Dictionary > T-banding

T-banding

Definition
noun
(cytogenetics) A modified reverse chromosomal banding technique wherein the telomeres are strongly stained as the faint R-banding still occurs over the rest of the chromosome
Supplement
Cytogeneticists use banding techniques to determine the characteristic pattern of light and dark bands on a chromosome under a microscope. They make use of diagrams referred to as chromosome ideograms to determine the relative sizes and the banding patterns of chromosomes. By applying specific stains, the banding patterns become apparent. The different types of banding are Giemsa (G-) banding, reverse (R-) banding, constitutive heterochromatin (C-) banding, quinacrine (Q-) banding, Nucleolar Organizer Region (NOR-) banding, and telomeric R (T-) banding.
Reverse banding is a banding technique wherein the banding pattern is the reverse of G-banding (thus, the name). In G-banding, the banding pattern is a series of light and dark bands on a chromosome. Regions in the chromosome that stain lightly tend to be euchromatic, rich with guanine and cytosine and more transcriptionally active whereas regions that stain darkly tend to be heterochromatic, rich with adenine and thymine and less transcriptionally active. In reverse banding, the dark regions of the chromosomes tend to be euchromatic and rich in guanine and cytosine whereas the light regions tend to be heterochromatic and rich in adenine and thymine. Thus, reverse banding produces bands that are complementary to G-bands.
In T-banding, the telomeres are strongly stained as the faint R-banding still occurs over the rest of the chromosome (thus, the name).
See also:


You will also like...

Lotic community of algal species
Lotic Communities & Algae

Lotic communities have conditions that are rather harsh for typical plants. Thus, the diversity of plant species in loti..

Hormone Production
Hormone Production

Hormones are chemical messengers produced by specialized glands and they were produced by switching on the genes designe..

Population Growth and Survivorship
Population Growth and Survivorship

This lesson looks at population attributes, regulation, and growth. It also covers population genetics, particularly gen..

Human Nervous System
The Human Nervous System

The nervous system is essentially a biological information highway. This tutorial gives an overview of the nervous syste..

bryophyte - sporophyte and gametophyte
Meiosis and Alternation of Generations

Plants are characterized by having alternation of generations in their life cycles. This tutorial is a review of plant m..

Adaptation Tutorial
Adaptation Tutorial

Adaptation, in biology and ecology, refers to the process or trait through which organisms or the populations in a habit..