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

Explain the manifestations of iron deficiency anaemia, Explain the Manifest...

Explain the Manifestations of Iron Deficiency Anaemia? • Paleness of conjunctiva • Paleness of tongue • Paleness of mucosa of soft palate • Low haemoglobin • Swelling of

Determine the amount of vasopressin, Consider the case of a rare mutant in ...

Consider the case of a rare mutant in which the concentration of solutes in the kidney medulla interstitial spaces is equal to the concentration of solutes in the liquid in the lum

Iodine - mineral elements, IODINE The element is available is drinking ...

IODINE The element is available is drinking water, vegetables and fish. Table salts are also compulsorily iodized to provide iodine in the diet. All sea foods are rich in

What is a distilling flask and how is it used, What is a distilling flask a...

What is a distilling flask and how is it used? A distilling flask is a round bottom flask that often has two openings, and some of them have a long neck.

Explain the membrane equilibria, Explain the Membrane Equilibria? A sem...

Explain the Membrane Equilibria? A semipermeable membrane used to separate two liquid phases can, in principle, be permeable to certain species and impermeable to others. A mem

Indications of phototherapy, Indications i) When there is an abnormal...

Indications i) When there is an abnormal rise in the bilirubin level which may be due to physiological or pathological jaundice or any other problem. ii) Prophylactic ph

Pre and post-operative nursing care of a child, Pre-operative and Post-oper...

Pre-operative and Post-operative Nursing Care of a Child with Cleft Lip: We shall begin with pre-operative nursing care and then focus on post-operative care. As you know that

Explain the urinary excretion of ascorbic acid, Explain the Urinary excreti...

Explain the Urinary excretion of Ascorbic Acid? The urinary excretion of ascorbic acid falls when the dietary intake is low. Since the tissues are not saturated, a greater part

Infructescences- pseudofruits and parthenocarpic fruits, What are the infru...

What are the infructescences, pseudofruits and parthenocarpic fruits? The Infructescences are aggregated fruits formed from inflorescences, aggregated flowers. Grape clusters a

Define about the nutritional deficiencies, Define about the nutritional def...

Define about the nutritional deficiencies? The nutritional deficiencies which have been identified in the group of elderly are of total calories, protein, vitamin A, vitamin C,

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