Question

A sponge, harmful to the oyster industry is
(a)Spongilla
(b)Euspongia
(c)Hyalonema
(d)Cliona

Answer 1

Hint: This sponge creates round holes in limestone or the shells of molluscs. The sponge itself is often visible as a rather featureless yellow or orange lump at the bottom of the hole. They are commonly known as a red boring sponge. It is found worldwide.

Complete answer:
Cliona is a genus of Demospongiae in the family Clionaidae. They are harmful to the oyster industry as it creates round holes on the shells of oysters. This sponge creates round holes up to 5 cm in diameter in the shells of molluscs, especially oysters. These sponges are common in Southern New England and in Narragansett Bay. They also live in the Bahamas and the western Atlantic ocean. They usually live in lagoons or in reefs. Red boring sponges can reproduce asexually and sexually. They can simply separate by mitosis, as single cells do, or they can release sperm into the water in hopes of them finding a female’s eggs. They may also attach their larvae onto mollusks like clams and mussels. This usually results in the death of the host. They then will begin to grow and colonize.

Additional Information: -Sponges are primitive multicellular animals. They have the cellular level of organization. The cells in their body do not form the tissues.
-All cells act more or less independently and show little coordination. They are mostly marine and asymmetrical. They are known for their well-developed water canal system.
-Their body is supported by a skeleton made of calcareous or siliceous spicules and spongin fiber. Different cells are found in sponges; namely pinacocytes, choanocytes, and amoebocytes.
So, the correct answer is 'Cliona'.

Note: - Pinacocytes form the protective layer of the body. Choanocytes maintain water current inside the body. Amoebocytes store reserve food.
- Sponges are believed to be evolved from flagellated protozoans. They are hermaphrodites with males and females in the same individual.
-They reproduce sexually and asexually. Asexual reproduction involves fragmentation, budding, and regeneration. Sexual reproduction involves internal fertilization and indirect development.