ATI LPN
Assessment of Hematologic System NCLEX Questions Questions
Question 1 of 5
Laboratory Studies: Red Cell Indices: Measurement of average weight of Hb/RBC. 27-33 pg
Correct Answer: A
Rationale: The correct answer is A: MCH (Mean Corpuscular Hemoglobin). MCH represents the average weight of hemoglobin per red blood cell. The normal range is 27-33 pg. MCV (Mean Corpuscular Volume) measures the average volume of RBCs, not the weight of hemoglobin. MCHC (Mean Corpuscular Hemoglobin Concentration) measures the concentration of hemoglobin in a given volume of packed red blood cells, not the weight of hemoglobin. RDW (Red Cell Distribution Width) measures the variation in RBC size, not the weight of hemoglobin. Therefore, A is correct as it directly relates to the average weight of hemoglobin per red blood cell.
Question 2 of 5
What is the life span of RBC
Correct Answer: A
Rationale: The correct answer is A: 120 days. Red blood cells (RBCs) have a lifespan of around 120 days. This is because they do not contain a nucleus and other organelles, limiting their ability to repair and maintain themselves. RBCs are constantly being produced and replaced by the bone marrow. Choices B, C, and D are incorrect as they do not align with the established scientific knowledge regarding the lifespan of RBCs. A lifespan of 100, 200, or 80 days is not consistent with the typical turnover rate and function of red blood cells in the body.
Question 3 of 5
Chronic Lymphocytic Leukemia is characterized by peripheral blood and bone marrow
Correct Answer: B
Rationale: The correct answer is B: Lymphocytosis. Chronic Lymphocytic Leukemia is characterized by an increased number of mature lymphocytes in the peripheral blood and bone marrow, leading to lymphocytosis. Lymphocytopenia (choice A) is the opposite of lymphocytosis and is not typical in CLL. Neutropenia (choice C) refers to a low level of neutrophils, which is not a characteristic finding in CLL. Thrombocytosis (choice D) is an increased number of platelets, which is not a defining feature of CLL.
Question 4 of 5
At which month of fetal development does the bone marrow become the primary site of hematopoiesis?
Correct Answer: C
Rationale: The correct answer is C, the end of the 6th month. By this time, the bone marrow becomes the primary site of hematopoiesis in fetal development. This is because around this stage, the bones have developed enough to support the production of blood cells. Prior to the end of the 6th month, hematopoiesis mainly occurs in the liver and spleen. Choices A, B, and D are incorrect because by the 2nd, 5th, and end of 7th month respectively, the liver and spleen are still the main sites of hematopoiesis in fetal development.
Question 5 of 5
Which single feature of normal RBCs is most responsible for limiting their life span?
Correct Answer: D
Rationale: The correct answer is D: Loss of nucleus. The absence of a nucleus in red blood cells (RBCs) limits their ability to repair and regenerate, leading to a shorter lifespan. Without a nucleus, RBCs cannot synthesize new proteins or repair damaged DNA, making them more susceptible to wear and tear. The other choices are incorrect because: A: Loss of mitochondria - RBCs naturally lack mitochondria to make space for more hemoglobin, but this feature does not significantly impact their lifespan. B: Increased flexibility of the cell membrane - While flexibility is important for RBCs to navigate through narrow capillaries, it does not directly affect their lifespan. C: Reduction of Hb iron - While iron is crucial for hemoglobin function, a reduction in Hb iron does not directly limit the lifespan of RBCs.