An Englishman who used an early compound microscope to look at a thin slice of cork, a plant material. Under the microscope the cork seemed to be made of thousands of tiny empty chamber. Hooke called these chambers "cells" because they reminded him of a monastery's tiny rooms, which were called cells. He later published a book called Micrographia which contained his drawings of sections of cork that he saw using one of the first microscopes. 

A tradesman from Holland who used a single lens microscope to observe pond water. Leeukwenhoek observed tiny living organisms in drops of pond water through his simple microscope. He called these tiny organisms "animalcules". 

A German botanist that concluded that all plants are made of cells. 

REMEMBER THIS: Schleiden was "sliding" down the beanstalk and discovered that plants have cells. 

A German zoologist that concluded that all animal tissues are made of cells. 

REMEMBER THIS: Schwann = "Swan" (an animal made of cells) 

A German doctor who concluded that cells can only come from other existing cells.