What is the role of platelets in the body, which can be affected by chemotherapy?

Platelets, or thrombocytes, play a crucial role in the body primarily in the process of hemostasis, which is essential for blood clotting. When a blood vessel is injured, platelets are activated and aggregate at the site of injury. They release various substances that help to form a stable clot, which prevents excessive bleeding. This process is vital for wound healing and maintaining the integrity of the circulatory system.

Chemotherapy can significantly impact platelet production and function, as it often destroys rapidly dividing cells, which includes the megakaryocytes in the bone marrow that produce platelets. As a result, patients undergoing chemotherapy may experience thrombocytopenia, a condition characterized by low platelet counts, leading to increased risk of bleeding and bruising.

In contrast, the other options focus on different physiological roles: oxygen transport is primarily the function of red blood cells, infection fighting is mainly undertaken by white blood cells, and blood sugar regulation is managed by hormones such as insulin. Hence, helping in blood clotting accurately captures the essential role of platelets in the body, especially in the context of the effects of chemotherapy.