Question

Which one of the following is homologous to pituitary gland of vertebrates?

• A. Muller's organ of Amphioxus
• B. Subneural gland of Ascidian
• C. Both A and B
• D. None of the above

Answer 1

Answer: (C)

Both A and B

The pharynx of amphioxus is perforated by over 100-150 pharyngeal gill slits or stigmata, which are used to strain food particles out of the water. In cephalochordates, a vestibule lies in front of the pharynx that is guarded by the oral cirri. The vestibule contains ciliated tracts of wheeler organ or muller's organs, an excretory organ (Hatschek's nephridium), and a shallow groove (Hatschek's pit) that is probably homologous to the adenohypophysis in vertebrates. In ascidian or sea-squirts, the tunicate has very simple nervous systems, which could be represented as ganglion below the sub neutral gland, which was thought to produce substances similar to hypophyseal substances.

So, the correct answer is option C.