Chromosomes have been classified into six categories based on centromere position-M, m, sm, st, t, T, of which only M (isochromosome) and T (telocentric) can be identified quickly with certainty.
What is the basic function of chromosomes?
The most important function of chromosomes is to carry the basic genetic material – DNA. DNA provides genetic information for various cellular functions. These functions are essential for growth, survival, and reproduction of the organisms. Histones and other proteins cover the Chromosomes.
How are chromosomes classified in the human body?
Females have two copies of the X chromosome, while males have one X and one Y chromosome. The 22 autosomes are numbered by size. The other two chromosomes, X and Y, are the sex chromosomes. This picture of the human chromosomes lined up in pairs is called a karyotype.
How are chromosomes classified based on the position of centromere Class 11?
Depending upon the position of the centromere, the chromosomes are classified as follows (i) Acrocentric chromosome Centromere sub-terminal, anaphasic stage J-shaped. (ii) Sub-metacentric chromosome The centromere is sub-median and the anaphasic chromosome appear L-shaped.
What are the 4 types of chromosomes?
On the basis of the location of the centromere, chromosomes are classified into four types: metacentric, submetacentric, acrocentric, and telocentric.
What are the 3 ways to classify a chromosome?
In a given species, chromosomes can be identified by their number, size, centromere position, and banding pattern. In a human karyotype, autosomes or “body chromosomes” (all of the non–sex chromosomes) are generally organized in approximate order of size from largest (chromosome 1) to smallest (chromosome 22).
What are the 24 chromosomes?
The autosomes are normally present in pairs. The sperm contributes one sex chromosome (X or Y) and 22 autosomes . The egg contributes one sex chromosome (X only) and 22 autosomes . Sometimes microarray is referred to as 24-chromosome microarray : 22 chromosomes, and X and Y are counted as one each, for a total of 24.
What are chromosome 2 traits?
Individuals with this chromosome abnormality often have developmental delay, small head size (microcephaly), slow growth before and after birth, heart defects, and distinctive facial features. The severity of symptoms typically depends on how many and which types of cells contain the ring chromosome 2.
What do you mean by Acrocentric chromosome?
Acrocentric chromosome: A chromosome in which the centromere is located quite near one end of the chromosome. Humans normally have five pairs of acrocentric chromosomes.