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

Explain the characteristics of starch granule, Explain the Characteristics ...

Explain the Characteristics of Starch Granule Starch granules, primarily, are made up of amylose (20-30%) and or amylopectin (70-80%) molecules arranged radially. Each granule

Illustrate mitral stenosis and pregnancy, Q. Illustrate Mitral Stenosis and...

Q. Illustrate Mitral Stenosis and Pregnancy ? Since mitral stenosis is often seen in young women, it is not uncommon to see young women with pregnancy complicated by mitral ste

Describe the epithelial cells of the kidney proximal tubule, Epithelial cel...

Epithelial cells of the kidney proximal tubule ?   A.  The sodium-glucose co-transporter in the luminal membrane is responsible for the net flux of glucose from luminal space to

Difference between extraradicular and intraradicular, What is the differenc...

What is the difference between extra. and intraradicular? Extraradicular means there is lesions came from periodontal or from the adjacent tissue and make periapical infection

Breathing and exchanges of gases , What happens to respiratory system in a ...

What happens to respiratory system in a man going up a hill?

Respiration - metabolism of pollen tubes, Respiration - Metabolism of Polle...

Respiration - Metabolism of Pollen Tubes In the unpollinated pistils of Hippeastrum hybridum very high O 2 , tension exists from stigma down through most of the style. During

What is phenylketonuria, Q. What is Phenylketonuria? The essential amin...

Q. What is Phenylketonuria? The essential amino acid phenylketonuria is utilized for tissue protein synthesis and hydroxylated to form tyrosine. The hydroxylation reaction requ

FISHERIES, describe the endoskeleton of fish?

describe the endoskeleton of fish?

Cell surface junctions, CELL SURFACE JUNCTIONS (1 )      Desmosomes (...

CELL SURFACE JUNCTIONS (1 )      Desmosomes (Maculae adherence) - Thickened circular areas on P.M. of adjacent cells with radiating fibrils in cytoplasm. These fibrils calle

#title.examples of classes of vertebrates, how to explain an example from e...

how to explain an example from each class of vertebrate

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