Tools In Studying Microbiology Flashcards
The five “I”s of Microbiology
-Inoculation
-Incubation
-Isolation
-Inseption
-Identification
Introduction of a sample into a sterile culture media
Inoculation
allowing cultures to grow under favorable growth conditions using an incubator
Incubation
separating one bacterial species to another using streak
plating or pour plating techniques
Isolation
observation of different characteristics by naked eye
(macroscopic) or under a microscope (microscopic)
Inspection
identifying the genus and species of the sample using
biochemical tests, DNA-based methods, immunological testing
Identification
instrument used to visualize micrometers or
micron (μm) size objects such as microorganisms and cells,made up of lenses for magnification
The Microscope
Ability to enlarge objects
Magnification
Ability to show details
Resolving power
power objective x power of ocular lens
Total magnification
Magnification in most microscopes results from interaction
between visible light waves and curvature of the lens.
..
angle of light passing through convex surface of glass changes
Refraction
requires the use of oil to prevent refractive loss of light
Oil immersion lens
Types of microscope
Light and Electron microsope
uses visible light, 400-750 nanometers (nm), magnification between 40-2000x
Light microscope
uses electron beams, electron waves are 100,000 times shorter than the waves of visible light, magnification is between 5,000- 1,000,000x
Electron Microscope
Parts of microscope
1.Eyepiece
2.Objective Lens
3.Nose Piece
4. Adjustment knobs
5. Stage
6. Aperture
7. Microscopic illuminator
8. Condenser
9. Diaphragm
10. Condenser focus knob
11. Stage control
-also known as the “ocular”
- a part used to look through microscope
- standard magnification is. 10x with an optical eyepiece from 5x to 30x
Eyepiece
-These are the major lenses used for specimen visualization. They have a magnification power of 40x-100X. There are about 1- 4 objective lenses placed on one microscope, each lens has its own magnification power.
Objective lens
- Also known as the revolving turret. It holds the objective lenses. It is movable hence it can revolve the objective lenses depending on the magnification power of the lens.
Nose piece
-These knobs that are used to focus the microscope. There are two types of adjustment knobs i.e fine adjustment knobs and coarse adjustment knobs.
Adjustment knobs
-This is the section in which the specimen is placed for viewing. They have stage clips that hold the specimen slides in place. The most common stage is the mechanical stage, which allows the control of the slides by moving the slides using the mechanical knobs on the stage instead of moving them manually.
Stage
-This is a hole on the microscope stage,through which the transmitted light from the source reaches the stage.
Aperture
-This is the microscope’s light source, located at the base. It is used instead of a mirror. It captures light from an external source of a low voltage of about 100v.
Microscopic illuminator