As covalent bonds are strong it makes the sugar phosphate backbone a stable molecule which will HV less chances for a mutation while the huydrogen bonds exist for the ease of DNA replication as they are strong in a way but weak for the replication to take place easily.
The answer is: An air conditioner that turns on if the temperature gets too hot.
Even though they hurt you emotionally, Negative feedbacks serve their own important function. They keep your feet on the ground and prevent you from getting too arrogant.
This function is similar as a cooling air conditioner. Hot temperature in the comparison above represent your arrogance and the air conditioner represent the negative feedback.
A eukaryotic cell has a nucleus as well as membrane bound organelles such as the golgi apparatus, endoplasmic reticulum ect.
Explanation:
Cancer occurs in dividing cells only because genetic materials divide into two equal portions during division. This process may be interrupted by carcinogenes or mutagenes to make mutate cells and then render them as cancer cells. In the brain, the cells are differentiated and there is no chance to start division, then how can cancer be found in the brain.
