血液循环系统测试试卷Ⅲ(英文版,全部为选择题)

血液循环系统测试试卷

1、Which one of the following substances has not direct relation with the regulation of the local blood flow?

A、lactic acid

B、CO2

C、renin

D、prostaglandin

E、adenosine

2、Regarding the normal circuit for blood flow，pressure is lowest in the _________.

A、right atrium

B、capillaries

C、inferior vena cava(下腔静脉）

D、systemic arteries

E、arterioles

3、In a cardiac cycle，the aortic pressure is the lowest at ___.

A、the end of isometric contraction period

B、the end of isometric relaxation period

C、the atrial systole

D、the rapid filling period

E、the beginning of slow ejection

4、The mean circulatory filling pressure depends on the relation between

A、Athe arterial pressure and the peripheral resistance

B、the cardiac output and the peripheral resistance

C、the blood volumes and the capacity of circulatory system

D、the heart output and the arterial pressure

E、the venous return and the contractility of the heart

5、In the____ ，the conducting velocity of the excitation is the lowest

A、SA node

B、AV node

C、Purkinje cells

D、His bundle

E、Ventricular muscles

6、The resistance vessel is ________.

A、the large artery

B、the small artery and the arteriole

C、the capillaries

D、the small vein

E、the large vein

7、The effective refractory period of the ventricle is longer and lasts until the ___________.

A、the beginning of the systole

B、middle of the systole

C、beginning of the diastole

D、end of the diastole

E、none of the above

8、In the normal condition，the sensitivity of the baroreceptor reflex is the highest while the pressure in the carotid sinus changed between ___________.

A、30 mmHg and 50 mmHg

B、70 mmHg and 90 mmHg

C、90 mmHg and 110 mmHg

D、130 mmHg and 150 mmHg

E、150 mmHg and 170 mmHg

9、Vasodilation in the heart and skeletal muscles during exercise is primarily due to the effects of

A、alpha-adrenergic stimulation

B、beta-adrenergic stimulation

C、cholinergic stimulation

D、products released by the exercising muscle cells

E、none of above

10、The systolic pressure corresponds the aortic pressure at _______.

A、the end of the rapid ejection period

B、the end of the isovolumic contraction

C、the end of ventricle systole

D、the end of the atrial systole

E、the end of the isovolumic relaxation period

11、__________ of the systemic circulation is similar to that of the pulmonary circulation.

A、The systolic pressure

B、The diastolic pressure

C、The pulse pressure

D、The peripheral resistance

E、The cardiac output

12、QRS complex signifies______

A、depolarization of the atria

B、depolarization of the ventricles

C、systole of ventricles

D、systole of atria

E、diastole of ventricle

13、The physiological significance of delay in AV node is

A、making the ventricular muscles not to produce the complete tetanus

B、enhancing the contractility of cardiac muscles

C、lengthening the effective refractory period of the ventricular muscles

D、permitting completion of atrial systole before the ventricular systole

E、increasing the amplitude of the action potential in the cardiac muscles

14、Stimulation of cardiac sympathetic nerves will cause______.

A、a decrease in right atrial pressure and an increase in cardiac output

B、an increase in right atrial pressure and a decrease in cardiac output

C、an increase in left ventricular end systolic volume

D、an increase in the P-R interval

E、none of the above

15、AV valves open at ________.

A、the end of isometric contraction period

B、the beginning of the ventricular systole

C、the end of the slow ejection period

D、the beginning of isometric contraction period

E、the end of isometric relaxation period

16、The difference in blood pressure between ___________________ is the highest.

A、the ascending aorta and the radial artery

B、the great saphenous vein and the right atrium

C、the femoral artery (股动脉）and the femoral vein

D、the pulmonary artery and the left atrium

E、the descending aorta and the famoral artery

17、Hypoxia of cardiac muscles will make the coronary artery relax，which is due to _____.

