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

Tanco beans plant, what are the origin, morphology, active constituents, us...

what are the origin, morphology, active constituents, uses and market preparation of tanco beans

What is reflexive memory, What is reflexive memory? Reflexive memory re...

What is reflexive memory? Reflexive memory relies on the cerebellum and amygdala. Compare among aerobic respiration and anaerobic respiration. Aerobic respiration happens in th

Define calcium requirements of infants, Define Calcium requirements of infa...

Define Calcium requirements of infants? The calcium requirements of young infants are computed from the calcium content of breast milk and volume of breast milk intake. Up to 6

Fats , FATS ( = True Fats, Triglycerides, Neutral Fats) They are es...

FATS ( = True Fats, Triglycerides, Neutral Fats) They are esters of fatty acids and 3-carbon trihydric alcohol glycerol (= glycerine). T rue fat is also called trig

Which statement is false, Which is FALSE? Diastereomers: Select one: ...

Which is FALSE? Diastereomers: Select one: a. Have the same molecular weight b. Have the same connectivity c. Are mirror images d. All of the above e. None of the

Pocket psedocyst-endodontics principles and practice, Pocket Psedocyst : le...

Pocket Psedocyst : lesions present as endodontic origins from canals . It makes lumens resemble granuloma . All lesions lined until root canal or apical foramen communicat

Explain hypertensive disorders of pregnancy, Explain Hypertensive Disorders...

Explain Hypertensive Disorders of Pregnancy? Hypertension may have been existing before pregnancy. Alternatively, a mother may develop hypertension during pregnancy, a pregnanc

Explain about balanus, Explain Balanus The realised niche of Balanus ...

Explain Balanus The realised niche of Balanus is the same as its fundamental niche  Lower limits:   as for fundamental niche. Upper  limits: as for fundamental niche

Explain the importance for a hypothesis, What's the difference between theo...

What's the difference between theory and hypothesis and explain the importance for a hypothesis to be testable and falsifiable in order for the scientific method to be applied?

What is the cell theory, Q. What is the cell theory? Cell theory assert...

Q. What is the cell theory? Cell theory asserts that the cell is the element unit of living beings. Before the discovery of the cell, it was not acknowledged that living bei

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