Circulatory Pathways
Circulatory Pathways: Overview
This topic consists of various concepts like Heart of Amphibia,Atrial Systole,Open Circulatory System, etc.
Important Questions on Circulatory Pathways
Tricuspid valve is found in between
Given below is the ECG of a normal human. Which one of its components in human is correctly interpreted below
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
Splenic artery arises from
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.
Match List I with List II.
| List I | List II |
| A. P-wave | I. Beginning of systole |
| B. Q-wave | II. Repolarisation of ventricles |
|
C. QRS complex |
III. Depolarisation of atria |
| D. T-wave | IV. Depolarisation of ventricles |
Choose the correct answer from the options given below:
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).
What is stroke volume? What is its relation with cardiac output ?
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.
Why the "Heart of the heart" is called SA node?
Give scientific reason.
Closed circulation is more efficient than open circulation.
If the valves in heart are not present what would happen?
Select the correct statement:
