily influenced by age? a. sympathetic nervous system effects b. preload c. afterload

c. afterload

T/F: an increased baroreceptor firing rate would increase the parasympathetic output to the SA node

true

arteriosclerosis leads to a ___ in diastolic pressure

decrease

during inspiration... a. the internal intercostal muscles contract b. the abdominal muscles contract c. intrapleural pressure becomes more negative d. alveolar pressure is greater than atmospheric pressure e. alveolar pressure is equal to atmospheric pressure

c. intrapleural pressure becomes more negative

the primary muscle of inspiration is

diaphragm

T/F: primary hypertension is far more common than secondary hypertension

true

how is the frank starling relationship altered in systolic dysfunction?

at a given EDV, there is lower stroke volume

which of the following is true regarding surfactant? a. it is important in preventing collapsing of alveoli b. makes it harder to breathe c. stiffens the lungs d. it is produced by the type I alveolar cells e. increases surface tension

a. it is important in preventing collapsing of alveoli

transpulmonary pressure is the different between

alveolar and intrapleural pressure

T/F: during resting, passive exhalation, the internal intercostals would be recruiting and contracting

false

perry's cardiologist told them that the blood flow through their left anterior descending coronary artery was limited and prescribed them a calcium channel blocker. what is the intent of this prescription? a. promote contraction of the smooth muscle cells in the coronary arteries and improve flow b. decrease resistance by increasing the radius via vasodilation of the coronary arteries to promote more flow c. promote more blood flow to the coronary arteries by strengthening the contraction of the ventricles d. increase resistance by increasing radius via vasodilation of the coronary arteries to promote more flow

b. decrease resistance by increasing the radius via vasodilation of the coronary arteries to promote more flow

myocardial infraction directly results in.. a. increased heart rate b. increased SV c. decreased CO d. high BP

c. decreased CO

hypertension can lead to ___. one way this would manifest is ___. a. systolic dysfunction, a reduced EDV b. diastolic dysfunction, a reduced EDV c. diastolic dysfunction, a reduced EF d. hypertrophic cardiomyopathy, a reduced EF e. systolic dysfunction, a reduced EF

b. diastolic dysfunction, a reduced EDV

following opening of the aortic valve a. isovolumetric contraction of the ventricle occurs b. ventricular blood volume decreases rapidly c. aortic blood pressure increases d. the QRS occurs e. the AV valve opens f. two of these are true

f. two of these are true (b, c)

phosphorylation of the L-type calcium channel during sympathetic nervous system drive.. a. ensures that the plateau phase of the cardiac action potential is prolonged b. ensures that the cardiac contraction reaches a similar peak force compared to resting conditions c. increases the rate at which the cardiomyocytes contract d. two of these are correct e. all of these are correct

c. increases the rate at which the cardiomyocytes contract

a two fold increase in stroke volume would a. have no effect on cardiac output b. usually be accompanied by a reduced heart rate c. decrease blood pressure d. increase cardiac output e. always result in a higher EDV

d. increase cardiac output

which of the following is not true about the lymphatic system? a. the lymphatic vessels are an entire other set of vessels in the body b. it helps prevent edema c. the lymphatic vessels are more porous than regular capillaries d. the lymphatic vessels are widely present throughout the brain e. lymphatic contents are eventually dumped into venous circulation

d. the lymphatic vessels are widely present throughout the brain

the P-wave in the electrocardiogram a. happens when the AV valves are closed b. can give information about how much blood is pumped out c. gives information about the oxygenation content of the blood d. represents atrial depolarization e. two of these are correct

d. represents atrial depolarization

what limits VO2 max? a. cardiac output b. oxygen delivery via respiration c. the muscles ability to use oxygen d. the fact that heart rate can only go so high e. all of these are correct

e. all of these are correct

beta-adrenergic receptors on the ventricular cardiomyocytes.. a. are stimulated by ACh and decrease heart rate b. are stimulated by ACh and increase heart rate c. are stimulated by cortisol and increase HR d. are stimulated by adrenal medulla hormones and decrease HR e. are stimulated by adrenal medulla hormones and increase HR

