Cardiovascular System- Physiology PMU- 2nd Year 2nd Sem

Descrição

Cardiovascular System- Physiology PMU- 2nd Year 2nd Sem
Med Student
Quiz por Med Student , atualizado more than 1 year ago
Med Student
Criado por Med Student mais de 7 anos atrás
1126
29

Resumo de Recurso

Questão 1

Questão
The pacemaker of the heart is normally the:
Responda
  • sino-atrial node
  • atrio-ventricular node
  • bundle of Hiss
  • mitral valve
  • left ventricle

Questão 2

Questão
In electrocardiogram (ECG) the QRS complex represents:
Responda
  • depolarisation of the atria
  • repolarization of the atria
  • depolarisation of the ventricles
  • repolarization of the ventricles
  • delay at the AV node

Questão 3

Questão
An ECG would be useful for determining a patient's:
Responda
  • heart murmur
  • stroke volume
  • cardiac output
  • blockage of conduction of electrical signals between the atria and the ventricles
  • none of the above

Questão 4

Questão
Cardiac output (C.O.) is the:
Responda
  • volume of blood pumped per minute by both ventricles
  • volume of blood flowing through the systemic circulation each minute
  • product of the number of heartbeats per minute and the volume pumped per beat
  • a and c
  • b and c

Questão 5

Questão
According to the Frank-Starling mechanism of the heart
Responda
  • with each systole the left ventricle ejects a larger volume of blood then the right ventricle
  • the intrinsic rate of the heart's pacemaker is 100 beats per minute
  • cardiac output increases with increased heart rate
  • stroke volume increases with increased venous return
  • both ventricles contact simultaneously

Questão 6

Questão
Distinguishing characteristics of the veins include the following
Responda
  • all veins carry deoxygenated blood
  • all veins carry blood towards the heart
  • all veins have thick elastic walls
  • a and b
  • b and c

Questão 7

Questão
During exercise, there is an increased flow of blood to
Responda
  • the brain
  • the kidneys
  • the muscles
  • b and c
  • a, b and c

Questão 8

Questão
Which of the following does not contribute to the increased stroke volume (SV) during exercise
Responda
  • increased contractility of the cardiac muscle
  • increased venous return
  • increased length of filling time during diastole
  • increased sympathetic stimulation of the ventricular muscle
  • increased end-diastolic volume

Questão 9

Questão
The aortic valve
Responda
  • prevents the backflow of blood into the aorta during ventricular diastole
  • prevents the backflow of blood into the left ventricle during ventricular diastole
  • prevents the backflow of blood into the left ventricle during ventricular ejection
  • prevents backflow of blood into the aorta during injection
  • closes when the first heart sound is heard

Questão 10

Questão
In humans, blood loss causes
Responda
  • venous constriction
  • decreased blood flow to the skin
  • a fall in the cardiac output
  • splenic contraction
  • a, b and c

Questão 11

Questão
Angiotensin ll:
Responda
  • as an octapeptide
  • is produced mainly in the lungs
  • causes thirst
  • stimulates the secretion of the antidiuretic hormone (ADH)
  • all of the above

Questão 12

Questão
Which of the following organs has the greatest blood flow per 100 g of tissue?
Responda
  • brain
  • heart muscle
  • skin
  • liver
  • kidney

Questão 13

Questão
If the heart rate is 70 beats/min, then cardiac output is closer to:
Responda
  • 3.45 l.min-1
  • 4.55 l.min-1
  • 5.25 l.min-1
  • 8.0 l.min-1
  • 9.85 l.min-1

Questão 14

Questão
The ventricles are completely depolarized during which portion of the ECG?
Responda
  • PQ interval
  • QRS complex
  • QT interval
  • ST segment
  • T wave

Questão 15

Questão
Cardiac output (CO) of the right heart is what percentage of that of the left?
Responda
  • 25%
  • 50%
  • 75%
  • 100%
  • 125%

Questão 16

Questão
The action potential corresponds to which portion of the ECG?
Responda
  • P wave
  • PQ interval
  • QRS complex
  • ST segment
  • QT interval

Questão 17

Questão
Which effects are caused by sympathetic stimulation?
Responda
  • increased force of heart contraction
  • increased heart metabolism
  • increased heart conductibility
  • decreased excitability
  • a, b, and c

Questão 18

Questão
Which are the peculiarities of the action potential in cardiac muscle?
Responda
  • long duration (0.3 s)
  • short duration (0.01 s)
  • high amplitude
  • plateau
  • a, and d

Questão 19

Questão
Excitation from SA node to AV node is conducted by:
Responda
  • Nodal fibers
  • Internodal fibers
  • Atrial cardiac cells
  • His bundle
  • b, and c

