Download presentation
Presentation is loading. Please wait.
Published byBrendan Gray Modified over 8 years ago
1
Microscopy Microscopes are tools that extend human vision by enlarging images of objects. Biologists use microscopes to study cells, cell parts, diseases and molecules. Resolution is the power to show details clearly in an image. Microbiology- the study of microorganisms
2
Early Microscopes - Anton Van Leeuwenhoek The father of microscopy, Anton Van Leeuwenhoek of Holland (1632-1723). Anton Van Leeuwenhoek was the first to see and describe bacteria (1674), yeast plants, the teeming life in a drop of water, and the circulation of blood corpuscles in capillaries.
5
Robert Hooke In 1665, the English physicist Robert Hooke looked at a sliver of cork through a microscope lens and noticed some "pores" or "cells" in it. Hooke was the first person to use the word "cell" to identify microscopic structures when he was describing cork.
6
Antique microscopesAntique microscopes (link)
7
Light Microscopes Compound light microscope shines light through a specimen to be viewed on a glass slide. The specimen has to be thing enough for light to pass through it. Typical magnification ranges from 40x to 400x –Can go up to 2000x
8
Parts of the Microscope
9
Arm Supports the body tube. Used to carry the microscope. Base Bottom part of the microscope often shaped like a horseshoe. Arm and Base
10
Stage Place where the object you are looking at (Specimen) is placed Stage Clips Holds down the slide on the stage. Stage and Stage Clips
11
Eyepiece Magnifies the image by 10x Body Tube The hollow tube through which light passes. It holds the lenses apart. Eyepiece (Ocular Lens) and Body Tube
12
Course Focus Raises or lowers the Body Tube to focus. Only used under low objectives Fine Focus Raises and lowers the Body Tube and used to bring objects into focus. Course and Fine Focus
13
The NOSEPIECE is the round part that holds the OBJECTIVE LENSES apart. Nosepiece
14
Diaphragm Changes the amount of light reaching the objective lenses. Located under the Stage. Light Source Located beneath the Stage and Diaphragm. Sends light towards the hole in the stage. Diaphragm and Light Source
15
Objective Lenses Objective lenses increase from low power to higher power Generally 4X, 10X, 40X To find total magnification, multiply eyepiece (10x) by objective power Ex. 10x by 4x = 40 x total magnification
16
Electron Microscopes Used t0 examine cells in more detail or to view viruses Uses a beam of electrons to produce an enlarged image of the specimen Greater magnification and resolution than light microscopes Electron microscopes cannot be used to view live specimens
17
Scanning Electron Microscopes (SEM) SEM passes a beam of electrons over the specimens surface SEMS provide a 3 dimensional image of the specimen The specimen has to be sprayed with a fine metal coating, the beam of electrons causes the metal coating to emit a shower of electrons that project onto a fluorescent screen SEMS magnify objects up to 100,000 times
19
Transmission Electron Microscope (TEM) TEM transmits a beam of electrons through a very thinly sliced specimen Magnetic lenses enlarge the image and focus it on a screen TEMs can magnify objects up to 200,000 times
20
1.Body Tube 2.Nose Piece 3.4X magnification 4.10x magnification 5.40X magnification 6.Stage Clips 7.Diaphragm 8. Light Source 9.Eyepiece 10.Arm 11.Stage 12.Course Adjustment 13.Fine Adjustment 14.Base
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.