4 Written questions
3 Multiple choice questions
- Gas exchange and excretion occur via diffusion across individual cell membranes.
- no true tissue
- 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 are choanocytes? → They lack tissues, organs, and organ system.
What kind of feeding? → intracellular
what do they lack? → They lack tissues, organs, and organ system.