Phase (different interference) contrast microscopy, Biology

Phase (different interference) Contrast microscopy:

Living cells are mostly   transparent. For viewing under ordinary light microscope, therefore, live cells must be stained with vital stains, or these must be fixed and then stained with acid or basic dyes. Zernicke (1940) designed a phase contrast microscope for viewing unstained living cells. This microscope has the same resolving power as the ordinary light microscope. but takes advantage  of the fact that light rays pass through  various cells parts at different velocities due to varying thickness and densities  of  the parts. In other words, various cell parts have different refractive indices i.e. they refract or bend the light rays to different extents. Obviously, light waves emerging from different cells parts are out of phase with each other. A phase contrast microscope converts these differences in phase to differences in light intensity, producing an image with good contrast, much of what we know about cell division, cell under phase contrast microscopes.

Merton (1947) Ambrose, Dyson, Smith and others have contributed in designing interference microscopes based on principles similar to those of phase contrast microscopes, but with an added advantage of giving quantitative data of the measurement of dry weight of various cell parts.

Posted Date: 9/26/2012 7:09:26 AM | Location : United States







Related Discussions:- Phase (different interference) contrast microscopy, Assignment Help, Ask Question on Phase (different interference) contrast microscopy, Get Answer, Expert's Help, Phase (different interference) contrast microscopy Discussions

Write discussion on Phase (different interference) contrast microscopy
Your posts are moderated
Related Questions
Q. Spontaneous deamination of cytosine: 1. Deamination of cytosine is common and results in conversion of cytosine to uracil 2. can be repaired by excision repair process (i)


Radial artery: Carpentier used radial aartc14y us a conduit for CABG in 197 1. He had 30 percent early occlusion of the graft and it was given up. The mail1 problem was radi

How will you evaluate periimplant marginal tissues? Evaluation of the perimplant Marginal tissues can be done by using following parameters: i) Assessing the marginal mucos

The hydrolysis of the disaccharide lactose (in milk) give up glucose and galactose. Thus galactose is also a major dietary sugar for humans. Glucose and Galactose are epimers which

Explain Differential Staining Technique? It divides bacteria into separate groups based on staining properties, like Gram's stain, Acid-fast stain etc. Here 2 or more contrasti

What is Prokaryotic Gene Expression ? Control of prokaryotic gene expression occurs primarily at the level of transcription. Prokaryotic genes are arranged in units consisting

Q. What are changes in ST-Segment? Normal Exercise Electrocardiogram ST and J Point As the heart rate increases with exercise, a number of predictable changes occur in a

Explain Tocopherols These are the most widely distributed antioxidants in nature, and they constitute the principal antioxidants in vegetable oils.  A relatively high proportio

Development of Heart in Amphibians The heart and the surrounding pericardial cavity build up from lateral mesoderm. After gastrulation, the mesodermal mantles carry on to gro