What do cells in common?

Prokaryotic cells are cells where its organelles float around and have no defined nucleus (E.G. Amoebas). Eukaryotic cells have a defined nucleus and its organelles are fixed (do not move around). Plant cells have a membrane plus a cell wall (which gives the plant is strength and structure), animal cells have only a membrane. Everything else is similar. As for the last question, check out this website: a href="http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/E/Enzymes.html" rel="nofollow"http://users.rcn.com/jkimball.ma.ultrane…/a