4 Written questions
3 Multiple choice questions
- no body cavity
- Extracellular protein fibers give structure and strength to the sponge body and spicules, spines made of silica or calcium carbonate, offer protection from predation.
3 True/False questions
What kind of feeding? → Sponges are sessile (sedentary), filter feeding animals
where does gas exchange occur? → Gas exchange and excretion occur via diffusion across individual cell membranes.
What are choanocytes? → They lack tissues, organs, and organ system.