Question

What are sponges composed of?

1) Spongin and make up 80%
2) Calcium carbonate and make up 20%
3) Silica and make up 50%
4) Collagen and make up 30%

Answer 1

Sponges are composed of collagen and silica-rich spicules that provide structural support to their bodies.

Step-by-step explanation:

Sponges are composed of collagen and some have silica-rich spicules. The spicules are tiny needles made of silica, calcium carbonate, or spongin that provide structural support to the sponge's body. These spicules can vary in composition depending on the class of the sponge, with some sponges producing calcium carbonate spicules, others producing siliceous spicules, and some containing both.