Autoradiography, Biology

Assignment Help:

Autoradiography

Autoradiography is a modification of the radioactive tracer technique. In this technique, the radioactivity is detected by a thin film of photographic emulsion containing silver compounds which is put over a labelled cell or tissue. The rays emitted by radioisotope from the cell or tissue expose the photographic emulsion like a photographic film which is developed in a dark room. Silver grains are seen as black dots on parts of the specimen where radioisotope is accumulated.

Autoradiography reveals the metabolic processes of the cell. For example, by labelling cells with 3H thymidine, it is found that silver grains are localised in nucleus, which shows that DNA is synthesised in the nucleus. Similarly, by labelling cells with 3H uridine, silver grains are first seen in nucleus and then after some time these grains appear in the cytoplasm. This clearly demonstrates that RNA is initially synthesised in the nucleus but later on migrates to the cytoplasm.

Different radioisotopes are used for localising different macromolecules. As stated earlier,  cells are labelled with 3H thymidine for the studX of DNA metabolism, 3H uridine to study RNA metabolism, tritiated amino acids for examining the synthesis of proteins, treated monosaccharides such as 3H-mannose and 3H-fucose for examining the synthesis of polysaccharides.


Related Discussions:- Autoradiography

Microbiology, harmful and benificial microbes

harmful and benificial microbes

Trace minerals-chromium, Chromium Chromium functions as a component of ...

Chromium Chromium functions as a component of the glucose tolerance factor, which serves to potentiate the action of insulin. Adding low concentrations (0.02 to 1.0 mg/kg) of c

Explain the term blood, Explain the term Blood Blood is a fluid and con...

Explain the term Blood Blood is a fluid and consists of plasma and blood cells. More than 90 percent of plasma is water. Other constituents of plasma are plasma proteins i.e. a

Effects of flow limiting stenosis on blood flow, 1) The presence of epicar...

1) The presence of epicardial coronary artery stenosis caused by artherosclerotic plaques is by far the most frequent angiographic finding in any cardiac ischaemic syndrome. 2)

What is pus, What is pus Pus is a residual of the inflammatory reaction...

What is pus Pus is a residual of the inflammatory reaction. It is having a mixture of fragments of dead leukocytes, infectious agents (generally bacteria) and tissues.

Explain reversion flavor, Reversion flavor:  The rapid oxidation of br...

Reversion flavor:  The rapid oxidation of branched furan fatty acids on exposure to light, leads to the production of an intensive aromatic substance, which along with diacety

Uricotelic excretion essential for avian and reptile embryos, Why is the ur...

Why is the uricotelic excretion essential for avian and reptile embryos? In reptiles and birds the excretory system is uricotelic as uric acid is insoluble, less toxic and sui

Define the phosphorus - the macromineral, Define the Phosphorus - The Macro...

Define the Phosphorus - The Macromineral? The body contains about 620 g (20 moles) of phosphorus. Of this 87% is present in bones. It is thus more widely distributed in the bod

Exchange transfusion, Exchange transfusion An exchange transfusion is ...

Exchange transfusion An exchange transfusion is the serial withdrawal and injection of small amounts of blood through a central vein-usually umbilical until the required volu

Explain the most probable number (mpn), Explain the Most Probable Number (M...

Explain the Most Probable Number (MPN)? MPN is a statistical estimating technique which is based on the fact that more the number of bacteria in a sample, more is the dilution

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd