Which of the following is not a vestigial organ?

Question

Question

This question was previously asked in

RRB Pharmacist Previous Year Paper 2015

Answer 1

Correct Answer: Diaphragm

Rationale:

The diaphragm is a crucial muscle in the human body, primarily responsible for the process of respiration. It separates the thoracic cavity from the abdominal cavity and plays a vital role in the mechanics of breathing.
During inhalation, the diaphragm contracts and flattens, creating a vacuum that allows air to be drawn into the lungs. During exhalation, it relaxes and returns to its dome shape, helping to expel air from the lungs.

Explanation of Other Options:

Centriole

Rationale: Centrioles are involved in cell division, particularly in the formation of the spindle fibers that separate chromosomes during mitosis and meiosis. They are not considered vestigial as they play an active role in cell reproduction.

Molar Tooth

Rationale: While molar teeth are not entirely vestigial, the third molars (wisdom teeth) are often considered vestigial because they are not necessary for modern human diets and often cause dental issues, leading to their removal.

Appendix

Rationale: The appendix is often cited as a vestigial organ. It is a small, tube-like structure attached to the large intestine. While it may have had a digestive function in ancestral species, in modern humans, it has no essential function and can be removed without apparent consequences.

Conclusion:

Among the given options, the diaphragm is the only organ that is not vestigial. It plays a critical role in respiration, unlike the appendix, which is a classic example of a vestigial organ, and the wisdom teeth, which are often considered vestigial due to their reduced functionality and frequent complications.

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