Question

• Describe the various levels of nucleic acid structure in Eukaryotic chromosomes at the molecular level

Answer 1

The DNA is linear when replicated and further packaging occurs in the nucleus by various modifications of the linear DNA. The strands form beta helix structure and DNA then wraps around the histone proteins H2A, H2B, H3 and H4 which are present two each, Therefore around 8 histone proteins DNA binds and this structure is known as the nucleosome and this structure is sealed by H1. Then these nucleosome structures forms loops and becomes more compact and forms the chromosome structure as shown in the figure. In this form the DNA becomes chromosome in the eukaryotic cells.