In a nucleus acids, mutations are changes in the sequence of

Nucleotide

Explanation:

A mutation is a heritable change in the nucleotide sequence of an organism's DNA

advantage of using stem cells in medical research:

1.       it provides medical benefits in the fields of therapeutic cloning and regenerative medicine.

2. it provides great potential for discovering treatments and cures to a variety of diseases including parkinson disease, spinal cord injuries, diabetes, alzheimer’s disease and many more.

3. limbs and organ could be grown in lab from stem cells and then used in transplant or treat illness.

this website is for anybody really not just for girls just saying, also while a lot of males are mean and you know there are the few who are kind and then there's the nice-guys but then theirs also guys like me who are shy we don't get out much because there are people like you who exist who would most likely punch a guy in the face so next time just think about things before you post them to a website where guys and girls can see your question.