Bone marrow responds to iron therapy by increasing erythropoietic activity. Which of the following in bone marrow would most likely indicate erythropoiesis?

Correct Answer: B

Rationale: Rationale: 1. Bone marrow increases erythropoiesis in response to iron therapy. 2. Reticulocytes are immature red blood cells derived from erythroblasts, indicating active erythropoiesis. 3. Myelocytes are precursors of granulocytes, not involved in erythropoiesis. 4. Ring sideroblasts are abnormal erythroblasts with iron granules, not indicative of active erythropoiesis. 5. Target cells are red blood cells with central "target-like" appearance due to excess membrane, not directly related to erythropoiesis.

Correct Answer: C

Rationale: The correct answer is C: Temporary collecting of water in jungles. Anopheles balabacensis is a forest-dwelling mosquito species commonly found in jungle environments. They prefer to breed in temporary water collections such as rainwater puddles, small ponds, or stream edges within the jungle. Breeding in urban areas, drains, or rock pools would not be typical for this species based on its natural habitat preference. Therefore, the most suitable breeding site for this vector in Sabah would be temporary water collections in jungles.

Correct Answer: D

Rationale: The correct answer is D: haemolysis. In thalassemia, there is an abnormality in hemoglobin production leading to the destruction of red blood cells, causing hemolysis. This results in the release of bilirubin, leading to jaundice. Iron deposition in the liver (choice B) is seen in conditions like hemochromatosis, not thalassemia. Viral hepatitis B and C (choices A and C) can cause jaundice, but they are not the commonest cause in thalassemia patients, as hemolysis is the primary mechanism in this population.

Correct Answer: C

Rationale: Basophilic stippling refers to the presence of blue-staining granules in red blood cells, which is a classic finding in chronic lead poisoning due to the inhibition of heme synthesis. In CML, the primary feature is the presence of the Philadelphia chromosome. Myelosclerosis is characterized by bone marrow fibrosis, not basophilic stippling. Iron deficiency anemia typically presents with microcytic hypochromic red blood cells, not basophilic stippling. Therefore, the correct answer is C: chronic lead poisoning.

Correct Answer: D

Rationale: Rationale: Splenectomy is curative in hereditary spherocytosis because it removes the site of red blood cell destruction. The spleen is responsible for filtering out abnormal or damaged red blood cells in this condition. Removing the spleen stops the destruction of spherocytes, leading to an improvement in anemia. Summary of other choices: A: G6PD def. - Splenectomy does not address the underlying enzyme deficiency causing hemolysis. B: ITP - Splenectomy is used in refractory cases of ITP, but not considered curative. C: Thalassemia - Splenectomy can be used to manage complications in thalassemia but does not cure the underlying genetic defect.