1. The Cellular Level

2. Basic unit of Life: Cells, every living thing is made up of cells.

3. 1. “Cells are the basic structural units of all plants and animals.
Cell Theory
1. “Cells are the basic structural units of all plants and animals.

4. 2. Cells are the smallest functioning units of life.
Cell Theory
2. Cells are the smallest functioning units of life.

5. 3. Cells are produced only by divisions of existing cells.
Cell theory
3. Cells are produced only by divisions of existing cells.

6. 4. Each cell maintains homeostasis.”
Cell Theory
4. Each cell maintains homeostasis.”
Essentials of anatomy and physiology: Second edition: Martini

7. Technology
Microscope
Staining
Electron microscope

8. Staining

9. Electron Microscope uses electrons to create an image of the target
two million times better resolution then light microscopes.

11. Size, Shape, and Number Cell SIZE varies, all are microscopic.
SHAPE varies considerably based on function.
Average: we have an average NUMBER of 60 trillion cells.

12. Differentiation
The process of cells becoming different and specialized.

13. Differentiation 1. Fertilization produces a single cell.
2. Start to divide.
3. Differentiate.
4. Example: Liver, neurons, fats:
Contain same genes, but some genes turned off and some turned on for transcription.