Tools of a Biologist. Microscopes. Micro=Scope= Small-to view. A microscope is an instrument used to view very small objects. In biology it is used to view living…. cells and unicellular organisms. Compound Light Microscope. Eyepiece / Ocular lens X10. Nose . Arm. - PowerPoint PPT Presentation
Tools of a Biologist
Tools of a Biologist
A microscope is an instrument used to view very small objects.
In biology it is used to view living.cells and unicellular organisms.Compound Light Microscope
Eyepiece / Ocular lensX10Nose ArmCourse Adjustment knob:
Moves stage up and downStage and Stage clipsFine adjustment knob:
Fine focuses the image for your eyes Revolving lenses
Low power objective lens. Shortest lensRed in colorX4Medium power objective lensMedium in lengthYellow in colorX 10High power objectiveLongest in lengthBlue in colorx40
Light sourceBaseDiaphragm: regulates the amount of light that passes through the stage
There are 3 types of microscopes are used in biology:
1. Compound light microscope-Compound-look through 2 lenses at the same time in order to properly magnify the organism.
low power:ocular lens x10low objective x4-------------- x40medium power:ocular lens x10 med objective x10-------------- x100high power:ocular lens x10 high objective x40-------------- x400
Compound light microscope:
-light -light must pass through the diaphragm and through the object.
-object must be thin or transparent so the light can pass through it.
Is a method of adding color to a cell so that the cell and its structures can be seen more clearly through a microscope.Limit of Resolution
The 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 to 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 through2 ocular lenses -magnifies between x10 to x60
Type 3: Electron Microscopes Uses electrons to form an image and NOT lightHas a very high limit of resolution.-can see items very clearly at any magnification-can magnify up to 500,000x and still be clearObject is placed in a vacuumNo airNo oxygenOrganism is DEADProduces a 2-D, black and white image of inside of a cell.Two types of electron microscopes:1. T.E.M. ~ Transmission Electron Microscope
2. S.E.M. ~ Scanning Electron Microscope
Produces a 3-D, black and white image of the surface of an object.Additional tools of a biologist:Chromatography:
Tool used to separate the components of a mixture by their different densities.