NADPH is a product of the hexose monophosphate pathway (HMP) in the red blood cell. The NADPH is used for the

Correct Answer: B

Rationale: The correct answer is B: Reduction of glutathione. In the hexose monophosphate pathway (HMP), NADPH is generated, which serves as a reducing agent. This NADPH is crucial for reducing oxidized glutathione back to its reduced form, maintaining cellular antioxidant defense. This process helps to protect cells from oxidative damage and maintain redox balance. Now, let's summarize why the other choices are incorrect: A: Synthesis of fatty acids - NADPH is indeed involved in fatty acid synthesis, but in the context of red blood cells, the primary role of NADPH is in reducing glutathione. C: Formation of ATP - NADPH is not directly involved in ATP synthesis. ATP is primarily produced through processes like glycolysis and oxidative phosphorylation. D: Removal of oxygen radicals - While NADPH indirectly contributes to the removal of oxygen radicals through its role in reducing glutathione, it is not the primary function of NAD

Correct Answer: B

Rationale: The correct answer is B: Absolute lymphocytes. In CLL, the most important diagnostic criterion is an absolute lymphocyte count of more than 5,000 cells per microliter in the peripheral blood. This is a key feature of CLL and distinguishes it from other conditions. Hypogammaglobulinemia (choice A) may occur in CLL but is not as specific for diagnosis. Male predominance (choice C) is a general characteristic of CLL but is not a diagnostic criterion. Presence of enlarged lymph nodes (choice D) is a common manifestation of CLL but not the most important criteria for diagnosis.

Correct Answer: D

Rationale: The correct answer is D because heparin binds to antithrombin III, enhancing its ability to inactivate thrombin. This prevents the conversion of fibrinogen to fibrin, thereby inhibiting blood clot formation. Choice A is incorrect because vitamin K-dependent clotting factors are not directly affected by heparin. Choice B is incorrect because heparin does not prevent the activation of platelets, rather it affects the coagulation cascade. Choice C is incorrect as heparin does not directly prevent platelet aggregation, which is more related to antiplatelet agents like aspirin.

Correct Answer: D

Rationale: The correct answer is D because the Philadelphia chromosome is found in myeloid (not lymphoid) cells in Chronic Myeloid Leukemia (CML). This is due to a reciprocal translocation between chromosomes 9 and 22, resulting in a shortened chromosome 22q, not chromosome 22 itself. Choice A is incorrect because the long arm of chromosome 22 is affected. Choice B is incorrect as Philadelphia chromosome-negative cases can have a favorable prognosis. Choice C is incorrect as the presence of the Philadelphia chromosome is diagnostic of CML.

Correct Answer: C

Rationale: The correct answer is C: pernicious anemia. Pernicious anemia is a macrocytic anemia caused by vitamin B12 deficiency, leading to large red blood cells. Sideroblastic anemia (A) is a type of microcytic anemia due to ineffective iron utilization. Thalassemia (B) causes microcytic anemia due to decreased production of hemoglobin. Lead poisoning (D) can also lead to microcytic anemia by disrupting heme synthesis. Therefore, pernicious anemia is the only choice that does not produce microcytic anemia.