Question

a patient receives a stem cell transplant after chemotherapy. what is the purpose of this procedure?
to change the patient’s dna.
to prevent the patient from getting infections.
to increase the patient’s energy levels.
to help the patient produce new red blood cells, white blood cells, and platelets.

Explanation:

Step1: Understand stem cell function

Stem cells can differentiate into various cell types. After chemotherapy, the patient's blood - forming cells (which produce red blood cells, white blood cells, and platelets) may be damaged.

Step2: Analyze each option

• Option1 (To change the patient's DNA): Stem cell transplant is not about changing DNA in this context. DNA change is not the main purpose here.
• Option2 (To prevent the patient from getting infections): While new white blood cells (which help fight infections) may be produced, this is a partial outcome. The overall purpose is broader.
• Option3 (To increase the patient's energy levels): This is a secondary effect (if any) and not the core purpose.
• Option4 (To help the patient produce new red blood cells, white blood cells, and platelets): Stem cells can differentiate into blood - forming cells. After chemotherapy - induced damage to the patient's hematopoietic system, the stem cell transplant provides cells that can regenerate the blood cell population (red blood cells for oxygen transport, white blood cells for immunity, and platelets for clotting).

Answer:

To help the patient produce new red blood cells, white blood cells, and platelets.