Chapter 2 MICROSCOPY Flashcards
are tools used to enlarge images of small objects
process of using microscope in investigating or studying microorganism
Microscope
Microscopy
very first magnifiers, 1000 BC, using blow glasa globes with ___ to magnify things
Water
___ are made of curved, ckear pieces of glass or plastic called lenses
All light rays lassing through the lens bend toward a point called the ___
Magnifiers
Focus
1590, ____ and _____ ____ from Holland have developed the compound microscope. They were just ordinary lens makers.
Johannes and Zacharias Janssen
1624, Italian astronomer Galileo Galilei develop the
microscope and telescope
1656, German mathematician Kircher made a microscope in which he saw “small worms” when he studies ___
Plaque
1661, Italian physician ____ was the first to use microscope in his anatomical studies. Showed trachea (windpipe) leads to two bronchi.
Marcelo Malphigi
1674, Dutch merchant and microscopist Anton van Leeuwenhoek devised microscope with a magnification of 200-300x. Observed moving organisms, animalcules. He was considered to open door to
“invisible world of microorganisms.
Majority of microscope are called _____
Light (bright field) microscopes
- Also referred to as a biological or research microscope
- Refer to as a high power microscope
- Mag. 40x-1000x, some up to 1500x or 2000x
- Image seen as if 10” (250mm) from observer
- 2-D, reversed and upside down
- light method is trans-illumination (light projectes from below)
Compound microscope
- found at top where you look through
- us. 10x, 12x, 15x mag. power
Eyepiece
Connects eyepiece lens to the objective lens
Tube
Supports the tube and connects it to the base. It is used along with the base in carrying microscope.
Arm
The bottom of the microacope. Used to support the entire microscope
Base
A steady light source used in place a mirror
Illuminator
A flat platform where you place the slide.
Holds the slide in place, used along with this.
Stage
Stage clips
The parts that holds two or more objectives. It can be rotate to change the magnification easily.
Revolving nosepiece/ Turret
Almost always consist of 4x, 10x, 40x and 100x powers
Short lens - lowest power
Longest lens - greatest power
Objective lenses
An adjustment fhat determines how close the objwctive lens can get to the slide
Rack stop
Is used to vary the intensity and size of the cone of light that is projected upward into the slide
Diaphragm
Focus the microscope, used only with LPO
Coarse adjustment knob
Focus the microscope, used with HPO to bring the specimen into better focus
Fine adjustment knob
- Also referred to as dissecting, dissection, or inspection microscopes
- Refer to as a low-power microscope
- 3D, upright and normal image
Stereo microscope
- uses a beam of accelerated electrons as a source of illumination
- having a high resolution of images
- magnify objects in nanometres
- Ernst Ruska
Electron Microscope
- used to view thin specimens through which electrons can pass generating a projection image
- analogous to compound (light) microscope
- to image the interior of cells, structure of protein molecules, the organization of molecules in viruses and cytoskeletal filaments, and the arrangement of protein molecules in cell membranes
Transmission Electron Microscope (TEM)
- analog to stereo light microscope
- provides detailed images of the surfaces of cells and whole organisms
- used for particle counting and size determination, and for process control.
- because the image is formed by scanning a focused electron beam onto the surface of the specimen in a raster pattern
Scanning Electron Microscope (SEM)
uses the differences in the phase of light
transmitted or reflected by a specimen to form distinct, contrasting images of different
parts of the specimen.
Phase Contrast
- uses a laser light to scan samples that have been dyed
- with the aid of a dichromatic mirror
- can create 3-D images; by assembling multiple scans
- commonly used in cell biology and medical
applications
Confocal Microscope
the object viewed is illuminated by polarized light
for typically analyzing the content and make-up of organic or inorganic material like crystals, chemical microscopy, and optical mineralogy
Polarizing
used for identification, inspection, and analysis
of different metals and alloys
Metallurgical
- combination of a microscope and a digital camera
- can use a CCD or CMOS chip
- user can display, save, and edit images
Digital
use new technology for a miniature camera and illuminator in one unit
Handheld Digital Microscopes
how magnification is determined?
by multiplying the power of the eyepiece by the power of the objective lens being used
- the diameter of the circle of light that you see when looking into a microscope
- is measured in millimeters
- the lowest powers have the ____
- increase power, have the _____
field of view
widest field of view
smallest field of view
