Mitosis is a part of the cell cycle when replicated chromonsomes are separated into two new nuclei.
What does the problem says
Helicase, DNA polymerase, Ligase and Primase. These are the ones we learned I don't know if there are more.
They are said to be “denser” than air. what happens is that light slows down when it passes from the less dense air into the denser glass of water. this slowing down the ray of light also causes the ray of light to change directions. it is the change in the speed of the light that causes refraction.
The answer is 4. Hope this helps
