Human Circulatory System
Human Circulatory System: Overview
This Topic covers sub-topics such as Heart, Human Heart, Pacemaker, Veins, Artery, Blood Vessels, Cardiac Muscles, Tricuspid Valve, Pericardium, Semilunar Valves, Human Circulatory System, Purkinje Fibres, Bicuspid Valve, Atria and, Ventricles
Important Questions on Human Circulatory System
Tricuspid valve is found in between

Arteries are best defined as the vessels which:

If due to some injury, the chordae tendinae of the tricuspid valve of the human heart is partially non-functional, what will be the immediate effect?

In humans, blood passes from the post caval to the diastolic right atrium of heart is due to

The cardiac pacemaker in a patient fails to function normally. The doctors find that an artificial pacemaker has to be grafted in him.It will be grafted at which of the site?

Bundle of His is a network of:

Contraction of the ventricle in the heart begins by the command from:

The correct route through which pulse-making impulse travels in the heart is


Blood capillaries are made of

Splenic artery arises from

A vein possesses a large lumen because

People living at sea level have around 5 million RBC per cubic millimiter of their blood whereas those living at an altitude of 5400 metres have around 8 million. This is because at high altitude.

Normal activities of the heart are regulated intrinsically, i.e., auto regulated by specialised muscles (nodal tissue), hence the heart is called myogenic. Read following statement and choose correct option for right statements?
(i) Mass of this tissue is seen in the lower left corner of the right atrium close to the atrio- ventricular septum called the sino-atrial node (SAN).
(ii) A bundle of nodal fibres, atrioventricular bundle (AV bundle) continues from the AVN which passes through the atrio ventricular septum is known as bundle of His.
(iii) Bundle of His immediately divides into a right and left bundle which form Purkinje fibres.
(iv) The nodal musculature has the ability to generate action potentials without any external stimuli, i.e., it is autoexcitable.
(v) The SAN can generate the maximum number of action potentials, i.e., 90-95 min.
(vi) Our heart normally beats 70-75 times in a minute (average 72 beats min).

How many of the following statements is/are wrong?
A. In human heart, the atrium and ventricle of the same side are separated by a thick, fibrous tissue called atrio-ventricular septum.
B. Heart is situated between the two lungs in the thoracic cavity.
C. When sino-atrial node gets affected, atrio-ventricular node takes over its functions and starts producing action potentials at the rate 70-75 min-1.
D. Purkinje fibres are modified nerve fibres.

What is vasomotor tone?

Select the correct statement:

Which valves are present at the starting of the aorta and pulmonary artery in the ventricles, respectively?

Bundle of His consists of
(A) Right bundle branch
(B) Left bundle branch
(C) Purkinje fibres
(D) AV bundle

