Correct Answer: B

Rationale: Nausea and vomiting are among the most common and distressing side effects of chemotherapy. Chemotherapy drugs target rapidly dividing cells, including cancer cells, but they also affect healthy cells in the gastrointestinal (GI) tract, triggering the release of chemicals that stimulate the brain's vomiting center. These side effects can occur immediately (acute), be delayed, or even anticipatory, and often require management with antiemetic (anti-nausea) medications to improve the patient's comfort and quality of life during treatment.

Correct Answer: D

Rationale: While chemotherapy does affect normal, healthy cells-particularly those that divide rapidly-it is not "more likely" to kill normal cells compared to cancer cells. Chemotherapy targets rapidly dividing cells, which includes both cancer cells and some normal cells (like those in hair follicles, the gastrointestinal tract, and bone marrow). However, its primary goal is to kill cancer cells, and its effects on normal cells are a side effect, not the main function. Therefore, the statement that chemotherapy is "more likely" to kill normal cells is inaccurate and indicates a need for further teaching.

Correct Answer: B

Rationale: Contact inhibition is a regulatory mechanism that prevents cells from proliferating once they reach a certain density. Normally, when cells grow and touch each other (such as in a monolayer), they stop dividing, maintaining tissue integrity and structure. When contact inhibition is lacking, as in many cancerous cells, cells continue to grow and divide uncontrollably, leading to tumor formation. This loss of regulation is a hallmark of cancerous growth.

Correct Answer: B

Rationale: In polycythemia vera, there is an overproduction of red blood cells, white blood cells, and platelets, which leads to increased blood viscosity and a high risk for thrombosis (blood clot formation). Monitoring the platelet count is a priority because elevated platelet levels contribute significantly to the risk of developing blood clots, which can result in life-threatening complications such as strokes, heart attacks, or deep vein thrombosis (DVT). Therefore, regular monitoring of the platelet count is essential to assess the patient's risk for thrombosis and to guide treatment decisions, such as phlebotomy or medication adjustments to lower platelet levels.

Correct Answer: B

Rationale: An elevated white blood cell (WBC) count, also known as leukocytosis, is most commonly a response to infection. When the body detects an infection, the immune system responds by increasing the production of white blood cells to fight off the invading pathogens. The accompanying symptoms of fever and malaise are typical signs of infection, supporting the likelihood that this patient's health status is related to an infectious process rather than a more serious hematologic condition like lymphoma or leukemia.