Questão 20

Questão
When are all four valves closed?
Responda
  • during isovolumetric ventricular contraction
  • during isovolumetric ventricular relaxation
  • during ventricular systole
  • during atrial diastole
  • a, and b

Questão 21

Questão
Effects of hypokalaemia:
Responda
  • short PQ interval
  • ventricular extrasystoles
  • elevated ST segments
  • long QRS interval
  • long QT interval

Questão 22

Questão
Hyperkalaemia:
Responda
  • causes a prolonged QT interval
  • prolongs the QRS
  • causes ST segment elevation
  • potentiates digoxin toxicity
  • causes loss of P wave

Questão 23

Questão
Left ventricular end-diastolic volume is:
Responda
  • 10 - 30 ml
  • 30 - 50 ml
  • 50 - 70 ml
  • 70 - 100 ml
  • 100 - 130 ml

Questão 24

Questão
Local metabolic control is most important in determining flow to the:
Responda
  • skin
  • lungs
  • skeletal muscles
  • kidneys
  • liver

Questão 25

Questão
The atrial component of ventricular filling is:
Responda
  • 5%
  • 10%
  • 30%
  • 50%
  • 80%

Questão 26

Questão
The lowest intrinsic discharge activity resides in the:
Responda
  • SA node
  • AV node
  • Bundle branches
  • Purkinje fibers
  • Ventricular fibers

Questão 27

Questão
Slowest conduction (velocity) occurs in the:
Responda
  • Atrium
  • AV node
  • Bundle of His
  • Purkinje fibers
  • Ventricular muscle

Questão 28

Questão
Which one of the following causes vasodilatation:
Responda
  • TXA2
  • Serotonin (5-HT)
  • Endothelin
  • Neuropeptide Y
  • VIP

Questão 29

Questão
The highest oxygen extraction is found in the:
Responda
  • carotid body
  • heart
  • kidneys
  • brain
  • lungs

Questão 30

Questão
The fastest conduction velocity is found in the:
Responda
  • SA node
  • Atrial muscle
  • AV-node
  • Bundle of His
  • Ventricular conduction system (Purkinje system)

Questão 31

Questão
Oxygen consumption at rest is the highest in the:
Responda
  • brain
  • heart
  • liver
  • kidneys
  • skeletal muscles

Questão 32

Questão
Coronary blood flow is:
Responda
  • dominant in the left coronary artery in 60% of people
  • better supply to subendocardium during systole
  • better supply to subendocardium during diastole
  • better supply to left ventricle during systole
  • left > right during systole

Questão 33

Questão
The velocity of blood flow is greatest in:
Responda
  • capillaries
  • pulmonary vein during diastole
  • small arteries
  • inferior vena cava
  • the aorta

Questão 34

Questão
Arterial baroreceptor afferents:
Responda
  • reach the spinal cord via sympathetic nerves
  • utilize glycine as a neurotransmitter
  • primary synapse in C1 area of the medulla
  • activate GABA inhibitory interneurons
  • excite autonomic efferents in the anterolateral horn

Questão 35

Questão
Isovolumetric contraction is associated with:
Responda
  • immediate increase in heart rate due to cardiac sympathetics
  • cardiac output increased/unchanged
  • increased systolic blood pressure and decreased diastolic blood pressure
  • does not work
  • decrease stroke volume

Questão 36

Questão
Baroreceptors are not located in:
Responda
  • carotid sinus
  • carotid body
  • right atrium
  • aortic arch
  • large veins

Questão 37

Questão
The volume of blood is the greatest in the:
Responda
  • systemic capillaries
  • large veins
  • small arteries
  • the liver
  • the lungs

Questão 38

Questão
The standard ECG setting is:
Responda
  • speed 50 mm.s-1 50 mm/mv
  • speed so mm.s-1 25 mm/mV
  • speed 25 mm.s-1 25 mm/mV
  • speed 25 mm.s-1 50 mm/mV
  • none of the above

Questão 39

Questão
Long term control of tissue blood flow includes:
Responda
  • adenosine
  • nitric oxide
  • change in tissue vascularity
  • oxygen tension at the precapillary sphincter
  • aldosterone

Questão 40

Questão
Turbulence is more likely with:
Responda
  • small tube diameter
  • high density fluid
  • increased tube length
  • increased viscosity
  • none of the above

Questão 41

Questão
The following would directly increase heart rate
Responda
  • sympathetic stimulation
  • parasympathetic stimulation
  • decreased blood pressure
  • b, and c
  • none of the above

Questão 42

Questão
At any given time the largest amount of blood in the body is carried by:
Responda
  • veins
  • capillary beds
  • arterioles
  • aorta
  • vena cava

Questão 43

Questão
The pacemaker of the heart is:
Responda
  • AV node
  • Purkinje fibers
  • AV bundle
  • SA node
  • None of the above

Questão 44

Questão
The T wave in an ECG indicates:
Responda
  • Resting potential
  • Atrial depolarization
  • SA node excitation
  • Ventricle repolarization
  • Purkinje excitation

Questão 45

Questão
End diastolic volume in human is about
Responda
  • 140 ml
  • 50 ml
  • 70 ml
  • 100ml
  • 200ml

Questão 46

Questão
Major functions of the lymphatic system are?
Responda
  • provide route for return of extracellular fluid
  • act as drain off for inflammatory response
  • render surveillance, recognition , and protection against foreign materials via lymphocytes, phagocytes, and antibodies
  • a, and c
  • a, b, and c

Questão 47

Questão
Blood pressure is the measure of:
Responda
  • pressure exerted by the blood on the walls of the blood vessels
  • pressure exerted by the blood on the arteries
  • pressure exerted by the blood on the veins
  • pressure exerted by the blood on the aorta
  • none of the above

Questão 48

Questão
Systolic Pressure is:
Responda
  • an average of 120 mm Hg
  • lowers steadily during ventricle systole
  • the highest when blood is being pumped out of the left ventricle into the aorta
  • an average of 80 mm Hg
  • a, and c

Questão 49

Questão
The working myocardium:
Responda
  • is a functional syncitium
  • is comprised of cells whose cytoplasm communicates
  • plays the role of pacemaker of the heart
  • is comprised of cells, connected by structures that impede the ion flow
  • reacts to threshold irritants with different number of excited fibers

Questão 50

Questão
The heart rate at rest is:
Responda
  • 100 - 140 beats.min-1
  • 40 - 60 beats.min-1
  • approximately 50 beats.min-1
  • 60-90 beats.min-1
  • 20-40 beats.min-1

Questão 51

Questão
The full compensatory pause is typical of:
Responda
  • the atrial extrasystoles only
  • both the atrial and the ventricular extrasystoles
  • the ventricular extrasystoles only
  • extrasystoles during atrial fibrillation
  • extrasystoles during atrial flutter

Questão 52

Questão
The duration of the cardiac cycle depends on:
Responda
  • stroke volume
  • the time one systole to occur
  • the time one diastole to occur
  • the heart rate
  • the cardiac paused

Questão 53

Questão
The rhythm of the heart is determined by:
Responda
  • the bundle of His
  • the atrioventricular node
  • the sinus node
  • the Purkinje fibers
  • the Ieft and right bundle branches

Questão 54

Questão
The increased heart rate is called:
Responda
  • tachipnoe
  • bradycardia
  • atrial fibrillation
  • atrial flutter
  • tachycardia

Questão 55

Questão
When the rhythm is determined by the AV node, the heart rate is:
Responda
  • 60-90 beats.min-1
  • 20-40 beats.min-1
  • approximately 75 beats.min-1
  • 40-60 beats.min-1
  • 8-120 beats.min-1

Questão 56

Questão
Automaticity is characteristic of:
Responda
  • the cardiac muscle only
  • the striated muscles
  • some neurons and smooth muscle cells
  • all excitable tissues
  • the smooth muscle cells only

Questão 57

Questão
The action potential of the cardiomyocytes passes through:
Responda
  • slow depolarization and quick repolarization
  • rapid depolarization and slow repolarlzation
  • quick de- and repolarizations
  • slow de- and repolarizations
  • period of current electrical activity, expressed as slow waves and spike potentials

Questão 58

Questão
P wave of the electrocardiogram reflects:
Responda
  • repolarization of the atria
  • depolarization of the ventricles
  • depolarization of the atria
  • hyperpolarization of the atria
  • the time necessary for the impulse originating in SA. node to reach the Purkinje fibers

Questão 59

Questão
Asynchronic contraction of the ventricles:
Responda
  • is a phase of the ventricular systole
  • is a phase of the ventricular diastole
  • begins with closing the S.L. valves
  • begins with opening the S.L. valves
  • begins with opening the A.V. valves

Questão 60

Questão
In the complete atriovenrticular block:
Responda
  • the conductivity at the bundle of His is fully interrupted
  • there is a complete independence of the atrial and ventricular ECG stages
  • the atrial waves indicate normal heart rate, but the rate of ventricular ones is 20-40 beats.min-1
  • the duration of PQ interval is 0.12-0.20 s
  • a, b, and c

