Question

What is the cause of discontinuous synthesis of DNA on one of the parental strands of DNA? What happens to these short stretches of synthesised DNA?

Answer 1

Okazaki fragments:

There is discontinuous synthesis of DNA on the lagging strand because the DNA polymerase moves from 5’ to 3’ direction only.

The lagging strand runs from 3’ to 5’ direction.

So, by looping back mechanisms small stretches of DNA are synthesized.

The short stretches of synthesized DNA called okazaki fragments are later joined together by DNA ligase.