Conducting System

Question 1

Mention site of SAN & AVN

Answer 1

S: at the junction of SVC and right atrium, near sup end of sulcus terminalis
A: lower part of right atrium near opening of coronary sinus, just above attachment of the septal cusp of tricuspid valve.

Question 2

The … is the only muscular connection between myocardium of atria amd ventricles

Answer 2

AV bundle (bundle of His)

Question 3

The site of division of the bundle of His

Answer 3

At the upper border of the mucular part of septum

Question 4

The right bund branch runs in ….. till base of ….

Answer 4

Moderator band

Anterior papillary muscle

Question 5

Describe nerve supply of heart

Answer 5

Through cardiac plexus:
S, from cervical and upper thoracic sympathetic ganglia (3rd amd 4th)
Terminate on SAN, AVN, cardiac muscle fibers and coronary arteries
P, from 2 vagi, terminate on all previous ex cardiac muscle fibers