e. are stimulated by adrenal medulla hormones and increase HR

T/F: A person can train themselves to have a higher vital capacity

false

which of these is demonstrated by the oxygen hemoglobin dissociation curve? a. the greater the PO2 of the blood, the greater the dissociation from hemoglobin b. more additional oxygen binds to hemoglobin when going from a PO2 of 60 to 100 mmHg than is added when going from a PO2 of 40 to 60 mmHg c. as PO2 increases, the saturation of hemoglobin with oxygen increases linearly d. at normal resting systemic venous PO2, only about 75% of the hemoglobin is in the form of deoxyhemoglobin e. at normal resting systemic arterial PO2, hemoglobin is almost 100% saturated with oxygen

e. at normal resting systemic arterial PO2, hemoglobin is almost 100% saturated with oxygen

increasing tidal volume would

decrease inspiratory reserve volume

lung compliance a. is inversely related to transpulmonary pressure b. goes down in patients with fibrosis c. is often too high in patients with emphysema d. all of the above

d. all of the above

in anemia, an individual has a. fewer hemoglobins/red blood cells than normal b. carbon monoxide competitively binding with hemoglobin c. increased hematocrit d. poor oxygen saturation of hemoglobin e. two of these are correct

a. fewer hemoglobins/red blood cells than normal

as a result of an individual who is hyperventilating a. blood pH will go down b. both CO2 levels will go up and blood pH will go down c. blood CO2 levels will go up d. blood O2 levels will go down e. blood CO2 levels will go down

e. blood CO2 levels will go down

if you were to take a snapshot of the hemoglobin protein in arterial blood, you would find a. nearly all (if not all) hemoglobins are fully saturated with oxygen b. hemoglobins may have 1, 2, 3, or 4 oxygens bound in equal proportions c. hemoglobin would be about 75% saturated with oxygen and 25% of the hemoglobins would have between 0 and 3 oxygens bound d. about half of the hemoglobins are saturated with oxygen and the other half are empty

a. nearly all (if not all) hemoglobins are fully saturated with oxygen

oxygen.. a. travels from the tissue to the blood and is in higher conc in venous blood b. travels from the blood to the tissue and is in higher conc in arterial blood c. travels from the tissue to the blood and is in higher conc in arterial blood d. travels from the blood to the tissue and is in higher conc in venous blood

b. travels from the blood to the tissue and is in higher conc in arterial blood

which of the following components of lung function is not a complication of emphysema? a. decreased surface area for gas exchange b. hypoventilation c. decreased elasticity d. decreased compliance e. increased work of breathing

d. decreased compliance

which of the following are peripheral chemoreceptors sensitive to but central chemoreceptors are not sensitive to? a. PO2 b. H+ c. PCO2

a. PO2

The DRG would innervate

the external intercostals

T/F: during maximal exercise, CO2 decreases because metabolism can't keep up with ventilation

true

altitude training stimulates an increase in a. myoglobin b. hemoglobin c. erythrocyte (RBC) synthesis d. capillary number and density in muscle e. all of these options are correct

e. all of these options are correct

at a PO2 of 50 mmHG.. a. oxygen concentration is low enough to stimulate the peripheral chemoreceptors b. oxygen concentration is low enough to stimulate the central chemoreceptors c. oxygen is low, but not low enough to stimulate increased ventilation d. oxygen is high, so there's no need to increase ventilation

a. oxygen concentration is low enough to stimulate the peripheral chemoreceptors

one possible hypothesis for the cause of SIDS is a. increased mucous buildup in the lungs b. decreased surfactant production c. decreased sensitivity of chemoreceptors

c. decreased sensitivity of chemoreceptors

The pre-Botzinger complex is located in the __ and is analagous to ___ in the heart

