Radioactive labelling, Biology

Assignment Help:

Radioactive Labelling

Radioactive labelling method has been effectively applied on the chick blastoderm. The method includes labelling one embryo (donor) and grafting a part of it in similar position on another unlabelled embryo of similar stage (Host). An explanted blastodermis immersed in a medium consisting of the radioactive mtiated (H3) thymidine. In 3 to eight hours the tritiated thymidine is incorporated into the chromosomal DNA of dividing blastodermal cells. The embryo labelled in such type of a way by tritiated thymidine serves as a donor. Another embryo at similar stage of development as attained through the labelled donor in the meantime is then chosen to serve as the host. A small area of the host embryo is excised and replaced by a corresponding piece from the donor of which the fate is to be determined. Healing generally takes place quickly and the development is not impaired if the operation has been done carefully.

The thymidine does not pass out of the nuclei of the labelled cells but stays in the chromosomes of their descendents. Even though the radioactive thymidine present in the DNA is gradually diluted with each subsequent chromosomal replication radioactivity remains for a considerable time. Such type of composite embryo (partly from donor and partly from the host) is tested at a later stage of development for radioactivity through special techniques like autoradiography etc. Only the part(s) or structure(s) developed from the grafted piece display the presence of radioactivity thus establishing the fate of specific area taken from the donor.


Related Discussions:- Radioactive labelling

Male reproductive disorders-blockage of ducts, Blockage of ducts In so...

Blockage of ducts In some bulls there is a blockage of the transport of sperm through the epidydimis usually caused by a congenital non-patency of some part of the vasa effere

Life processes, mode of nutrition : out side the body

mode of nutrition : out side the body

Lead strength, When the R-wave in the lateral precordial leads is less than...

When the R-wave in the lateral precordial leads is less than 10 mm the sensitivity of ST depression is very low if 1 mm of ST depression is used as a standard. The corrected ST for

Systematics, binomial nomenclature is not applicable to

binomial nomenclature is not applicable to

Descriibe mechanical ventilation and cardiac performance, Descriibe Mechani...

Descriibe Mechanical Ventilation and Cardiac Performance During spontaneous breathing, the intrathoracic and intrapulmonary pressures are negative, while with mechanical venti

Procedure for define percentage of reducing and total sugar, Procedure For ...

Procedure For Define Percentage of reducing and total sugar by fehling soxhlet? 1. Standard titration (Standardization of Fehling's solution) - Titrate 10 ml of Fehling's solut

What proportion of children with down syndrome, What proportion of children...

What proportion of children with down syndrome do you expect when women with down syndrome have children with men who have 46 chromosomes? justify answer

Technique-ross operation--surgical techniques, Technique : The suitability...

Technique : The suitability of the pulmonary autograft for aortic valve replacement has to be studied by accurate measurement by echocardiogram of the aortic and pulmonary annuli.

Erythrocytes or red blood cells, Erythrocytes or red blood cells: Th...

Erythrocytes or red blood cells: These are otherwise called Red Blood cells or corpuscles. These are the most numerous cells in the blood.There are about 4.5 to 5.5x 10 9

What is meant by substrates of enzymatic reactions, What is meant by substr...

What is meant by substrates of enzymatic reactions? Substrates are reagent molecules upon which enzymes act. The enzyme has spatial binding sites for the attachment of its s

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