9. Is a theory a guess?
No, a scientific guess is a
hypothesis. A theory is fact.
10. Cell Theory
•All living things are made up of
one or more cells
•The cell is the basic unit of
structure and function
•All cells arise from pre-existing
cells
11. Who came up with the Cell
Theory?
• Many different scientists over
many years
12. Why do we care?
• To understand how tissues work
• How organs function
• Cure disease, such as cancer
• Cloning
19. Bacteria Viruses
Cause disease Cause disease
Have DNA Have DNA
Replicate Replicate
Evolve Evolve
Living Nonliving
Made up of a
cell
Not made up of
a cell
