1. Tools and Procedures 1-4 Most scientists use the metric system when collecting data and performing experiments.

2. A Common Measurement System Metric System – is a system of collecting data. It is a decimal system of measurements whose units are scaled on multiples of 10 so it is easy to use. International System of Units is a revised version of the original metric system. (SI)

3. Basic Units of Measurements Mass - gram Volume -liter Length -meter

4. Analyzing Biological Data What is the simplest way to find out whether factors in an experiment changed or remained the same? Record your data on a table& make a graph.

5. Microscopes A microscope magnifies images that are too small to see.

6. The Difference Between Light & Electron Microscopes Light Microscopes produce images by focusing visible light rays. Electron Microscopes produce images by focusing beams of electrons

7. Microscopes Compound Microscope is a light microscope that is used in most schools to observe small living organisms. It allows light to pass through the specimen and uses 2 lenses to form an images. Two types of Electron microscopes are: Transmission& Scanning TEM-needs greater magnification; views dead cells and organisms. SEM-3-D; enlarged views of surfaces.

8. Laboratory Techniques A cell culture is a group of cells that develops from a single cell placed in a dish containing a nutrient solution. Cell fractionation is a technique in which cells are broken into pieces and different cell parts are separated for study. A centrifuge is an instrument that separates cell parts according to density.

9. Safety Always wash your hands after a lab because you my come into contact with organisms you cannot see. It is very important to follow safe practices and follow your teachers instructions.