Aplasia can occur because of riboflavin deficiency?

Correct Answer: B

Rationale: The correct answer is B: FALSE. Aplasia is not directly caused by riboflavin deficiency. Aplasia refers to the failure of an organ or tissue to develop or function normally, while riboflavin deficiency is associated with conditions like glossitis and cheilosis, not aplasia. Riboflavin deficiency primarily affects mucous membranes and skin, not organ development. Therefore, there is no direct causal relationship between riboflavin deficiency and aplasia. Choices A, C, and D are incorrect as they suggest a potential link between riboflavin deficiency and aplasia, which is not supported by scientific evidence.

Correct Answer: A

Rationale: The correct answer is A: Orthochromic Normoblast. This is the most mature normoblast stage before becoming a mature red blood cell. The orthochromic normoblast has a small, condensed nucleus and minimal cytoplasmic basophilia. Basophilic normoblast (B) is an earlier stage with a larger nucleus and more basophilia. Pronormoblast (C) is the earliest stage with a large nucleus and intense basophilia. Polychromatic normoblast (D) is an intermediate stage with a slightly reduced nucleus and residual basophilia. Therefore, A is the most mature normoblast stage among the choices provided.

Correct Answer: A

Rationale: Step 1: Normal Adult Hb A is composed of two alpha and two beta globin chains. Step 2: Hemoglobin A is the most common type of hemoglobin in adults. Step 3: The correct answer, A, is alpha and beta, as confirmed in step 1. Step 4: Choice B is incorrect as epsilon is not a component of Adult Hb A. Step 5: Choice C is incorrect as delta is not a component of Adult Hb A. Step 6: Choice D is incorrect as brotherton is not a known component of hemoglobin.

Correct Answer: C

Rationale: The correct answer is C: IL-3. IL-3 is a multilineage cytokine that stimulates the growth and differentiation of multiple blood cell lineages. It acts on various stem cells to promote the production of different types of blood cells. IL-1 is mainly involved in inflammation and immune response, not multilineage effects. IL-2 primarily regulates T cell growth and function. IL-4 promotes B cell growth and IgE production. Therefore, IL-3 is the correct answer as it is specifically known for its multilineage effects on blood cell development.

Correct Answer: B

Rationale: The correct answer is B: Ferrous. In the heme molecule, iron is present in the ferrous form (Fe2+). This form of iron allows for the binding of oxygen in hemoglobin. Ferro (A) is not a correct term for iron in heme. Ferric (C) refers to the Fe3+ form of iron, which is not found in heme. Apoferritin (D) is a protein that stores iron but is not directly involved in heme synthesis. Therefore, the correct form of iron in the heme molecule is ferrous (B).