State the characteristics of animals belonging to phylum porifera.

Explanation

i.Animals belonging to phylum Porifera are multicellular and have an asymmetrical body.
ii.They have the simplest body plan amongst all multicellular organisms and are known as sponges.
iii. Most of these animals are marine and few are fresh water dwellers.
iv. Their body shows numerous pores called ostia and oscula. Water enters into the body through ostia and comes out through osculum.
v.They have special type of cells called collar cells.
vi.The members of this phylum are sedentary (do not show locomotion), as they remain attached to the substratum.
vii. Their body is supported by spicules or spongin fibres. These spicules are made up of calcium carbonate or silica.
viii. Poriferans reproduce asexually and/or sexually.
ix. They have the ability to regenerate. For e.g. Sycon, Euspongia, Hyalonema, Euplectella, etc.