1. Where do cells come from?

2. Cell Theory
 All living things are made of cells.
 Cells are the basic unit of life.
 Cells come from other cells.
Schwann – animal cells 1839
Schleiden – plant cells 1839
Virchow – cell come from pre-existing cells
1855

3. Where did these animals come
from?

4. What about these plants?

5. Characteristics of Living Things
 Go to your journal page and review list.

6. All Living Things
REPRODUCE

7. What would happen if a species
could no longer reproduce?

8. What would happen if a species
could no longer reproduce?
The species would
become EXTINCT.

9. Think about this:
 Where do cells come from?
 All organisms begin as one cell. As you
learned last week, every cell contains
organelles that have specific functions to
carry on all of life’s processes. If
reproducing is required for a species to
continue, then cells must reproduce.
 How do cells reproduce?

10. Model

11.  In unicellular (single celled) organisms,
the cell divides to make new versions of
itself. In multicellular organisms, the cells
divide and then specialize to become
different structures such as heart, brain,
lungs, etc.
 Every day, your skin cells die and replace
themselves by reproducing new ones.
They do this by division.

12.  This process of division is called
Mitosis. It occurs in multiple
stages or phases. You will learn the details
of this process in high school biology.
 However, today, we are going to observe
cells that are going through different stages
of the reproductive process called Mitosis.

13. One piece of paper.
Folded into 12 squares.

14. Microscopes

17. Summary
After completing this
investigation, where would you
say cells come from?
How do cells reproduce?

18. Summary
After completing this
investigation, where would you
say cells come from? Cells come
from other cells.
How do cells reproduce?

19. Summary
After completing this
investigation, where would you
say cells come from? Cells come
from other cells.
How do cells reproduce?
Cells divide.