Questão 61

Questão
The stroke volume of the heart at rest is:
Responda
  • 60 - 90 beats.min-1
  • approximately 70 ml
  • 5.2 l
  • 0.500 I
  • 100-140 mmHg

Questão 62

Questão
The electrical axes of the heart is determined by:
Responda
  • the vectorial sum of QRS complexes in the standard leads
  • the vectorial sum of QRS complexes in the precordial leads
  • the vector's direction of the electrical forces of the ventricular muscle tissue
  • the supine or straight position of the body
  • the vector's direction of the electrical forces of the atrial muscle tissue

Questão 63

Questão
The augmented unipolar leads are
Responda
  • 1st, 2nd and 3rd
  • aVR, aVL and aVF
  • answers a, and b
  • V1, V2, V3, V4, V5 and V6
  • b, and d

Questão 64

Questão
The auscultation of the mitral valve is performed at:
Responda
  • 2nd sternal intercostal space, right of the sternum
  • 5th intercostal space, 2 cm inside of the medioclavicular line
  • 4th sternal intercostal space, right of the sternum
  • 2nd sternal intercostal space, left of the sternum
  • 3rd sternal intercostal space, left of the sternum

Questão 65

Questão
The phase 'plateau' of the cardiomyocytes action potentials is due to:
Responda
  • outflow of K+ from the cells
  • inflow of Na+ into the cells
  • inflow of K+ into the cells
  • slow inflow of Ca2+ into the cells
  • inflow of Na+ into the cells and outflow of K+ from the cells

Questão 66

Questão
The extrasystoles are:
Responda
  • increased heart rate of 250-230 imp-min-1
  • disturbances in conductivity
  • disturbances in excitability
  • extraordinary, only currently interrupting the cardiac rhythm, contractions of the cardiac muscle
  • c, and d

Questão 67

Questão
The electrical axes of the heart is of the indifferent type when the angle with the isoelectric line is:
Responda
  • +60 to +90 degrees
  • +30 to +60 degrees
  • from -90 degrees upward
  • +30 to -30 degrees
  • from -30 degrees downwards

Questão 68

Questão
Which of the following is not a vasoconstrictor:
Responda
  • norepinephrine
  • epinephrine
  • serotonin
  • angioitensin II
  • kinins

Questão 69

Questão
At rest the diastolic arterial pressure is:
Responda
  • 90-95 mmHg
  • 140-160 mmHg
  • 60-90 mmHg
  • 100-140 mmHg
  • 75 mmHg

Questão 70

Questão
Which of the following doesn't affect blood pressure:
Responda
  • cardiac output (C.O.)
  • minute respiratory volume
  • viscosity of blood
  • total peripheral vessel resistance
  • the volume of blood

Questão 71

Questão
Throughout the isovolumetrtc relaxation of the ventricles:
Responda
  • A.V. valves are opened, S.L. valves - opened
  • A.V. valves are closed, S.L. valves - opened
  • A.V. valves are opened, S.L. valves - closed
  • A.V. valves are closed, S.L. valves - closed
  • None of the above

Questão 72

Questão
The first heart sound is:
Responda
  • systolic, result of the ventricular contractions
  • systolic, result of the A.V. valves closing
  • systolic, result of the S.L valves closing
  • diastolic, result of the A.V. valves closing
  • a, and b

Questão 73

Questão
Cardiac output (C.O.) depends on:
Responda
  • vital capacity (VC)
  • stroke volume (SV)
  • heart rate (HR)
  • the preload and afterload
  • b, c and d

Questão 74

Questão
The intracardial regulation of the heart is carried out by:
Responda
  • integrated reflexes
  • neural regulatory mechanisms
  • humoral factors
  • adaptation to changes in venous return or resistance in the aorta
  • the automaticlty

Questão 75

Questão
The heart stops in diastole because of:
Responda
  • increased level of Ca2+ in the extracellular fluid
  • increased levels of catecholamines
  • increased levels of glucocorticoids
  • increased concentration of K+ the extracellular fluid
  • increased secretion of T3 and T4

Questão 76

Questão
The peripheral chemoreceptors trigger:
Responda
  • pressor and depressor reflexes
  • pressor reflexes only
  • the quick regulation of arterial blood pressure
  • depressor reflexes only
  • Hering-Breuer reflex

Questão 77

Questão
The pulse pressure is:
Responda
  • closer in value to the systolic than to the diastolic pressure
  • mean arithmetic of systolic and diastolic pressures
  • closer in value to the diastolic than to the systolic pressure
  • the difference between systolic and diastolic pressure
  • one third of the mean arterial pressure

Questão 78

Questão
The cardiovascular center is situated in:
Responda
  • hypothalamus
  • mesencephalon
  • the cortex
  • medulla oblongata
  • C8 - Th1-2 spinal cord segments

