Printer Friendly
Dictionary, Encyclopedia and Thesaurus - The Free Dictionary
3,914,157,270 visitors served.
forum Join the Word of the Day Mailing List For webmasters
?
Dictionary/
thesaurus
Medical
dictionary
Legal
dictionary
Financial
dictionary
Acronyms
 
Idioms
Encyclopedia
Wikipedia
encyclopedia
?

Polyteny
(redirected from polytene)

    Also found in: Dictionary/thesaurus, Medical, Wikipedia 0.01 sec.
Polyteny 

the presence in the nucleus of certain somatic cells of giant multifilamentous (polytene) chromosomes, which are hundreds of times larger than normal chromosomes. Polyteny leads to substantial increase in ploidy of the nuclei (up to 32.768N in Chironomus). Polyteny was first described in 1881 by the French cytologist E. Balbiani. Polytene chromosomes are observed in the cells of larvae of a number of Diptera (Chironomus, Drosophila), in Protozoa, and in some plant cells. Polyteny is the result of repeated replications of chromosomes without subsequent divsion of the cell or its nucleus. Giant chromosomes are characterized by specificity of location of the cross-bands, which permits compilation of chromosome maps and study of the functional activities of each band or group of bands.

REFERENCES

Lobashev, M. E. Genetika, 2nd ed. Leningrad, 1967. Swanson, C, T. Merz, and W. Young. Tsitogenetika. Moscow, 1969. (Translated from English.)

M. M. ASLANIAN
Want to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit the webmaster's page for free fun content.
?Page tools
Printer friendly
Cite / link 		Feedback
Mentioned in?  References in periodicals archive?   Encyclopedia browser?   Full browser?
No references found
 
DNA amplifications, chromatin variations, and polytene chromosomes in differentiating cell of common bread wheat in vitro and root of regenerated plants in vivo.
The problem of giant cells in biology by Nanushyan, E.R.; Skripnikov, A.Y.; Murashov, V.V. / Frontier Perspectives
For example, both chapters on ISH to polytene chromosomes are nearly the same as in the first edition, down to the illustrations and references, and both cover similar material.
In Situ Hybridization Protocols by LINDGREN, VALERIE / Archives of Pathology & Laboratory Medicine
dRan is probably in polytene chromosome band 10A7-9.
Senior Division 2000 by Transactions of the Missouri Academy of Science
 
 
 
Encyclopedia
?

Terms of Use | Privacy policy | Feedback | Advertise with Us | Copyright © 2012 Farlex, Inc.
Disclaimer
All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional.