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

Changes in chromosome number, Aneuploidy : One or inore chron~osomes of a n...

Aneuploidy : One or inore chron~osomes of a normal set nlay bc lacking or present in excess. The term riullison~y refers to absence of both the chromosomes of a pair. Monosomy, tri

Explain genetically modified foods, Normal 0 false false fa...

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

Can you explain irradiation, Q. Can you explain Irradiation? Irradiati...

Q. Can you explain Irradiation? Irradiation: It is the process of exposing food to carefully controlled amount of ionising energy to destroy and control microorga

Ascitic fluid collection - specimen collection, Pleural, Pericardial, and A...

Pleural, Pericardial, and Ascitic fluid Collection:      The procedure is called paracentesis . If for pleural cavity is called thoracocentesis , and for pericardial cavity c

Explain digestion and of digestive system of platyhelminthes, Q What are th...

Q What are the kinds of digestion and of digestive system of platyhelminthes? Flatworms have incomplete digestive systems and they present intracellular and extracellular compl

Phylum annilida, how we attempt a question of phylum annilida in exam?

how we attempt a question of phylum annilida in exam?

What is the phenotype, What is the phenotype? Phenotype is every observ...

What is the phenotype? Phenotype is every observable characteristic of a living being conditioned by its genes. A few phenotypes may be altered by nongenetic factors (for insta

Why use the properties of water, In agriculture areas, farmer pay close att...

In agriculture areas, farmer pay close attention to d weather forecast. Right before a predicted overnight freeze, farmers spray water on crops to protect the plants. Use the prope

filtration, It is the process of separating colloidal and suspended impuri...

It is the process of separating colloidal and suspended impurities from water by passing it through a porous bed made of fine sand and other proper sized granular materials. Filtra

Why pregnancy and lactation are critical stages in lifecycle, Why Pregnancy...

Why Pregnancy and lactation are critical stages in lifecycle? You must be aware that the situation of women is far from optimal and it is necessary to give attention to their n

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