CLASSIFICATION OF CHROMOSOMES

Chromosomes can be classified on the basis of shape structure and functions:

METACENTRIC: The centromere when divides both the arms p and q equally then that particular shape of chromosome is known as metacentric. Five chromosome pairs are considered metacentric, chromosome 1, 3, 16, 19, 20.

METACENTRIC CHROMOSOME WHOSE p AND q ARMS ARE EQUALLY DIVIDED

SUB META CENTRIC: The centomere when divides p and q arm slightly unequally then that particular shape of chromosome is known as sub meta centric. Majority of human chromosomes are sub metacentric in shape. Mainly appears in L shaped.

SUB META CENTRIC CHROMOSOME IN WHICH THE CENTROMERE DIVIDES BOTH THE ARMS UNEQUALLY

 ACROCENTRIC: Centromere is present at such a position in which the p arm gets very short and q arm very long. Unequal division takes place. Mainly appears in J shaped. All acrocentric chromosomes will be satellite chromosomes. Chromosome 13 21 15 and 22 are acrocentric in shape.

ACROCENTRIC CHROMOSOMES IN WHICH THE CENTROMERE DIVIDES THE ARMS UNEQUALLY

TELOCENTRIC: In telocentric chromosomes, the centromere is located at the end which means it does not have any p arm and have only q arm present. It is not present in human beings, in fact this type of chromosomes are present in very few species around the globe like house mouse.

TELOCENTRIC CHROMOSOMES

Functionally they are classified into 2 groups:

• AUTOSOMES: Chromosomes from 1-22 are autosomes. We can say that the chromosomes which are not sex chromosomes are autosomes. These stores thousands and thousands of genes which is responsible for our physical appearance, behavior etc. These genes codes for proteins used by our body. There morphology is almost same. These are not responsible for our gender determination. 
• SEX CHROMOSOMES: Chromosome 23 is a sex chromosome. This is also known as allosomes. It also have important genes which codes for proteins. This chromosomes are responsible for sex determination, that is, if the 23rd pair is XX then the individual is female and if the pair is XY then the individual is a male. X chromosomes are always present in female body, father's chromosome determines whether the child will be male or female.