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

What is muscular dystrophy, What is Muscular dystrophy Muscular dystro...

What is Muscular dystrophy Muscular dystrophy :- Defects in the muscle due to faulty nutrition.

Explain the term mutations, Explain the term Mutations? Mutations are c...

Explain the term Mutations? Mutations are changes in the genetic structure of an organism that occur at random or are the results of environmental causes. The majority of new m

The two regulation systems of glycogen metabolism, Mention the two regulati...

Mention the two regulation systems of glycogen metabolism. There is a hormonal regulation system functioning  in the muscle and liver which regulates  the glycogen metabolism.

Left atrio-ventricular, The left atrio-ventricular aperture in man is guard...

The left atrio-ventricular aperture in man is guarded by

Competition - processes in succession , Competition - Processes in Successi...

Competition - Processes in Succession The aggregation of individuals in an area leads to inter specific and intra specific competition. The competition is usually for

What is the heterotrophic hypothesis on the origin of life, What is the het...

What is the heterotrophic hypothesis on the origin of life? As per to the heterotrophic hypothesis the first living beings were very simple heterotrophic organisms that is not

Conditions necessary for outbreak of botulism, Q. Conditions Necessary for ...

Q. Conditions Necessary for outbreak of botulism? The following conditions are necessary for an outbreak of botulism: 1. Presence of spores of C. botulinum of type A, B o

Explain the pair of chromosomes and sex chromosomes, Explain the pair of c...

Explain the pair of chromosomes and Sex Chromosomes? Morgan also noticed that one pair of chromosomes is different in male and female flies, one of the male chromosomes being

Qualitative and quantitative analysis of colour, Q. Qualitative and Quantit...

Q. Qualitative and Quantitative Analysis of Colour? Primarily, two types of analysis are carried out for food colours - qualitative and quantitative. The qualitative analysi

Buffalo-pox, B u f fa l o- p o x The disease i...

B u f fa l o- p o x The disease is caused by an orthopox virus, closely related to the vaccinia virus. It is not clear whether it should be considered

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