Every day in an adult human roughly 50-70 billion of your cells die. They may be damaged, stressed, or just plain old – this is normal, in fact it’s called programmed cell death.
To make up for that loss, right now, inside your body, billions of cells are dividing, creating new cells.
And cell division, also called mitosis, requires an army of tiny molecular machines.DNA is a good place to start – the double helix molecule that we always talk about.
This is a scientifically accurate depiction of DNA. If you unwind the two strands you can see that each has a sugar phosphate backbone connected to the sequence of nucleic acid base pairs, known by the letters A,T,G, and C.