1673-Anton von
Leeuwenhoek
observed living cells through a
microscope, called them
________________________.
1665-Robert Hooke
Examined cork (dead tree bark)
under a microscope.
1838-Matthias Schleiden
Used the term ____________ to
describe the tiny boxes he saw.
empty boxes he saw
Cell Theory is based on
the work of several
scientists who
discovered three basic
characteristics of all
cells and organisms.
The cell theory is fundamental to the study of organisms
and the basics of life science.
 All organisms are made up of one or more cells.
 The cell is the basic unit of all organisms.
 All cells come from existing cells.
1858-Rudolf Virchow
concluded all cells come from
_____________________ cells
discovered ____________________
______________________________
______________________________
______________________________
______________________________
1839-Theodor Schwann
found that animals are made of cells and
all organisms are made of
______________ or _______________
cells.
Cells are basic unit of __________