Question

Which of the following statements is not true for cancer cells in relation to mutations?
A. Mutations in proto-oncogenes accelerate the cell cycle.
B. Mutations destroy telomerase inhibitors.
C. Mutations inactivate cell control.
D. Mutations inhibit the production of telomerase.

Answer 1

Hint:Cancer is a disease caused by an uncontrolled division of cells in a part of the body. Abnormal cells divide without control over the cell cycle. Uncontrolled growth of these abnormal cells invades other tissues. It can spread within a body from one organ to others via blood and lymph.

Complete answer:The normal functioning of the cell cycle is regulated by genes called Proto-oncogenes. Formation of the daughter cell from the parent cell is regulated under the surveillance of several checkpoints. Checkpoint of the cell cycle has a key role in detecting defects that occur during processes such as DNA replication or chromosome separation and in response, it arrests the cell cycle until the defects are repaired.
If the mutation of Proto-oncogenes occurs it produces Oncogenes. Oncogenes are responsible for the loss of control over the cell cycle and uncontrolled growth of cells.
So, option A is the correct statement hence, it is an incorrect option for the given question.
Telomerase enzyme carries out replication of telomeres and maintains the chromosome length in the cell. The end replication problem in Eukaryotes is solved because of the presence of the Telomerase enzyme. According to Option B, mutations destroying the telomerase inhibitor will cause cancer. Therefore, B) statement also becomes correct.
According to option C, Mutations inactivate the checkpoints of the cell cycle and cause loss of control over the cell cycle is the correct statement.
If mutations inhibit the production of telomerase it will lead to the shortening of chromosomes during each replication cycle and results in cell death.
Cancer-causing mutations do not inhibit the production of telomerase. So, option D becomes an incorrect statement.
In the given question it is asked which of the following is ‘not true’.
So, the answer to the given question is option D.

Note:Cancer-causing mutations are called Carcinogenic mutations. When mutations are accumulated in the cell it causes Cancer. Substances that are responsible for causing cancer are called carcinogens. Gamma rays, U.V. rays, and tobacco are a few examples of carcinogenic agents.