Question

What are the two types of genes associated with the regulation of the cell cycle/formation of cancer cells? What are they supposed to do? What happens when they are mutated?

a. Tumor suppressor genes prevent cell division and repair DNA. Mutations lead to uncontrolled cell growth.
b. Proto-oncogenes stimulate cell division when needed. Mutations cause them to become oncogenes, promoting excessive cell division.
c. Apoptosis genes regulate cell death. Mutations inhibit apoptosis, allowing damaged cells to survive.
d. DNA repair genes fix damaged DNA. Mutations in these genes lead to DNA damage accumulation.

Answer 1

The two gene types regulating the cell cycle are tumor suppressor genes and proto-oncogenes, which normally prevent and stimulate cell division, respectively. Mutations in these genes can lead to tumor suppressor genes failing to inhibit, or oncogenes continually promoting, cell division, thus contributing to cancer development.

Step-by-step explanation:

The two types of genes associated with the regulation of the cell cycle and the formation of cancer cells are tumor suppressor genes and proto-oncogenes. Tumor suppressor genes normally work to prevent division of cells with damaged DNA and facilitate DNA repair, acting as a brake in the cell cycle. When mutated, they lose their ability to inhibit abnormal cell growth, leading to uncontrolled cell division. On the other hand, proto-oncogenes are involved in stimulating cell division when necessary, acting like a cell cycle accelerator. These genes can be mutated to become oncogenes, which then promote excessive and unregulated cell division, a hallmark of cancer cells.

In the event of mutations, the balance between these genes is disrupted. The malfunctioning tumor suppressor genes fail to stop cell division, akin to a broken brake, while mutated proto-oncogenes (now oncogenes) continuously encourage cellular proliferation, similar to an accelerator stuck in the on position. The outcome of such unregulated cell division can lead to the formation of tumors and the development of cancer.