<span>Cells control cell division in order to maintain normal cell function. If something happens to the control of the cell division, the healthy cells will divide uncontrollably. These new cells are cancer cells. </span>
The mutations in three genes are responsible for development of cancers:
1. Mutation in proto-oncogenes. Proto-oncogenes normally signal cells to grow and differentiate. Proto-oncogenes can become oncogenes due to mutations which result in the uncontrollable division of the cells.
2. Mutation in tumor suppressor genes. In normal cells, tumor suppressor genes suppress genes essential for cell cycle and that way they prevent uncontrollable cell division. However, after a mutation in these genes, suppression is lost and the cell may progress to cancer.
3. Mutation in stability genes. In normal cells, they have no role either in cell death or growth, but they control mutation rate. Mutation in stability genes results in situation where all genes, including proto-oncogenes and tumor suppression genes, are more frequently mutated.
The correct answer is true. Both intramembranous ossification and endochondral ossification originates from a primary ossification center. The primary ossification center, as the name implies, is the focus where the bone tissue starts ossifying. Primary ossification centers are usually found in the diaphysis of long bones or in the body of irregular bones.
They are a good choice because at any given time, you can find cells that are undergoing mitosis.
After if it ur baby but if u breast feeding ur friends baby if she cant produce milk its before during and after
Answer:
because different cell types can perform different functions
