Question

Two types of genes play major roles in regulating the cell cycle: Proto-oncogenes encourage cell division, while tumor-suppressor genes inhibit cell division. The balance between these two types of genes may be disrupted by naturally occurring or environmentally caused A) proteins. B) mutations. C) inhibitors. D) cell cycle clocks.

Answer 1

the answer is B, mutations

Answer 2

Answer:

B. Mutations

Explanation:

Mutations are the random changes in the genome of the organisms. Mutations in proto-oncogene or tumor suppressor gene can result in loss of balance between these two types of genes. It causes loss of control over cell cycle. Mutations can be caused by natural or environmental factors such as X-rays, ultraviolet radiations as well as certain toxins.