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

Structure and content of neuropsychological battery, Structure and Content ...

Structure and Content of NEUROPSYCHOLOGICAL BATTERY The battery contains 269 items, each of which may be scored on a 2- or 3- point scale. A score of 0 indicates normal perform

Properties of pyridoxine, Properties of pyridoxine a)  It forms white, ...

Properties of pyridoxine a)  It forms white, odourless  crystals. b)  The compound is readily soluble  in water. c)  When  a neutral or alkaline solution of pyridoxine is

Radiographic imaging, R a d i o g raphic imaging: ...

R a d i o g raphic imaging: Radiology has been in use since the discovery of X-rays by Wilhelm Conrad Roentgen in 1895. Until 1980s, radiography was the

Verify that the transforming agent in a bacteriophage, Which of the followi...

Which of the following experimental steps permitted Hershey and Chase to verify that the transforming agent in a bacteriophage is DNA as well? A. Phage particles were mixed wit

Pelagic zone - organisation of the marine ecosystem, Pelagic Zone - Organis...

Pelagic Zone - Organisation of the Marine Ecosystem The waters contained in the sea basin, constitute the pelagic zone which is divided into The neritic zone situ

Plant, what is the scientific explanation of "touch me not" plant that can ...

what is the scientific explanation of "touch me not" plant that can react due to any touch

Explain use of repellents, Use of repellents Avoidance and early remova...

Use of repellents Avoidance and early removal of ticks are the first steps in prevention of Lyme disease. In highly endemic areas, when an engorged Ixodes scapularis tick is at

Explain about the radiation therapy, Explain about the Radiation Therapy? ...

Explain about the Radiation Therapy? Radiation therapy is one of the options for the treatment of various tumors. During the administration of radiation patients experience acu

Indications for surgery- pulmonary stenosis, Indications for Surgery :  Co...

Indications for Surgery :  Congenital pulmonic stenosis is the most common lesion requiring relief. Very rarely it could be due to rheumatic involvement along with disease of othe

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