This is called peer review. A peer is a person of at least equal standing in the area of intellect to the person being reviewed.
Probably the animals and what the animals live in.
Answer:
Cell Wall: This is the rigid outermost layer of a plant cell. It makes the cell stiff -providing the cell with mechanical support - and giving it protection. Animal cells do not have cell walls. Cell Membrane: This is a protective layer that surrounds every cell and separates it from its external environment.
