Question

‘Organ of Bojanus' is found in
A. Chordata
B. Echinodermata
C. Annelida
D. Mollusca

Answer 1

Hint: Metanephridia serve the same function as nephridia of advanced organisms but are structurally different.

Complete answer:
1. The organs of Bojanus or Bojanus organs are excretory glands that serve the function of kidneys in some of the Mollusca.
2. In other words, these are metanephridia that are found in some molluscs, for example in the bivalves, sepia, octopus, mussels, etc.
3. The excretory system (organ of bojanus)of a mollusc, for example, bivalve consists of a pair of kidneys.
4. These are situated one of each side of the body below the pericardium.
5. Each kidney consists of 2 parts-

• a. A ventral glandular part which opens into the pericardium.

• b. Dorsal thin-walled ciliated urinary bladder.

Additional Information:
Some other molluscs have another type of organ for excretion called Keber’s organ.
The Bojanus organ is named after Ludwig Heinrich Bojanus, who first described it.

So, the correct answer is ‘Mollusca’.

Note: A metanephridium (meta means “after”) is a type of excretory gland found in many types of invertebrates such as annelids, arthropods, and molluscs. It typically consists of a ciliated funnel opening into the body cavity, or coelom connected to a duct which opens to the outside of the body.