Question

on the basisi of lenght and centromere position human chromosome placed in how many group

Answer 1

Structure and Function of the Centromere

Centromeres consist of a complex combination of proteins and DNA. They are essential to the division of cells and ensure the accurate segregation of chromosomes. Studies have demonstrated that chromosomes without centromeres segregate randomly and are eventually lost from cells. In contrast, chromosomes that have multiple centromeres can be subject to fragmentation.

Metacentric Chromosomes

Metacentric chromosomes have the centromere in the center, such that both sections are of equal length. Human chromosome 1 and 3 are metacentric.

Submetacentric Chromosomes

Submetacentric chromosomes have the centromere slightly offset from the center leading to a slight asymmetry in the length of the two sections. Human chromosomes 4 through 12 are submetacentric.

Acrocentric Chromosomes

Acrocentric chromosomes have a centromere which is severely offset from the center leading to one very long and one very short section. Human chromosomes 13,15, 21, and 22 are acrocentric.

Telocentric Chromosomes

Telocentric chromosomes have the centromere at the very end of the chromosome. Humans do not possess telocentric chromosomes but they are found in other species such as mice.