Radioactive labelling, Biology

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.

Posted Date: 1/25/2013 4:41:35 AM | Location : United States







Related Discussions:- Radioactive labelling, Assignment Help, Ask Question on Radioactive labelling, Get Answer, Expert's Help, Radioactive labelling Discussions

Write discussion on Radioactive labelling
Your posts are moderated
Related Questions
Define Protein requirements of infants? Protein allowances of infants should meet both growth and maintenance requirements. Protein allowances are computed from the protein con

Explain Turnover number Turnover number:- The  number  of  molecules  of substrate  transformed per catalytic  site of the enzyme per minute,

Q Lower Oesophageal Sphincter? Competency of LES (Lower Oesophageal Sphincter) is important. The pressure of this sphincter is controlled by many factors, one of which is hormo

Abortions Abortion in dairy cattle is commonly defined as a loss of the foetus between the age of 42 days and approximately 260 days (buffaloes 300 days). It is important to d

main external morphological feature that differentiates platyhelminthes from nematodes

(i) Name one fibrous and one globular protein. fibrous globular (ii) Outline the difference in structure between a fibrous  and a globular protein. ' shows the ef

Steam treatment Steam treatment of crop residues under pressure has recently opened a new vista for their nutritional improvement especially in the situation when steam availab

Determine the Fransworth 100 Hue Panel Test This is a simple and useful test using colour chips arranged in a particular sequence. Colour deficient patients make errors in arra

Absorption of amino acids and  peptides Generally,  the  dietary proteins are almost comp!etely  digested to their constituent amino acids and these are rapidly absorbed  from

Explain Viruses and their classification? Viruses are living organisms. Viruses are not living organisms. No, the above is not a misprint! In fact, viruses defy the normal c