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

Epidemiological association between hemophilia and hiv, Q. What is the epid...

Q. What is the epidemiological association between hemophilia and HIV infection? In the past the blood banks did not usually perform HIV detection tests and many hemophilic pat

Define energy requirements of infants, Define Energy requirements of infant...

Define Energy requirements of infants? Energy: Energy requirements of infants are based on the energy intake through breast milk by infants of well-nourished mothers. Based on

Ribosome in the translation of one mrna molecule, Q. How many of the same p...

Q. How many of the same proteins are made at the same time by each ribosome in the translation of one mRNA molecule? How does successive protein production occur in translation?

What are the three main types of trophic pyramids, What are the three main ...

What are the three main types of trophic pyramids studied in Ecology? The three types of trophic pyramids studied in Ecology are the numeric pyramid, the biomass pyramid and th

Show major treatments of diabetes mellitus, Q. What are the major treatment...

Q. What are the major treatments of diabetes mellitus? The general goal of the diabetes curing is to keep normal glycemic levels. Type I diabetes is treated with parenteral

Considerations for congestive cardiac failure, Q. Considerations for conges...

Q. Considerations for congestive cardiac failure? - Subjects with congestive cardiac failure often tolerate small frequent meals better than larger infrequent meals as these a

Conductometry, conductometry and its uses in biological experiments

conductometry and its uses in biological experiments

Respiration, what are the organs of respiration in lower forms of animals?

what are the organs of respiration in lower forms of animals?

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