Human Immunity and Blood

Diabetics who manage their condition through diet or oral medication (not insulin) are generally eligible to donate blood, provided the condition is well-controlled. Insulin-dependent diabetics are usually deferred because of the stricter medical monitoring required and potential complications.

Hematological malignancies (blood cancers) affect the blood, bone marrow, and lymphatic system including lymph nodes. These cancers include leukemias, lymphomas, and myelomas which originate in these tissues and disrupt normal blood cell production. Blood, bone marrow, and lymph nodes are all integral parts of the hematopoietic system.

Hematological malignancies are cancers of the blood-forming tissues, primarily blood and bone marrow. Blood (A) and bone marrow (B) are correct as they are the sites of blood cell production and maturation. Liver (C) is not a hematological organ, and D (All the above) would only be correct if C were also correct.

Both Chronic Lymphocytic Leukemia (CLL) and Chronic Myelogenous Leukemia (CML) are cancers of white blood cells. CLL affects the lymphoid lineage while CML affects the myeloid lineage, but both involve malignant proliferation of white blood cells.

Acute leukemia is characterized by rapid proliferation of immature blast cells in the bone marrow. While white blood cell count may be elevated, the defining feature is the accumulation of immature, non-functional cells (blasts) rather than just an increase in normal WBCs or RBCs.

Aleukemic leukemia is a specific condition where leukemic cells are present in the bone marrow but do not significantly circulate in peripheral blood, resulting in normal or low white blood cell counts on routine blood tests. This makes detection challenging without bone marrow examination.

Blood group O individuals can ONLY receive blood from other O group individuals because they have both anti-A and anti-B antibodies in their plasma. Receiving A or B blood would cause a dangerous transfusion reaction. While O is called the 'universal donor' (can give to anyone), they can only receive from other O donors. This is fundamental transfusion medicine.

Leukemia is a cancer of the body's blood-forming tissues, including the bone marrow and lymphatic system. It specifically involves abnormal production of white blood cells, which is correctly stated in this question.

Type O blood is the most common blood type globally, with O positive and O negative making up nearly half of the world's population. O negative is particularly valuable as the universal donor for emergency transfusions. A, B, and AB are less prevalent.

The bone marrow is remarkably productive, manufacturing approximately 10 million red blood cells every second to maintain normal blood counts. This continuous production is essential because red blood cells have a lifespan of only about 120 days. The body must constantly replenish its supply to ensure adequate oxygen transport throughout the body.

Blood group O (especially O negative) is called the universal donor because it lacks A, B, and Rh antigens on red blood cells. This means it can be transfused to patients with any blood type without triggering an immune reaction. AB positive is the universal recipient, not donor.

AB blood group individuals are universal recipients because they have both A and B antigens on their red blood cells and no anti-A or anti-B antibodies. This allows them to receive blood from any group (A, B, AB, or O) without adverse reactions. O group individuals are universal donors, not recipients.