1. Tardigrade
  2. Question
  3. Biology
  4. Incorrect statements about the heart are I. The sino-atrial node (SAN) is present in the right top corner of the right atrium II. Ligamentum arteriosum connects the aorta and pulmonary trunk. III. Purkinje fibres constitute a portion of the bundle of His. IV. The pulmonary trunk connects the right ventricle to the lungs.

Q. Incorrect statements about the heart are
I. The sino-atrial node (SAN) is present in the right top corner of the right atrium
II. Ligamentum arteriosum connects the aorta and pulmonary trunk.
III. Purkinje fibres constitute a portion of the bundle of His.
IV. The pulmonary trunk connects the right ventricle to the lungs.

 1712  200 NTA AbhyasNTA Abhyas 2020Body Fluids and Circulation Report Error

Solution:

A patch of nodal tissue is present in the right upper corner of the right atrium called the sino-atrial node (SAN). Ligamentum arteriosum connects aorta and pulmonary trunk. It is formed by obliteration of ductus arteriosus in the foetus. A bundle of nodal fibres, atrioventricular bundle (AV bundle) continues from the AVN which passes through the atrio-ventricular septa to emerge on the top of the interventricular septum and immediately divides into a right and left bundle. These branches give rise to minute fibres throughout the ventricular musculature of the respective sides and are called purkinje fibres. These fibres alongwith right and left bundles are known as bundle of His.