Name: RNA World
Uploaded: 2019-07-19
Duration: 5 min 49 s
Description: We know our DNA stores information, and the RNA reads it and transmits it. But which one appeared first? Let’s find out how this really works.

Question

Describe the structure of a nucleosome with the help of a well-labelled diagram.

Accepted Answer

Nucleosomes are the repeating units of chromatin present in the nucleus (organelle). It is formed when a negatively charged DNA is wrapped around the positively charged histone octamer. The histone proteins are organised themselves to make a unit of eight molecules known as histone octamer.

There are five types of histone proteins- H1, H2A, H2B, H3, and H4. Four of these types (H2A, H2B, H3, and H4) occur in pairs to produce histone octamer called nu body or core of nucleosome. DNA connecting the adjacent nucleosome is called linker DNA which bears H1. One nucleosome contains approximately 200 base pairs of DNA helix. The nucleosomes in chromatin look like 'beads-on string' when observed under an electron microscope.

Describe the structure of a nucleosome with the help of a well-labelled diagram.

Important Questions on Molecular Basis of Inheritance

Learn and Prepare for any exam you want !