Porifera

What defines Phylum Porifera?

Multicellular organisms with no true tissues or organs.

How do sponges differ from protozoa?

Sponges are multicellular, while protozoa are unicellular.

What is the significance of choanocytes in sponges?

They help in water flow and food capture.

What is the spongocoel?

The central cavity within a sponge's body.

What type of skeleton do sponges have?

Made of spongin fibers, siliceous or calcareous spicules.

What happens during asexual reproduction in sponges?

Buds or gemmules are formed.

What is the role of the oscula in sponges?

They are large openings for water to exit.

How do Calcarea sponges differ from Demospongiae?

Calcarea have calcareous spicules; Demospongiae have varied skeletons.

What type of canal system do leuconoid sponges have?

A complex canal system with many chambers.

What is the typical habitat of sponges?

Mostly marine environments, with some freshwater species.

What is the developmental stage of sponges called?

Amphiblastula or parenchymula larva.

What distinguishes Hexactinellida from other sponge classes?

They have siliceous spicules with six rays.

What is a characteristic feature of Demospongiae?

They contain the largest number of sponge species.

What type of symmetry do sponges exhibit?

Asymmetrical or radially symmetrical.

What is the function of amoebocytes in sponges?

They assist in nutrient distribution and waste removal.