Question

About how much of the DNA in a eukaryotic cell is expressed at any one time:

Options

• 1 per cent

• 20 per cent

• 50 per cent

• 80 per cent

Answer 1

1 per cent

Explanation:

In a typical eukaryotic cell, only a very small fraction of the total DNA is expressed as functional proteins at any given time. While current estimates suggest that only about 1 to 2 per cent of the human genome consists of protein-coding exons, the actual amount of DNA being transcribed in a single specific cell type is even more limited. Most of the genome consists of non-coding regions, regulatory elements, or genes that are “turned off” because they are not needed for that specific cell’s particular function.