VRG, SA node

The DRG and VRG are found in the __ of the brain

medulla

when an oxygen is bound to hemoglobin.. a. it is only in arterial blood b. it binds at a different spot than carbon monoxide would c. then a CO2 can't be bound in hemoglobin d. three other oxygens are also likely bound to that same hemoglobin

d. three other oxygens are also likely bound to that same hemoglobin

Suppose tissue cells are undergoing an unusually high amount of metabolic activity and as a result producing more H+ than usual. What can you conclude about the CO2 levels in venous blood? a. CO2 would be at 46 mmHg b. CO2 would be at 40 mmHg c. CO2 would be higher than 46 mmHg d. CO2 would be below 40mmHg

c. CO2 would be higher than 46 mmHg

Bobby finds out that his left lung is fibrotic due to his smoking habit over the past 25 years!Which of the following are true comparing Bobby's lungs now to when he was 22 (prior to the start of smoking) a. his lung compliance was higher when he was 22 b. his vital capacity was higher when he was 22 c. his vital capacity was lower when he was 22 d. both VC and lung compliance were lower at 22 e. VC was higher but lung compliance was lower at 22 f. both VC and lung compliance were higher when we was 22 g. lung compliance was lower at 22

f. both VC and lung compliance were higher when we was 22

which of the following would change VC? a. increased inspiratory reserve as a result of exercise training b. fibrotic lungs resulting in fewer functional alveoli c. higher tidal volume during a bout of exercise d. more than one of these choices are correct

b. fibrotic lungs resulting in fewer functional alveoli

surfactant can be found in the __ and promotes __ a. intrapleural space, a greater suction pressure during exhalation b. rbcs, reduced affinity of oxygen for hemoglobin c. intrapleural space, a reduced suction pressure during exhalation d. alveoli, a reduce work of breathing e. rbcs, a greater affinity of oxygen for hemoglobin f. alveoli, a reduction in compliance

d. alveoli, a reduce work of breathing

Your friend found out that he got into medical school and has a little bit of a happy-attack, complete with hyperventilation. What is going on in his body while he is hyperventilating? a. blood co2 is decreasing b. residual volume is going down c. inspiratory reserve volume is going up d. H+ excretion begins to happen as a compensation e. tidal volume is going down

a. blood co2 is decreasing

T/F: In anemia, the hemoglobin is maximally saturated with oxygen in arterial blood, but there is less hemoglobin available.

true

a rightward shift of the oxyhemoglobin dissociation curve.. a. would happen when blood CO2 content rises b. is characteristic of metabolically active tissue c. would happen with increased blood H+ content d. all but one of the answers are correct e. all of the answers are correct

e. all of the answers are correct

which of the following is true regarding carbon dioxide? a. it can bind to hemoglobin b. most of it is the form of bicarbonate in the blood c. arterial levels are around 40 mmHg d. two of these are true e. three of these are true

e. three of these are true

immediately following the right ventricle, blood flows where? a. right atrium b. left ventricle c. aorta d. pulmonary veins e. none of the above

e. none of the above

which valve directs blood between the left ventricle and aorta?

aortic semilunar valve

a leaky pulmonary semilunar valve would mean that blood would pool in the...

right ventricle

T/F: the blood that is in the ventricles is also diffusing across the cells of the myocardium, supplying them with glucose, oxygen, and other nutrients

false

which set of valves do you think are most problematic? a. aortic/bicuspid b. pulmonary/tricuspid c. bicuspid/tricuspid d. aortic/pulmonary e. none of the above

a. aortic/bicuspid - left side of heart sees more pressure

T/F: there is a period of time in a given heartbeat when all 4 valves are open

false

T/F: there is a period of time in a given heartbeat when all 4 valves are closed

true

T/F: the heart is relaxing when the AV valves are open

true

T/F: the semilunar valves are open when the heart is contracting

true

which of the following changes would most increase the resistance to blood flow in a blood vessel? a. halving the diameter b. doubling the diameter c. halving the length d. doubling the length e. decreasing the hematocrit from 50% to 40%

a. halving the diameter

a cardiac patient suffered a valve prolapse in their tricuspid valve. as a result of this problem which of the following might you expect to see a. blood leaking from the LA to RV b. blood leaking from LA to LV c. blood leaking back from the pulmonary trunk to the RV d. blood regurgitating backwards to the RA/vena cava e. A and D

d. blood regurgitating backwards to the RA/vena cava

the radius of the renal artery during sympathetic drive is 2 um. during parasymp drive, what would happen to the resistance and flow through the renal artery? a. resistance would decrease and flow would decrease b. resistance would increase and flow would increase c. resistance would decrease and flow would increase d. resistance would increase and flow would decrease

c. resistance would decrease and flow would increase

the radius of the renal artery during symp drive is 2 um. length, pressure, viscosity are constant. what would the resistance of the vessel be during parasymp drive, assuming a 2 fold change in the radius? a. 1 b. 1/4 c. 1/16 d. 1/64 e. 1/256

c. 1/16

T/F: oxygenated blood is present in the pulmonary arteries

false - deox blood here

T/F: a tricuspid valve defect would result in regurgitation of blood into the RA

true

T/F: following oxygenation in the lungs, the next place for blood to travel is the LV

false - pulmonary veins

a vessel with a radius of 1 has a flow rate of 1 mm/sec. a second vessel has a radius twice that size. assuming an equal pressure differential of 1 between the two vessels, what would the flow be in the second vessel? a. 1/16 b. 1/2 c. 2 d. 4 e. 16

e. 16

how is it possible for the heart to beat independently of the brain? a. it has a pacemaker b. it has cells that are capable of spontaneously depolarizing c. it has special sources of glucose and ATP that nowhere else on the body has d. two statements are correct e. all answers are correct

d. two statements are correct (a,b)

T/F: in muscle, contraction happens before excitation

false - depol/excitation precedes contraction

the EKG... a. represents cardiac muscle mechanical activity (contraction/relaxation) b. represents cardiac muscle electrical activity (depol/repol) e. both

b. represents cardiac muscle electrical activity (depol/repol)

which of the following would result in a prolonged cardiac (ventricular) AP? a. decreased expression of Ito channels b. decreased expression of Kr and Ks channels c. decreased expression of L-type calcium channels d. a and b e. a, b, and c

d. a and b

skeletal muscle/cardiac AP, nodal AP, ventricular AP: depolarizing current

sk - VG Na+ nodal - L-type, T-type Ca2+ vent - VG Na+

skeletal muscle/cardiac AP, nodal AP, ventricular AP: repolarizing current

sk - VG K+ nodal - rectifying K+ vent - Kr, Ks

skeletal muscle/cardiac AP, nodal AP, ventricular AP: resting current

sk - leak K+ nodal - funny Na+ vent - leak K+

skeletal muscle/cardiac AP, nodal AP, ventricular AP: other currents

sk - none nodal - none vent - Ito, L-type Ca2+

skeletal muscle/cardiac AP, nodal AP, ventricular AP: duration

sk - 1-3 ms nodal - 200-300 ms vent - 250-400 ms

skeletal muscle/cardiac AP, nodal AP, ventricular AP: refractory period?

yes for all

skeletal muscle/cardiac AP, nodal AP, ventricular AP: steady RMP?

sk - yes nodal - no vent - yes

T/F: action potential duration is primarily determined by potassium current (not calcium)

true

how does SA node firing relate to the P wave? a. unrelated b. comes before it c. comes after it

b. comes before it

when during the EKG would you see the ventricle muscle contracting? a. during the QRS complex b. from the Q through the T wave c. from the S through the T wave

b. from the Q through the T wave

which part of the EKG represents contraction of the atria? a. P wave b. QRS complex c. T wave d. none of these, the EKG only shows electrical activity

d. none of these, the EKG only shows electrical activity

under what circumstances would the P-P interval be longer? a. increased HR b. decreased HR

b. decreased HR

P-P interval is 0.5 seconds. what is heart rate?

120

in the EKG.. a. the P to Q interval would be happening when the ventricular action potentials are at their plateau phase b. the T to P interval is prolonged during a bout of exercise c. atrial repolarization happens during the QRS complex d. SA node firing is indicated by the P wave e. AV node firing is indicated by the Q wave

c. atrial repolarization happens during the QRS complex

atropine is a drug used to treat symptoms of bradycardia (low heart rate). it affects the parasympathetic nervous system input to the heart. knowing this, which of the following is atropine? a. a muscarinic receptor antagonist b. a muscarinic receptor agonist c. a beta adrenergic antagonist d. a beta adrenergic agonist

a. a muscarinic receptor antagonist