Question

with reference to the role of oncogenes, explain how the normal controls over the cell cycle can be lost.

Answer 1

When we say oncogenes, these are genes that has the potential to cause cancer. These often undergo mutation and are expressed in very high levels. With this, the normal controls over the cell cycle can be lost. When the normal controls over the cell cycle is lost, the cells would uncontrollably divide, grow and then form tumors. These cells no longer undergo the programmed cell death or also known as apoptosis. Hope this answer helps.

Answer 2

#1) With reference to the role of oncogenes, explain how the normal controls over the cell cycle can be lost.

Answer: The way that cell cycle can be lost is by going through changes in the activity of cell cycle regulators. Cancer causes different types of mutations. There are two types of cell cycle regulators that can promote the development of cancer:

-Positive Regulators that can be over activated (become oncogenic).
-Negative Regulators (tumor suppressors) which can be inactivated.

I hope it helps, Regards.