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

List five advantages of dsme, Q. List five advantages of DSME? Followin...

Q. List five advantages of DSME? Following are the advantages of DSME. It enables the patient to 1. Accept the disease. 2. Gain knowledge about disease, its prevention

Define the phosphorus - the macromineral, Define the Phosphorus - The Macro...

Define the Phosphorus - The Macromineral? The body contains about 620 g (20 moles) of phosphorus. Of this 87% is present in bones. It is thus more widely distributed in the bod

Why could a disease be more serious in a population, Why could a disease be...

Why could a disease be more serious in a population with a low genetic diversity? A population with a low genetic diversity could be more expected to be wiped out by a disease

How to increase the ratio of nadh, Certain conditions such as excessive alc...

Certain conditions such as excessive alcohol consumption can increase the ratio of NADH/NAD+ in the mitochondria. This will directly inhibit which of the following enzymes? -cit

Explain the term antioxidants, Normal 0 false false false ...

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

Protozoa., brief account on classification and general characters of protoz...

brief account on classification and general characters of protozoa

Define the factors effect the quantity of human milk, Define the factors ef...

Define the factors effect the Quantity of Human Milk? A large healthy baby who can vigorously suck will induce and obtain much more milk from its mother than a small, sickly or

Primary prevention of diabetes mellitus, Q. Primary prevention of diabetes ...

Q. Primary prevention of diabetes mellitus? Approaches to Prevention: There are various approaches to prevention. Four levels of prevention related to different stages of a di

What do you mean by crystalline style, What do you mean by crystalline styl...

What do you mean by crystalline style? A rodlike structure in some mollusc stomachs which is made of enzymatic proteins required for digestion. Cilia lining the stomach rotate

Transmembrane voltage, How come that difference of K+ and Na+, which are bo...

How come that difference of K+ and Na+, which are both monovalent cations, creates the difference of the net charge of the membrane at different sides?

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