Final answer:
Leukemia leads to an overproduction of abnormal white blood cells, which are often nonfunctional, compromising the immune system.
Step-by-step explanation:
Leukemia sufferers have too many abnormal white blood cells (leukocytes). In leukemia, these cells are produced in excess, and this can be either mature leukocytes that fail to die in the case of chronic leukemia, or an overproduction of young, immature leukocytes in acute leukemia. The overproduced leukocytes in both cases are often nonfunctional, which can leave individuals at an increased risk for diseases and infections due to a compromised immune system. The excessive number of abnormal white blood cells in leukemia can interfere with the normal production of red blood cells, platelets, and healthy white blood cells, leading to symptoms such as fatigue, anemia, increased susceptibility to infections, and bleeding tendencies.