Polytene chromosomes, Biology

Assignment Help:

POLYTENE CHROMOSOMES

  1. First seen by Balbiani in salivary glands of larva of Chironomus insect (belongs to order Diptera). Later on such chromosomes observed in several other insects (Drosophila).
  2. Polytene name proposed by Koller.
  3. Polytene Chromosomes composed of many Chromonema (512 to several thousands).
  4. In stained preparation, polytene Chromosomes appear striped with alternate dark and light bands. Dark band have high amount of histone.
  5. Several puffy and swollen areas are seen on polytene Chromosomes. These called Balbiani rings or puffs.
  6. Balbiani rings are site of rapid. m-RNA synthesis.
  7. Ecdyson hormone (moulting hormone) of insects stimulates formation of balbiani rings.
  8. Polytene chromosomes concerned with metamorphosis in insects.

2054_polytene chromosomes.png


Related Discussions:- Polytene chromosomes

How does the hypophysis-corpus luteum negative feedback work, How does the ...

How does the hypophysis-corpus luteum negative feedback work? What is the name given to the atrophied corpus luteum after this feedback process? After ovulation the estrogen an

Explain the management of renewable resources, Explain the Management of Re...

Explain the Management of Renewable Resources? Since the human population has grown, human impacts on the resources that we use, like fisheries and forests, have continued to g

Pattern of limb development, Pattern of Limb Development The first vi...

Pattern of Limb Development The first visible sign of limb development is the appearance of ridge or thickening on each lateral side of the embryo of amniotes. The ridge call

Which term describes a very heart/pulse rate, In studies of human body, whi...

In studies of human body, which of the below terms is used to describe a very rapid heart rate or pulse rate? Is it: a) Tachycardia b) Bradycardia c) Cardiosis d) Myoc

#allsystemsarego., hows does insulin from the pancreas reach the liver?

hows does insulin from the pancreas reach the liver?

Define the anatomical considerations, Define the Anatomical Considerations ...

Define the Anatomical Considerations 1. Neurovascular bundle associated with greater palatine foramen, e.g. palatal root of the upper 1 st molar: Don't do incision at this area

Community-based health insurance systems, Normal 0 false fals...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Acid hydrolysis of non-reducing sugar, Q. Acid Hydrolysis of Non-Reducing S...

Q. Acid Hydrolysis of Non-Reducing Sugar? It involves the acid hydrolysis of non-reducing sugars to reducing sugars. It is also known as the process of inversion. Acid hydrolys

Explain the role of solutions, Explain the role of solutions? Solution...

Explain the role of solutions? Solutions:  A solution consists of a liquid solvent plus substances dissolved in it, called solutes. Solutes may be ions, atoms, or small molec

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