Questão 79

Questão
In the pulmonary circulation blood leaves the:
Responda
  • right ventricle and goes directly to the aorta
  • right ventricle and moves to the lungs
  • right atrium and goes directly to the left ventricle
  • right atrium and goes directly to the lungs
  • left ventricle and moves to the lungs

Questão 80

Questão
In the systemic circulation, blood leaves the:
Responda
  • left ventricle and goes directly to the aorta
  • right ventricle and goes directly to the aorta
  • right ventricle and moves to the lungs
  • lungs and moves to the left atrium
  • right atrium and goes directly to the lungs

Questão 81

Questão
The cardiac cycle includes all of the following events except:
Responda
  • the movement of impulses from the SA node to all regions of the heart wall
  • the closing and opening of the heart valves during each heart beat
  • the number of times the heart beats in one minute
  • the changes in pressure gradients in all chambers of the heart
  • the changes in blood volume in all chambers of the heart

Questão 82

Questão
Which of the following chemicals does not regulate blood pressure?
Responda
  • ADH
  • Atrial natriuretic peptide
  • Angiotensin II
  • Nitric acid
  • Epinephrine

Questão 83

Questão
Exchange of nutrients and gases between the blood and tissue cells is the main function of:
Responda
  • arterioles
  • arteries
  • veins
  • capillaries
  • venules

Questão 84

Questão
Arterial blood pressure increases in response to all but which of the following?
Responda
  • increasing stroke volume
  • increasing heart rate
  • rising blood volume
  • falling blood volume
  • all of the above

Questão 85

Questão
The inferior vena cava brings blood from the lower regions of the body empties into the:
Responda
  • left atrium
  • right atrium
  • aorta
  • left ventricle
  • right ventricle

Questão 86

Questão
The pacemaker of the heart is the;
Responda
  • Purkinje fibers
  • The bundle branches
  • Bundle of His
  • AV node
  • SA node

Questão 87

Questão
The tricuspid valve is located between the:
Responda
  • right and left atria
  • right and left ventricles
  • right atrium and right ventricle
  • left atrium and left ventricle
  • right ventricle and the aorta

Questão 88

Questão
When the mitral valve closes, it prevents the backflow of blood from the:
Responda
  • left atrium into the left ventricle
  • left ventricle into the left atrium
  • right atrium into the right ventricle
  • left ventricle into the aorta
  • right ventricle into the pulmonary trunk

Questão 89

Questão
The vessels that carry oxygen to the myocardial cells are called:
Responda
  • aortic arteries
  • pulmonary arteries
  • pulmonary veins
  • coronary veins
  • coronary arteries

Questão 90

Questão
The myocardium functions as a functional syncytium due to:
Responda
  • the presence of striations in the myocardium
  • branching of myocardlal cells
  • the presence of gap junctions
  • the presence of desmosomes
  • higher concentration of Ca2+

Questão 91

Questão
Autorhythmic cardiac cells are found In all the following location except the:
Responda
  • SA node
  • Interatrial septum
  • Purkinje cells
  • AV node
  • His bundle

Questão 92

Questão
Coronary blood flow to the left ventricle increases during:
Responda
  • early systole
  • myocardial hypoxia
  • hypothermia
  • stimulation of parasympathetic nerves in the heart
  • AV block

Questão 93

Questão
Local metabolic activity is the chief factor determining the rate of blood flow to the:
Responda
  • heart
  • skin
  • glands
  • lung
  • kidney

Questão 94

Questão
The pressure:
Responda
  • drop along large veins is similar to that along large arteries
  • drop across the hepatic penal bed is similar to that across the splenic vascular bed
  • in the hepatic portal vein exceeds that in the inferior vena cava
  • drop across the vascular bed in the foot is greater when a subject is in the vertical than when he is in the horizontal position
  • in foot veins is higher when walking than when standing still

Questão 95

Questão
The second heart sound differs from the first heart sound in that it is
Responda
  • related to turbelence set up by valve closure
  • longer lasting than the first sound
  • higher in frequency
  • occasionally in split
  • heard when the ventricles are contracting

Questão 96

Questão
Pulmonary vascular resistance is
Responda
  • is equal to that offered by the systemic circuit
  • decreased when alveolar oxygen pressure fails
  • expressed in units of volume flow per unit time per unit pressure gradients
  • decreased during exercise
  • regulated reflexvely by sympathetic vasoconstrictor nerves

Questão 97

Questão
Veins:
Responda
  • contain most of the blood volume
  • have a histaminergic vasodilator innervation
  • receive nutrition from vas vasorum arising from their lumen
  • respond to distension by dilation of their smooth muscle
  • do not contain valves

