Ch.1-4 Tools and

Procedures

A Common Measurement System

Most scientists use the metric system when collecting data and performing experiments, so that other scientists can replicate their experiments accurately.

Metric System-decimal system of measurement, units are based on multiples of 10.

METRIC UNIT

TOOL USED

Length Meter, Centimeter, Kilometer

Ruler,Meter stick

Volume Liter, Milliliter

Graduated Cylinder

Mass Kilogram, Gram

Balance, Scale

Temperature – water boils at 1000C; water freezes at 00C

Metric system has been revised to Internationals System of Measurement (SI)

A Common Measurement System

Microscopes

Allow light to pass through the specimen and use two lenses to form an image

Live specimens may be viewed

Dyes may be used to view better images

Compound Light Microscope

Electron microscopes

Use a beam of ELECTRONS to produce images

Specimens must be dead; preserved and dehydrated

Transmission electron microscopes (TEMs) detail within the cell

Scanning electron microscopes (SEMs)

three dimensional images of the surface

Laboratory Techniques

Cell Cultures – group of cells grown in a nutrient rich solution from a single original cell

Cell Fractionation – separate the different cell parts

Cells are broken in a special blender

Cell bits are added to liquid and placed in a tube

Tube is placed in a centrifuge (spins the tube)

Cell parts separate with most dense parts settling near bottom

Working Safely in Biology

Read the steps and understand the procedure

Always follow the teacher’s and textbooks instructions exactly

Wash your hands after each activity.

You are responsible for your own safety and that of your teacher and classmates!