... , as the name suggests, the triplication of the 21st chromosome. Genes which, basically, contain the blueprints for our cellular structure, are grouped along rod-like structures called chromosomes. Normally, the nucleus of each cell contains 23 pairs of chromosomes, half of which are inherited from each parent. In Down syndrome (DS), however, the cells usually contain not 46, but 47 chromosomes ... gene (alleles) may be present. (Example: the genetic information for eye color is a "gene;" the variations for blue, green, etc. are the alleles.) Human cells divide in two ways, the first bei...

• Word Count: 3980
• Approx Pages: 16
• Has Bibliography
• Grade Level: Undergraduate