NEET BIOLOGY

Detailed explanation-1: -The phylum Porifera comprises the sponges. Sponges are simple invertebrate animals that live in aquatic habitats. Although the majority of sponges are marine, some species live in freshwater lakes and streams.

Detailed explanation-2: -Invertebrates are sometimes (mistakenly) thought of as primitive because of their lack of developed organs. Their simple internal systems include respiratory systems such as gills or trachea and they often use an open circulatory system to pump their blood.

Detailed explanation-3: -Phylum Porifera is a group of simple animals that includes the sponges. Porifera have no internal organs, nervous tissue, circulatory system, or digestive systems, making them the most primitive of the multi-cellular animals.