A、H+

B、histamine

C、adenosine

D、prostaglandin

E、lactic acid

18、If a vessel were to dilate to twice its previous radius，and if pressure remained constant，blood flow through this vessel would

A、increase by a factor of 16

B、increase by a factor of 4

C、increase by a factor of 8

D、increase by a factor of 2

E、decrease by a factor of 2

19、Both ADH and aldosterone act to

A、increase urine volume

B、increase blood volume

C、increase total peripheral resistance

D、increase urine protein

E、produce all of these effects

20、The reason that the myocardial cell does not produce the complete tetanus is__________.

A、that it is controlled autorhythmically

B、that its effective refractory period is very long

C、due to its all or none contraction

D、due to its atrioventricular delay

E、due to its little reserve of calcium in its sarcoplasmic reticulum

21、The preload of the ventricle can be expressed as

A、end-diastolic volume of the ventricle

B、end-systolic volume of the ventricle

C、aortic pressure

D、the ventricular volume in the rapid ejection period

E、the ventricular volume in the isometric relaxation period

22、The cardiac output of healthy adult male at rest is

A、2－3L/min

B、4 －6 L/min

C、7 －8 L/min

D、9 －10 L/min

E、11 －12 L/min

23、The plateau phase of action potential in ventricular cells is formed by

A、Na+ influx and Cl- efflux

B、Na+ influx and K+ efflux

C、Na+ influx and Cl- influx

D、Ca2+ influx and K+ efflux

E、K+ efflux and Ca2+ efflux

24、 A rapid heart rate ________.

A、may cause a decrease in pulse pressure

B、will be accompanied by a prolonged phase 2 of an action potential in the ventricular cell

C、will likely be associated with a decrease in diastolic arterial pressure

D、is associated with a prolonged P-R interval

E、will likely be associated with a decrease in peripheral resistance

25、The cardiac index is equal to

A、stroke volume × body surface area

B、stroke volume/body surface area

C、cardiac output ×body surface area

D、heart rate × body surface area /cardiac output

E、heart rate × stroke volume/body surface area

26、Which one in the following statements regarding the cardiac cycle is false?

A、The antrum and the ventricle have a common relaxing period

B、The antrum and the ventricle have a common contracting period

C、The relaxing period is longer than the contracting period

D、The length of a cardiac cycle relates to the heart rate

E、When the heart rate increases，the relaxing period shortens evidently.

27、If stroke volume is 75ml/beat and heart rate is 80 beats /min，what is the cardiac output?

A、2.0 L/min

B、3.0 L/min

C、5.25L/min

D、1550 ml/min

E、6.0 L/min

28、Noradrenaline can shift the ventricular function curve _________.

A、upward and to left

B、downward and to right

C、upward and to right

D、downward to left

E、upward

29、The phase 0 of action potential in ventricular cells is formed by

A、Na+ influx

B、K+ efflux

C、Cl- influx

D、Ca2+ influx

E、Ca2+ efflux

30、Blood pressure can be buffered by____

A、venous return

B、heart rate

C、cardiac contractility

D、elasticity of aorta

E、rate of transfusion

31、In a cardiac cycle，the period from the closure of the semilunar valves to their next opening is equal to _________.

A、the isometric contraction period

B、the ejection period

C、the relaxing period

D、the sum of the isometric contraction period and the ejection period

E、the sum of the ventricular relaxing period and the isovolumic contraction period

32、The excitability of cardiac muscle cell in the supranormal period is higher than normal，so ____________.

A、conduction velocity of excitation is also faster than normal

B、the amplitude of the action potential is higher than normal

C、the velocity of the phase 0 of an action potential is faster than normal

D、the threshold intensity is lower than normal

E、the autorhythmicity is higher than normal

33、The diastolic pressure refl ects mainly______

A、stroke volume

B、heart rate

C、peripheral resistance

D、elasticity of aorta

E、blood volume

34、When the stroke volume and the peripheral resistance remain unchanged，a slow heart rate can increase the _________.

A、arterial systolic pressure

B、arterial diastolic pressure

C、arterial pulse pressure

D、mean arterial pressure

E、cardiac output

1~5、CAACB 6~10、BCCDA 11~15、EBDEE 16~20、CCABB 21~25、ABDAE 26~30、BECAD 31~34、EDCB