Tools of a Biologist

Microscopes: number one tool of a biologist Small -to view Function: microscope are instruments used to view very small objects. In biology we will use it to view…. living cells and unicellular organisms.

Compound Light Microscope Eyepiece/Ocular lens X10 Nose tube Arm Revolving nose piece Objective lenses Stage Low: shortest/red/x4 Medium: med/yellow/x10 High: longest/blue/x40 Course Adjustment knob Stage clips Diaphragm Fine Adjustment knob Light Base

There are 3 types of microscopes used in biology: 1. Compound light microscope -Compound- look through 2 lenses at the same time in order to properly magnify the organism.

Total magnification: low power: ocular lens x10 low objective x4 -------------- x40 medium power: med objective x10 x100 high power: high objective x40 x400

Compound light microscope: -light must pass through the diaphragm and through the object. -object must be “thin” or transparent so the light can pass through it. -Diaphragm: regulates the amount of light that can pass through. -Best setting of the diaphragm is #2

Staining The purpose is to: add color to a cell so that the cell and its structures can be seen more clearly through a microscope.

Limit of Resolution -is the point at which you see an item most clearly. Any magnification above or below that point will results in the object looking blurry.

Type 2: Stereoscope -Used to view the surface of objects which are too large for light to pass through them. -Uses 2 lights to illuminate the surface of the object. -Stereo means “3 dimensional” -Provides a 3-D detailed look at the surface of an object.

-look through 2 ocular lenses -magnifies between x10 to x60

Type 3: Electron Microscopes Uses electrons to form an image and NOT light Has a very high limit of resolution. -can see items very clearly at any magnification -can magnify up to 500,000x and still be clear Object is placed in a vacuum No air No oxygen Organism is DEAD

Two types of electron microscopes: 1. T.E.M. ~ Transmission Electron Microscope Produces a 2-D, black and white image of inside of a cell.

2. S.E.M. ~ Scanning Electron Microscope Produces a 3-D, black and white image of the surface of an object.

Review of the tools biologist use: Microscope used to: -view very small living things like cells   Staining used to: -add color to transparent objects so we can see them better Graphing used to: -analyze data collected in a picture form

Additional tool of a biologist: Chrom means= Graph means= -color -picture There for chromatography means: a “color picture” Tool used to separate the components of a mixture by their different densities. Chromatography:

It is used by scientist to: To separate the different substances that make up a mixture What is a mixture? -two or more substances combined together but each substance retains its own properties

What is the job of chloroplast?

Get separated by the substances different densities therefore the travel different distances.

Least dense-traveled the furthest up the paper MOST. dense- traveled the least distance up the paper

Did he change his 3’s into 8’s? DID PETE CHEAT??? Did he change his 3’s into 8’s?