Dictionary > Holocentric chromosome

Holocentric chromosome

Definition
noun, plural: holocentric chromosomes
A chromosome in which the entire length of the chromosome seems to act as a centromere
Supplement
The centromere is the dense, constricted region in a chromosome. It contains highly-specialized repetitive DNA sequences (e.g. satellite DNA) that are packaged into heterochromatin. The centromere serves as the site for kinetochore assembly and therefore it is essential during the alignment of the chromosomes at the metaphase plate and the subsequent segregation of chromosomes during cellular division. The presence of the centromere results in the characterization of the chromosomal arms. The arm that is relatively shorter is called p whereas the one that is longer is called q. Based on the position of the centromere, the chromosome may be described as metacentric, submetacentric, acrocentric, telocentric, subtelocentric, and holocentric.
A holocentric chromosome is a chromosome wherein the centromere seems to be the entire chromosome. It is because during mitosis the microtubules attach to a holocentric chromosome along its entire length. In humans, there are no holocentric chromosomes. Nevertheless, this type of chromosome is found in the cells of many animals and plants.1
See also:

Reference(s):

1 Dernburg, A. F. (2001). “Here, There, and Everywhere: Kinetochore Function on Holocentric Chromosomes”. The Journal of Cell Biology, 153 (6): F33–8.


You will also like...

Cells in different stages of meiosis
Meiosis – The Genetics of Reproduction

Meiosis is a form of cell division that creates gametes. It is comprised of two divisions that in the end, the resulting..

Plant Auxins
Plant Auxins – Phototropism & Geotropism

Plants produce hormones to regulate their growth. Auxins, for instance, influence plant growth. Know the role of auxin i..

Control of body movement
Control of Body Movement

Some of the body movements can be controlled at will, others cannot. The body has a motor program, which is the pattern ..

Biological Energy
ATP & ADP – Biological Energy

ATP is the energy source that is typically used by an organism in its daily activities. The name is based on its structu..

Bryophytes
Bryophytes

Bryophytes (nonvascular plants) are a plant group characterized by lacking vascular tissues. They include the mosses, th..

Kidneys
Kidneys and Regulation of Water and Inorganic Ions

The kidneys are responsible for the regulation of water and inorganic ions. Read this tutorial to learn about the differ..