Questão 98

Questão
In the heart:
Responda
  • the left atrial wall is about three times thicker than the right atrial wall
  • systolic contraction normally begins in the left atrium
  • excitation spreads directly from atrial muscle cells to ventricular muscle cells
  • atrial and ventricular muscle contracts simultaneously in systole
  • the contracting ventricles shorten from apex to base

Questão 99

Questão
When measuring blood pressure by the auscultatory method:
Responda
  • the sounds that are heard are generated in the heart
  • the cuff pressure at which the first sounds are heard indicate systolic pressure
  • the cuff pressure at which the loudest sounds are heard indicate diastolic pressure
  • systolic pressure estimations tend to be lower than those made by the palpatory method
  • wider cuff's are required for smaller arms

Questão 100

Questão
The absolute refractory period in the ventricles:
Responda
  • is the period when the ventricles are completely still excitable
  • corresponds to the period of ventricular depolarization
  • corresponds approximately to the period of ventricular relaxation
  • is shorter than the corresponding period in atrial muscle
  • decreases during parasympathetic stimulation of the heart

Questão 101

Questão
Vascular resistance:
Responda
  • increases by 50 per cent When the vascular radius is halved
  • is related to the thickness of the wall of the vessel
  • is related to the vessel’s length
  • is affected by blood Hb concentration
  • is greater in the capillary bed than in the arteriolar bed

Questão 102

Questão
Sympathetic drive to the heart is increased:
Responda
  • in exercise
  • in relaxed position
  • in normotension
  • when parasympathetic drive is decreased
  • during a vasovagal attack

Questão 103

Questão
Hyperaemia in skeletal muscle during exercise is normally associated with:
Responda
  • release of sympathetic vasoconstrictor tone in the exercising muscles
  • capillary dilation due to relaxation of capillary smooth muscle
  • a fall in arterial pressure
  • reflex vasoconstriction in other vascular beds
  • an increase in venous pressure

Questão 104

Questão
Sinuatrial node cells are:
Responda
  • found in both atria
  • innervated by the somatic nerves
  • unable to generate impulses when completely denervated
  • connected to the AV node by fine bundles of purkinje tissue
  • able to generate impulses because their membrane potential is unstable

Questão 105

Questão
The first heart sound corresponds in time with:
Responda
  • closure of the aortic and pulmonary valves
  • the P wave of the electrocardiogram
  • a decline in atrial pressure
  • a rise in ventricular pressure
  • the A wave in central venous pressure

Questão 106

Questão
The velocity of blood flow:
Responda
  • in capillaries is low because they offer high resistance to flow
  • in veins is greater than in venules
  • can fall to zero in the ascending aorta during systole
  • is lower towards the centre of large blood vessels than at the periphery
  • in the circulation falls as the haematocrit falls

Questão 107

Questão
The strength of contraction of left ventricular muscle increases when:
Responda
  • end-diastolic ventricular filling pressure
  • serum potassium levels rise
  • blood calcium levels fall
  • blood magnesium levels fall
  • peripheral resistance is decreased

Questão 108

Questão
During isometric ventricular contraction:
Responda
  • the entry and exit valves of the ventricle are closed
  • pressure in the aorta rises
  • pressure in the atria falls
  • left coronary blood flow is going up
  • the rate of rise in pressure is greater in the right than in the left ventricle

Questão 109

Questão
Cardiac output:
Responda
  • is normally expressed as the output of one ventricle in liters/minute
  • is about 2.0 l at rest
  • is about 10.0 l at rest
  • rises in a cold environment
  • does not increase in exercise following denervatlon of the heart

Questão 110

Questão
In the brachial artery:
Responda
  • Pulse waves travel at the same velocity as blood
  • Pulse pressure falls with decreasing elasticity of the wall
  • Pressure rises markedly when the artery is occluded distally
  • Pressure falls when the arm is raised above head level
  • Pulse pressures have a smaller amplitude than aortic pulse pressures

Questão 111

Questão
Arterioles offer more resistance to flow than other vessels since they have:
Responda
  • thicker muscular walls
  • richer sympathetic innervation
  • smaller internal diameters
  • a smaller total cross-sectional area
  • a greater pressure drop along their length

Questão 112

Questão
In the denervated heart, left ventricular stroke work increases when:
Responda
  • the end-diastolic length of the ventricular fibres increase
  • peripheral resistance decreases
  • blood volume falls
  • right ventricular output decreases
  • the veins dilate

