Question

A body having meshwork of cells, internal cavities lined with food filtering flagellated cells and indirect development are the characteristics of phylum?

• A. Mollusca
• B. Coelenterata
• C. Porifera
• D. Protozoa

Answer 1

The correct option is C

Porifera

The correct option is C.

Explanation of correct option:

1. The phylum Porifera includes multicellular animals that are commonly called sponges. They exhibit the cellular level of organization; their body is a meshwork of cells.
2. Sponges possess a water transport system (canal) and an internal cavity (spongocoel).
3. The canal and spongocoel are lined by choanocytes (collar cells). Choanocytes are flagellated cells that help to filter water and food.
4. Sponges undergo indirect development. It is characterized by the presence of a larval stage which is morphologically different from the adult.

Explanation of incorrect option:

Option A:

1. The phylum Mollusca comprises bilaterally symmetrical and coelomate animals. Example: squid.
2. They are triploblastic and the level of organization is organ-system.

Option B:

1. The phylum Coelenterata (Cnidaria) includes aquatic animals that possess specialized cells called cnidoblasts. Example: corals.
2. They are diploblastic animals and exhibit tissue level of organization.

Option D:

1. Protozoans are eukaryotic, unicellular, and heterotrophs. Example: Amoeba.
2. They reproduce both sexually and asexually.

Final answer: Body having meshwork of cells, internal cavities lined with food filtering flagellated cells, and indirect development are the characteristics of phylum Porifera.