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In these following correct statement abo...

In these following correct statement 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 constituent a portion of the bundle of His .
IV. The pulmonary trunk connects the right ventricle to the lungs

A

I and IV

B

II and IV

C

I, III and IV

D

I, II and III

Text Solution

AI Generated Solution

The correct Answer is:
To determine which statements about the heart are correct, let's analyze each statement step by step. ### Step 1: Analyze Statement I **Statement I:** The sino-atrial node (SAN) is present in the right top corner of the right atrium. - The sino-atrial node (SAN) is indeed located in the upper wall of the right atrium, specifically at the junction where the superior vena cava enters the right atrium. Therefore, this statement is **true**. ### Step 2: Analyze Statement II **Statement II:** Ligamentum arteriosum connects the aorta and pulmonary trunk. - The ligamentum arteriosum is a remnant of the ductus arteriosus, which connects the aorta and pulmonary trunk during fetal development. After birth, this duct closes and becomes the ligamentum arteriosum. However, it is important to note that the ligamentum arteriosum does not function as a connection between the aorta and pulmonary trunk in the same way the ductus arteriosus did. Thus, this statement is **false**. ### Step 3: Analyze Statement III **Statement III:** Purkinje fibres constitute a portion of the bundle of His. - The Purkinje fibers are specialized fibers that arise from the bundle of His (AV bundle) and spread throughout the ventricles to facilitate contraction. However, they are not considered a part of the bundle of His itself; rather, they are branches that extend from it. Therefore, this statement is **false**. ### Step 4: Analyze Statement IV **Statement IV:** The pulmonary trunk connects the right ventricle to the lungs. - The pulmonary trunk does indeed arise from the right ventricle and branches into the right and left pulmonary arteries, which carry deoxygenated blood to the lungs for oxygenation. Thus, this statement is **true**. ### Conclusion After analyzing all four statements: - **True Statements:** I and IV - **False Statements:** II and III The correct statements about the heart are **I and IV**. ### Final Answer The correct statements about the heart are **I and IV**. ---
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