I. Why Study Cells?

A. Body is made up of cells:1. RBC

2. Nerve Cells

3. Skin Cells

4. Muscle Cells

B. Some more examples

5. White Blood Cells

6. T Cells & B Cells

7. Reproductive Cells

8. Stem Cells

C. Certain Cells can make us sick

Bacterial Cells Cancer Cells Protists

II. History of Cell Biology

1. Zacharias Janssen

A. 1595 – invented 1st optical compound microscope

2. Robert HookeA. 1665 – used a light microscope to look at

non-living cork cells

3. Anton van Leeuwenhoek

A. Made microscopes with magnification 10x greater

B. Observed living cells

IV. Cell Theory

A. 150 years later….(early 1800’s)

B. Three German scientists developed a theory about cells from their observations.

CELL THEORY

1.) All living organisms are composed of one or more cells

2.) Cells are the basic units of structure and function in an organism.

3.) Cells come only from the reproduction of existing cells.

V. Microscopes

A. COMPOUND MICROSCOPE

B. STEREOMICROSCOPE

Gives 3D images of specimen

C. SCANNING ELECTRON MICROSCOPE (SEM)

1. Uses electrons instead of light to project surface image of specimen

D. TRANSMISSION ELECTRON MICROSCOPE (TEM)

1. Works like light microscope except uses electrons

Electron Microscopes

2. Can magnify up to 200,000 x