What is genome?

A genome is an organism’s entire single set of DNA which have all the information need for an organism to grow”.

Image credit: www.nature.com

The genome consists of all the genes in each cell. Remember each and every cell of our body has a same genomic composition, except germ cells.

Genes are organized on chromosome during the metaphase stage of cell division, but in interphase, DNA is unorganized and not attached to any of protein. It looks like dark and light region as heterochromatin and euchromatin region respectively.

Heterochromatin regions are tightly packed DNA sequences. It is assembled more tightly with histone and appears darkly. While the euchromatin region is loosely packed and appears as a light region. 

The human genome is made up of 3.2 billion base pair. The term genome is coined by Hans Winkler in 1920. When we are talking about the genome, it includes coding and non-coding both type of sequences.

If we compared it with a computer, a memory storage of computer include RAM and ROM  both types of memory is a whole storage of a computer. Similarly, the genome contains both coding and non-coding sequences. Additionally, mitochondrial DNA is also included as a part of the genome in animals while mitochondrial and chloroplast DNA are included as a part of the plant genome.

Size of genome varies from organism to organism, bacteria has the smallest genome size, while humans and other higher organism has a complex and large genome size.

Article written by: Tushar Chauhan 

 

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