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

Bovine spongiform encephalopathy (bse), Normal 0 false fal...

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

DIGESTION, GIVE ADETAILED ACCOUNT OF THE VARIETY OF FUNCTIONS PERFORMED BY ...

GIVE ADETAILED ACCOUNT OF THE VARIETY OF FUNCTIONS PERFORMED BY THE LIVER

Explain different photic energy frequencies, What is an example of a lab ex...

What is an example of a lab experiment that shows the variation of the photosynthesis efficiency in relation to different photic energy frequencies to which the reaction is exposed

CDNA library, How to make and why one needs to make cDNA library??

How to make and why one needs to make cDNA library??

Assignment., what are the sub- headings in energy?describe energy in biolog...

what are the sub- headings in energy?describe energy in biology?

Eggs of eutheria, EGG S OF EUTHERIA This egg is small & round. The dim...

EGG S OF EUTHERIA This egg is small & round. The dimeter of human egg is 0.1 mm. It has very little amount of yolk but they are also as alecithal egg. The egg is covered

Define essential parts of photocolorimeter - sample cuvettes, Define Essent...

Define Essential Parts of Photocolorimeter - Sample Cuvettes? For accurate and precise reading, cuvette must be transparent, clean, devoid of any scratches and there should be

Reaction - processes in succession, Reaction - Processes in Succession ...

Reaction - Processes in Succession This is the most important stage in succession. The mechanism of modification of environment, through the influence of living organisms on i

Axon, Axon: Axon is a projection from the cell body. Each neuron ...

Axon: Axon is a projection from the cell body. Each neuron has only one axon. Unlike dendrites, axons are very long and are usually unbranched structures. The axon

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