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

Why do substances react with each other, Why do substances react with each ...

Why do substances react with each other? Chemical reactions occur due to the products of the reaction have less energy than the reactants (drive toward less energy). These reac

Explain the term trans fatty acids, Explain the term Trans fatty acids? ...

Explain the term Trans fatty acids? Plant derived fats and oils contain cis-fatty acids. You may recall reading about the cis and trans isomers in the Nutritional Biochemistry

Explain the carbohydrates and fat requirements during sepsis, Explain the C...

Explain the Carbohydrates and Fat Requirements during Sepsis? Carbohydrates should constitute nearly 60% to 70% of the total energy. Glucose is the primary calorie substrate in

Explain the interaction of vitamin a with proteins, Explain the interaction...

Explain the interaction of vitamin a with Proteins? Proteins: The protein status of an individual influences vitamin A status and transport because an inadequate protein intake

Variations on translation, Which of the following variations on translation...

Which of the following variations on translation would be most disadvantageous for a cell? A) translating polypeptides directly from DNA B) using fewer kinds of tRNA C) having only

What are the major parts of ferns, Q. What are the major parts of ferns? ...

Q. What are the major parts of ferns? Ferns are constituted by small roots that come downwards from the rhizome stem and often horizontalized. The fronds also arise from the rh

Tricuspid annuloplasty-types of surgery, Tricuspid Annuloplasty :  Tr...

Tricuspid Annuloplasty :  Tricuspid valve is evaluated by digital palpation before connecting the patient to cardio pulmonary by pass. Functional regurgitation can be repaire

Define objective of taxonomy -assemblage of knowledge gained, Define Object...

Define Objective of Taxonomy - Assemblage of Knowledge Gained? A second objective of taxonomy is the assemblage of knowledge gained. This is usually in the form of treatises us

Fumonisins, Fumonisins The most recently characterized mycotoxins of an...

Fumonisins The most recently characterized mycotoxins of any major significance in human health are the fumonisins produced by species of Fusarium, such as F. moniliforme. Like

Provide communication between the cells, A) Maintain structural integrity o...

A) Maintain structural integrity of the cell B) Regulate the movement of substances into and out of the cell C) Provide communication between the cells D) ALl of the above

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