Questão 113

Questão
With increasing distance from the heart, arterial:
Responda
  • walls contain relatively more smooth muscle than elastic tissue
  • flow has a greater tendency to be turbulent
  • mean pressure tends to decrease slightly
  • pulse pressure tends to increase slightly
  • pO2 falls appreciably

Questão 114

Questão
In the estimation of cardiac output using the Fick principle:
Responda
  • pulmonary blood flow is measured
  • the pO2 of arterial and mixed venous blood are measured
  • oxygen uptake is estimated from alveolar pO2 measurements
  • pulmonary arterial blood is sampled to measure the oxygen in venous blood
  • pulmonary venous blood is sampled to measure the oxygen in arterial blood

Questão 115

Questão
Systemic hypertension may be caused by:
Responda
  • hypoxia due to chronic respiratory failure
  • excessive secretion of aldosterone
  • excessive secretion of insulin
  • myocardial thickening (hypertrophy) of the left ventricle
  • the rapid cardiac action of ventricular fibrillation

Questão 116

Questão
Peripheral differs from central circulatory failure in that:
Responda
  • hypovolaemia is unusual
  • it leads to underperfusion of the tissues
  • cardiac output is usually normal
  • central venous pressure is high
  • ventricular function is usually normal

Questão 117

Questão
In atrial fibrillation:
Responda
  • the electrocardlagram shows no evidence of atrial activity
  • ventricular rate is lower than atrial rate
  • respiratory sinus arrhythmia can usually be seen
  • the ventricular rate is higher than atrial rate
  • the QRS complexes have an abnormal configuration

Questão 118

Questão
Pain due to poor coronary blood flow (angina) may be relieved by:
Responda
  • Cutting the parasympathetic nerve trunks supplying the heart
  • Infecting CaCl2
  • Providing the patient with a cold environment
  • β-adrenoceptor stimulating drugs
  • Drugs causing peripheral vasodilation

Questão 119

Questão
Aortic valve incompetence may cause:
Responda
  • increase in arterial pulse pressure
  • systolic murmurs in the aortic valve area
  • hypertrophy of right ventricular muscle
  • decreased myocardial blood flow
  • right ventricular failure

Questão 120

Questão
Ventricular extrasystoles:
Responda
  • are usually associated with a normal QRS complex
  • from the same focus have similar QRS complexes
  • usually occur following a compensatory pause
  • can‘t be detected by ECG
  • indicate serious heart disease

Questão 121

Questão
Pulmonary embolism (blood clots impacting in lung blood vessels) usually decreases:
Responda
  • pulmonary vascular resistance
  • left atrial pressure
  • right atrial pressure
  • ventilation to perfusion ratios in the affected lung
  • pO2 in pulmonary venous blood

Questão 122

Questão
Hardening of the arterial walls tends to raise:
Responda
  • Arterial compliance
  • Systolic arterial pressure
  • Diastolic arterial pressure
  • Peripheral resistance
  • The frequency of breathing

Questão 123

Questão
Left ventricular failure tends to cause an increase in:
Responda
  • right atrial pressure
  • Ieft ventricular ejection fraction
  • pulmonary capillary pressure
  • lung compliance
  • pulmonary oedema when the patient stands up

Questão 124

Questão
In otherwise healthy people, local tissue death follows obstruction of:
Responda
  • an internal carotid artery
  • a renal artery
  • a femoral artery
  • a brachial artery
  • the hepatic portal vein

Questão 125

Questão
The part of the circulation pumping blood to and from the lungs is known as the _____ circulation.
Responda
  • systemic
  • pulmonary
  • coronary
  • respiratory
  • hepatic

Questão 126

Questão
The plateau phase of the action potential in contractile myocardiocytes is due to:
Responda
  • the slow movement of Na+ across the cell membrane
  • the influx of Ca2+
  • the increased membrane permeability to K+
  • the increased membrane permeability to Na+
  • a decrease in Ca2+ diffusing across membrane

Questão 127

Questão
The valve between the right ventricle and the vessel that leaves it is the _____ valve.
Responda
  • tricuspid AV
  • bicuspid AV
  • mitral
  • pulmonary semilunar
  • aortic semilunar

Questão 128

Questão
If the connections between the parasympathetic division of the ANS and the heart were cut, then
Responda
  • heart rate would decrease
  • stroke volume would decrease
  • cardiac output would decrease
  • heart rate would increase
  • heart activity would remain unchanged

Questão 129

Questão
Fenestrated capillaries:
Responda
  • have pores in their walls
  • are located in most tissue
  • permit only one-way exchange of materials
  • have a layer of smooth muscle in their walls
  • are found in the liver and kidneys

