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

Use of syphilis in pregnancy, Syphilis in Pregnancy Syphilis in pregna...

Syphilis in Pregnancy Syphilis in pregnant women should be treated with penicillin in doses appropriate to the stage of the disease. When pregnant women with syphilis are alle

Explain the the use of soy protein in food industry, The use of soy protein...

The use of soy protein concentrates in different applications in food industry is highlighted herewith. a. Bakery products Unlesss higher protein fortification leve

Define methodology for half and full saturation test, Define Methodology fo...

Define Methodology for Half and Full Saturation Test? 1. Take 5 ml each of starch and dextrin solutions, add 5 ml of saturated solution of ammonium sulfate. Shake thoroughly an

Diabetes mellitus management after open heart surgery, Diabetes Mellitus Ma...

Diabetes Mellitus Management after Open Heart Surgery :  Diabetic patients undergoing coronary artery bypass surgery who are on oral hypoglycemic drugs are pre operatively s

How different is growth according to the biotic potential, How different is...

How different is the growth according to the biotic potential of a viral population from the growth according to the biotic potential of a bacterial population? The growth cur

Radiographic evaluation - criteria for endosteal implants, Radiographic Eva...

Radiographic Evaluation - criteria for endosteal implants Surgical and interventional imaging involves imaging the patient  during and immediately after surgery and during the

How many chromosomes and chromatin strands, Drosophila has 4 bivalents (hom...

Drosophila has 4 bivalents (homologous chromosomes) formed at Meiosis I. How many chromosomes and chromatin strands are present in each of the following stages- Anaphase of mito

Eyeball - choroid, CHOROI D - Thin, net like made up of connective ...

CHOROI D - Thin, net like made up of connective tissue, rich in blood vessels. Pigment present, red in rabbit, brown or black in man. It reduces internal reflection.

Explain seed gums, Seed gums Polysaccharides derived from plants and se...

Seed gums Polysaccharides derived from plants and seeds have been in use for thousand of years. Seed gums are a group of polysaccharides with the following properties: S

Explain cidofovir, Cidofovir (Vistide) IV cidofovir given once weekly ...

Cidofovir (Vistide) IV cidofovir given once weekly for 2 weeks and then once every 2 weeks for maintenance therapy can delay progression of CMV retinitis in patients with AIDS

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