1. Which oncogene is most commonly associated with breast cancer?

 A) BRCA1

 B) HER2

 C) MYC

 D) Ras

 Answer: B) HER2. Rationale: HER2 is an oncogene that plays a crucial

role in the development of breast cancer. Overexpression of HER2 is

found in approximately 20% of breast cancers and is associated with

aggressive tumor growth and poor prognosis.

2. What is the function of tumor suppressor genes?

 A) Promote cell division

 B) Suppress cell division

 C) Aid in cell differentiation

 D) Enhance DNA repair mechanisms

 Answer: B) Suppress cell division. Rationale: Tumor suppressor genes

help regulate the cell cycle and ensure that cells do not proliferate

uncontrollably. When these genes are mutated or lost, cells can divide

unchecked, leading to cancer.

3. The presence of which hallmark indicates that cancer cells can evade

apoptosis?

 A) Sustaining proliferative signaling

 B) Evading growth suppressors

 C) Resisting cell death

 D) Inducing angiogenesis

 Answer: C) Resisting cell death. Rationale: One of the hallmarks of

cancer is the ability to resist programmed cell death or apoptosis. This

allows cancer cells to survive and proliferate even when they have

sustained significant damage.

4. What role does the p53 gene play in cancer prevention?

 A) It encodes an oncogene.

 B) It acts as a DNA repair enzyme.

 C) It functions as a tumor suppressor.

 D) It promotes angiogenesis.

 Answer: C) It functions as a tumor suppressor. Rationale: The p53 gene

is known as the "guardian of the genome" because it regulates the cell