Light microscope vs. Electron microscope

Reporting in cell and molecular biology for prelim period.

1. Light vs. Electron microscope Presented by: Group 1: Remiel Alquileta Jamica Ambion Celline Ancheta HUB 42

2. History the 1590's, two Dutch spectacle makers, Zacharias Jansen and his father Hans started experimenting with these lenses

3. History Anton van Leeuwenhoek  a Dutch draper and scientist, and one of the pioneers of microscopy who in the late 17th century became the first man to make and use a real microscope .

4. History Hooke's Micrographia ,   is Robert Hooke’s most famous work and is notable for the stunning illustrations, drawn by himself .

5. History Modern compound microscopes With the advancement of technology and improved optics, the microscope as we know it today came into being.

6. Uses of Microscope Cytology Pharmacoloy Microbiology Histology

7. RESOLVING POWER Ability of a microscope to differentiate between two close together objects. Higher resolution means that objects are closer together and can be seen as separate points.

8. Light Microscope The term  light  refers to the method by which light transmits the image to your eye.  Microscope  is the combination of two words; "micro" meaning small and "scope" meaning view. Optical microscopes are the oldest design of microscope Using a  light microscope , one  can  view cell walls, vacuoles, cytoplasm, chloroplasts, nucleus and cell membrane.  Light microscopes  use lenses and  light to magnify cell parts. 

9. Types of Light Microscope A   simple microscope  is a microscope that uses a lens or set of lenses to enlarge an object through angular magnification alone, giving the viewer an erect enlarged  virtual image. Simple light microscopes of the past could magnify an object to 266X

10. Types of light microscope Dissecting microscope - magnification: 10-40x - not use for cellular level - specimens can be living or non-living.

11. Sample image from dissecting microscope

12. Types of Light microscope A  compound microscope  is a microscope which uses a lens close to the object being viewed to collect light (called the objective lens) which focuses a real image of the object inside the microscope Modern compound light microscopes, under optimal conditions, can magnify an object from 1000X to 2000X

13. Sample images from light microscope

14. Advantages Limitation Easy to use Cheap True color but sometimes require staining Could use live specimens Low resolution due to shorter wavelength of light (0.2nm) Low magnification (max. 1250x) Specimen used is thin

15. Electron Microscope An  electron microscope  is a microscope that uses a beam of accelerated  electrons  as a source of illumination A transmission electron microscope can achieve better than 50  pm resolution and   magnifications  of up to about 10,000,000x   Y ou need to use particles that are smaller than photons to start with: in other words, you need to use  electrons In an electron microscope, a stream of electrons takes the place of a beam of light and allows us to see things smaller even than light itself.

16. Scanning Electron microscope A Scanning electron microscopes are designed to make images of the surfaces  of tiny objects. Advantages: - High resolution (1nm) - Provide detailed images of surface structures. - High magnification (200,000x) - 3D images

17. SEM Limitations : - expensive - requires extensive training - sample must be dead (vacuum, stained) - black and white/false colour image

18. Transmission Electron Microscope T ransmission electron microscopes are the most powerful electron microscopes: we can use them to see things just 1  nanometer  in size, so they effectively magnify by a million times or more . A  transmission electron microscope  fires a beam of electrons  through  a specimen to produce a magnified image of an object .

19. Advantages Disadvantages Higher resolution (1nm) Provides detailed images of interior structures Higher magnification (500,000x) Expensive Extensive training required Samples must be dead (vacuum, stained) Black and white/ False colour images

20. Summary

21. Refences Comparing microscopes: https:// www.youtube.com/watch?v=b4WOsYktdn4 Microscopes - SC.912.L.14.4 https :// www.youtube.com/watch?v=6vZZeWqbmU8 http:// www.cas.miamioh.edu/mbiws/microscopes/compoundscope.html#how it works http://www.history-of-the-microscope.org/history-of-the-microscope-who-invented-the-microscope.php

22. Laboratory Reagent and Preparations Calculation Calculate the grams of each substance required to prepare the following solutions: a. 50 mL of 0.4 M sucrose b. 100 mL of 0.5 M H2SO4

23. Solutions! A) 50 mL of 0.4 M sucrose M = moles= 0.4M = (0.4M)(342 ) = 136.8 g   B) 100 mL of 0.5 M H2SO4 M = moles= 0.5M = (0.5M)(98 ) = 49 g