Questão 130

Questão
Absolute refractory period in the heart:
Responda
  • corresponds to the duration of relaxation
  • lasts till half of cardiac contraction
  • shorter than refractory period in skeletal muscle
  • lasts till cardiac contraction
  • last only 10 ms

Questão 131

Questão
First heart sound occurs during the period of:
Responda
  • isometric relaxation
  • isotonic relaxation
  • isovolumetric contraction
  • isovolumetric relaxation

Questão 132

Questão
Which of these vessels does not have sympathetic control:
Responda
  • cerebral
  • splanchnic
  • cardiac
  • cutaneous
  • muscle

Questão 133

Questão
Blood brain barrier is made up of:
Responda
  • astrocytes
  • oligodendrocytes
  • oligodendroglia
  • microglia
  • others

Questão 134

Questão
Positive bathmotropic effect on heart is produced by:
Responda
  • stimulation of vagus nerve
  • stimulation of sympathetic nerves
  • atropin
  • sectioning of vagus
  • K+

Questão 135

Questão
Which of the following conducting systems has the slowest conducting velocity:
Responda
  • SA node
  • Atrial muscle
  • Purkinje fibres
  • AV node
  • Hiss bundle

Questão 136

Questão
In heart, within physiological limits the force of contraction is directly proportional to the:
Responda
  • Pacemaker activity
  • AV nodal delay
  • Initial length of the cardiac muscle
  • Respiratory rate
  • ST-segment

Questão 137

Questão
The diacrotic notch on aortic pressure curve is caused by:
Responda
  • closure of mitral valve
  • closure of tricuspid valve
  • closure of atrial valve
  • closure of pulmonary valve
  • opening the atrial valve

Questão 138

Questão
The PR interval of ECG corresponds to:
Responda
  • ventricular repolarization
  • atrial repolarization and conduction through AV node
  • repolarization of AV node and bundle of His
  • depolarization of SA node

Questão 139

Questão
Increased vagal tone causes:
Responda
  • hypertension
  • tachycardia
  • bradycardia
  • increase in cardiac output
  • increase in stroke volume

Questão 140

Questão
Which of the following is not increased during exercise;
Responda
  • stroke volume
  • total peripheral resistance
  • systolic BP
  • heart rate
  • muscle blood flow

Questão 141

Questão
Which of the following takes longest time to return to normal after 1L of blood is removed from a normal individual:
Responda
  • number of RBC in peripheral blood
  • plasma volume
  • renin secretion
  • blood pressure
  • number of WBC in peripheral blood

Questão 142

Questão
In a patient with mitral stenosis one would expect to hear:
Responda
  • continuous murmur
  • a systolic murmur loudest over the base of heart
  • a diastolic murmur loudest over the apex of heart
  • a diastolic murmur loudest over the base of heart
  • systolic murmur over the apex of heart

Questão 143

Questão
The ‘S' wave in ECG is below isoelectric line because of:
Responda
  • repolarization of ventricles
  • change in direction of the impulse when the base of the ventricles are getting depolarised
  • depolarisation of apex of heart
  • repolarisation of apex of heart
  • depolarisation of atria

Questão 144

Questão
Lymph flow from the foot is:
Responda
  • increased when an individual rises from the supine to standing position
  • increased by massaging the foot
  • increased when capillary permeability is decreased
  • decreased by exercise
  • decreased by massaging the foot

Questão 145

Questão
The "T" wave in ECG is above the isoelectric line because of:
Responda
  • depolarisation of ventricles
  • depolarisation of bundle of His
  • change in the direction of repolarisation from the wave of depolarization of the ventricles
  • repolarisation of purkinje fibres
  • depolarisation of atria

Questão 146

Questão
Restoration of the blood volume after haemorrhage is aided by:
Responda
  • contraction of venous reservoirs
  • a fall in capillary pressure in certain vascular beds
  • arteriolar vasodilation
  • mobilization of intracellular fluid into the circulation
  • in increase in the osmotic pressure of the plasma proteins

Semelhante

Epithelial tissue
Morgan Morgan
Renal System A&P
Kirsty Jayne Buckley
Physiology / Intro psychology
Molly Macgregor
Introduction to Therapeutic Physical Agents
natalia m zameri
Malignancies
Mark George
General Physiology of the Nervous System Physiology PMU 2nd Year
Med Student
Blood MCQs Physiology PMU 2nd Year
Med Student
Muscles- Physiology MCQs PMU- 2nd Year
Med Student
Thorax- Anatomy 2nd Sem, 2nd Year- PMU
Med Student
General Pathoanatomy Final MCQs (401-519)- 3rd Year- PMU
Med Student
Regulation of Body Temperature- Physiology 2nd year- PMU
Med Student