1. Unit 2: Cells

2. The Cell Theory
The cell is the basic unit of structure and function (a.k.a. – life)
All living things are made up of 1 or more cells
Cells come from other, preexisting cells (a.k.a. – reproduction)

3. Scientists Involved in the Cell Theory
1. Hooke
1st person to describe cells. Built microscope in 1665.
2. Van Leeuwenhoek
Discovered the diversity of cells 1673.
3. Schleiden and Schwann ( )
All organisms are made of one or more cells.
The cell is the basic unit of all living things.
4. Later (1858) Virchow added
All cells come from existing cells.

4. What is a cell?
It is the smallest unit of life that carries out life functions
Animal Cell
Plant Cell

5. Two Types of Cells
Prokaryotic
Eukaryotic

6. Prokaryotic Do not have structures surrounded by membranes
Few internal structures
One-celled organisms, Bacteria

7. Eukaryotic Contain organelles surrounded by membranes
Most living organisms
Plant Cell
Animal Cell

8. Typical” Animal Cell

9. “Typical” Plant Cell

10. What’s Inside? Organelles
tiny structures within a cell that perform specific jobs to keep the cell alive

11. Important Organelles Cytoplasm - gel-like material inside cells

12. Important Organelles – Continued…
Cell Membrane - protects cell and gives it shape and controls what enters and leaves the cell.
Cell Membrane

13. Important Organelles – Continued…
Nucleus - directs cell activities (brain)
Nucleus

14. Important Organelles – Continued…
Endoplasmic Reticulum (ER) - movement of materials throughout cell ER

15. Important Organelles – Continued…
Ribosome - makes proteins
Ribosomes

16. Important Organelles – Continued…
Mitochondria - the powerhouse of the cell (converts food into energy for the cell)
Mitochondria

17. Important Organelles – Continued…
Chromatin/Chromosomes (DNA) - contains genetic information (inside the nucleus)
Chromatin

18. Important Organelles – Continued…
Chloroplast - takes energy from the sun and makes food for the PLANT cell (not found in Animal Cells)
Chloroplast

19. Important Organelles – Continued…
Cell Wall - supports and protects PLANT cells (not found in animal cells)
Cell Wall

20. Important Organelles – Continued…
Vacuole - storage of food and water
Vacuole

21. Important Organelles – Continued…
Golgi Body - packages and moves proteins
Golgi Body

22. Important Organelles – Continued…
Lysosome - digests wastes
Lysosome