Chromosome number
• Each species has definite and constant somatic and genetic chromosome number
• Somatic chromosome number is the number of chromosome found in somatic cells while genetic chromosome number is the number of chromosome found in gametic cells.
• Somatic chromosome are always diploid and are denoted as 2n where as genetic chromosomes are always haploid and are denoted as n
• In human being somatic chromosomes are XX and XY where as genetic chromosome number is X and Y