Biomedical Engineering: Bridging Medicine and Technology 1st Edition by Veronique Tran,Mark Saltzman

Exercise 19

Humans have a large amount of DNA that is uncoded compared to yeast and bacteria. The human genome contains about 3 billion bases of DNA; this is much more than the 3 million bases in a typical bacterium. The genome of a yeast cell (the simplest eukaryote) is about 14 megabases. Using the following table, calculate the density of genes per unit length of genome in each case. Also, for each cell type, state the fraction of genome that is used to code for proteins (i.e., contains genetic information). Comment on the reasons for the changes in complexity of proteins as well as the percentage of coded genome that is coded in higher organisms.