Match the following related to the cardiac cycle. Column I Column II i Cardiac Cycle a 0 . 2 sec ii Atrial Systole b 0 . 4 sec iii Ventricular Systole c 0 . 1 sec iv Cardiac Diastole d 0 . 8 sec e 0 . 3 sec

i - d , ii - c , iii - e , iv - b

i - d , ii - c , iii - b , iv - e

i - b , ii - c , iii - e , iv - d

i - d , ii - a , iii - e , iv - b

EASY

Earn 100

Which structure in the heart is called pacemaker?

Important Questions on Body Fluids and Circulation

MEDIUM

Biology>Human Physiology>Body Fluids and Circulation>Circulatory Pathways

Doctors use a stethoscope to hear the sounds produced during each cardiac cycle. The second sound is heard when:

EASY

Biology>Human Physiology>Body Fluids and Circulation>Circulatory Pathways

Frog's heart when taken out of the body continues to beat for sometime.

Select the best option from the following statements:

(i) Frog is a poikilothermic

(ii) Frog does not have any coronary circulation

(iii) Heart is "myogenic" in nature

(iv) Heart is autoexcitable

EASY

Biology>Human Physiology>Body Fluids and Circulation>Circulatory Pathways

Match the following related to the cardiac cycle.

Column I		Column II
$(i)$	Cardiac Cycle	$(a)$	$0.2 \sec$
$(ii)$	Atrial Systole	$(b)$	$0.4 \sec$
$(iii)$	Ventricular Systole	$(c)$	$0.1 \sec$
$(iv)$	Cardiac Diastole	$(d)$	$0.8 \sec$
		$(e)$	$0.3 \sec$

HARD

Biology>Human Physiology>Body Fluids and Circulation>Circulatory Pathways

Give the location of the following valve within the human heart.

Tricuspid valve

EASY

Biology>Human Physiology>Body Fluids and Circulation>Circulatory Pathways

Which of the following is associated with decrease in cardiac output?

HARD

Biology>Human Physiology>Body Fluids and Circulation>Circulatory Pathways

Give the location of the following valve within the human heart.

Eustachian valve.

EASY

Biology>Human Physiology>Body Fluids and Circulation>Circulatory Pathways

Assertion (A): Pulmonary aorta in human embryo communicates with systemic aorta by a thin vessel called ductus arteriosus.
Reason (R): In the heart of the human embryo, oxygenated and deoxygenated blood is completely separated.

HARD

Biology>Human Physiology>Body Fluids and Circulation>Circulatory Pathways

What does the QRS wave indicate in ECG?

MEDIUM

Biology>Human Physiology>Body Fluids and Circulation>Circulatory Pathways

Assertion $(A)$ : Dub' is one of the sounds of the heart caused during a cardiac cycle.

Reason $(R)$ : The sound is due to closure of semilunar valves present at the bases of aortic arches.

MEDIUM

Biology>Human Physiology>Body Fluids and Circulation>Circulatory Pathways

Statement (S): The sinoatrial node is called 'Pace-maker'.

Reason (R): The sinoatrial node contains specialised cardiomyocytes and generates action potentials without any external stimuli.

The correct answer is