Answer: Deficiency of haemoglobin or red blood cells, reducing oxygen-carrying capacity of blood.
- A Excess iron accumulation building up gradually in the bloodstream, causing toxic overload
- B Deficiency of haemoglobin or red blood cells, reducing oxygen-carrying capacity of blood
- C Excess production of white blood cells originating from the bone marrow over time
- D A deficiency of circulating white blood cells that gradually reduces overall immunity
Correct answer: B. Deficiency of haemoglobin or red blood cells, reducing oxygen-carrying capacity of blood
Explanation: Anaemia: reduced haemoglobin or RBC count, reducing blood oxygen-carrying capacity. Causes: iron deficiency (most common), B12/folate deficiency, haemolysis (e.g., malaria, sickle cell), bone marrow failure. Symptoms: fatigue, pallor, breathlessness.
The Plasmodium parasite needs both hosts: the female Anopheles mosquito injects sporozoites while biting (infecting the human liver and RBCs, causing the malaria fever cycle), then picks up gametocytes from an infected person's blood, completing the parasite's sexual stage inside the mosquito.
Concept context
Pathogens, infectious diseases, non-infectious diseases, drugs, cancer, and public health. High NEET importance.