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

Show the list of symptoms, Q. Show the list of symptoms? The list of sy...

Q. Show the list of symptoms? The list of symptoms includes: • Bulky, pale, loose, greasy and foul smelling stools. • Anorexia, feeling of fullness, pain abdomen. The

Sulphur (s) - macronutrients, Sulphur (S) - Macronutrients Sulphur is ...

Sulphur (S) - Macronutrients Sulphur is present in the soil in inorganic and organic forms. In most soils organically bounds is the major S reservoir. The inorganic forms of S

Explain purpose of therapeutic dietary adaptations, Purpose  of  Therapeuti...

Purpose  of  Therapeutic Dietary Adaptations A therapeutic diet is a quantitative/ qualitative modified version of a basic nutritious diet which has been tailored to suit the c

State the transmission of visual sensation, State the Transmission of Visua...

State the Transmission of Visual Sensation This process takes place in the visual pathway from the retina to the visual cortex. 'The impulse originating in the retina travels a

Define in brief about the term - mri, Define in brief about the term - MRI ...

Define in brief about the term - MRI MRI is a more recent development that was initially introduced as a rival to CT. The technique itself is complex, relying on measurement o

Advance techniques for construction of earthquake resistant , The conventio...

The conventional approach to design earthquake resistant building is based upon equipping the building with stiffness, strength and deformation due to elasticity which can afford a

Action of light the basis of the photosynthesis process, Is it correct to c...

Is it correct to consider water decomposition by the action of light the basis of the photosynthesis process? Besides ADP photophosphorylation, photic energy is also responsibl

Initiation codon, Initiation Codon is the codon at which the translation o...

Initiation Codon is the codon at which the translation of a polypeptide chain is initiated. This is generally the first AUG triplet in the mRNA molecule from 5' end, where the rib

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