Definition for Chromosomes 9
From Biology Forums Dictionary
Chromosome 9 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome, as they normally do with all chromosomes. Chromosome 9 spans about 145 million base pairs of nucleic acids (the building blocks of DNA) and represents between 4 and 4.5 percent of the total DNA in cells.
Identifying genes on each chromosome is an active area of genetic research. Because researchers use different approaches to predict the number of genes on each chromosome, the estimated number of genes varies. Chromosome 9 likely contains between 800 and 1,200 genes.