Question

These structures of human heart are functional in embryonic stage, but are non functional in adult stage.

• A. Valve of Thebesius, Mitral valve, Ductus Botalli
• B. Foramen Mannu, Eustachian valve, Ductus arteriosus
• C. Fossa ovalis, Mitral valve, Ligamentum arteriosum
• D. Foramen ovale, Eustachian valve, Ductus arteriosus

Hint:

Fetal heart structures like the foramen ovale, Ductus arteriosus, and Eustachian valve bypass the lungs before birth but become non-functional after birth as the lungs take over.

Answer 1

The Correct Option is D

We need to identify heart structures that function in the embryonic stage but become non-functional in adults.
In the fetus, the foramen ovale allows blood to pass from the right atrium to the left atrium, bypassing the lungs; it closes at birth, becoming the fossa ovalis, so it’s non-functional in adults.
The Eustachian valve directs blood toward the foramen ovale in the fetus but serves no purpose after birth.
The Ductus arteriosus shunts blood from the pulmonary artery to the aorta in the fetus, bypassing the lungs, and closes after birth, becoming the ligamentum arteriosum, making it non-functional in adults.
Let’s check the options: 
Option (1) includes the Mitral valve, which remains functional in adults.
Option (2) has “Foramen Mannu,” a likely typo, but assuming it means foramen ovale, the combination is correct, though “Mannu” is incorrect.
Option (3) includes Mitral valve and Ligamentum arteriosum (non-functional, but a remnant, not a functional structure in the fetus).
Option (4) correctly lists Foramen ovale, Eustachian valve, and Ductus arteriosus—all functional in the fetus, non-functional in adults.

Final Answer: The correct combination is Foramen ovale, Eustachian valve, and Ductus arteriosus, so the correct option is (4).