What is the difference between the cell membrane and cytoplasm in an animal cell?
A great difference.
The cell membrane surrounds the cytoplasm. The cell membrane is made of a phospholipid bilayer that is only 7 nm thick. It is responsible for controlling what can enter and exit the cell.
The cytoplasm, however is a jelly like material. Cytoplasm is where all the metabolic reactions of the cell take place in organelles, eg, respiration takes place in the mitrochondria (an organelle in the cytoplasm).
Basically, the cell membrane protects the cell's contents, which is basically your cytoplasm.