This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Unknown
Decreased Q2 carrying capacity and Normal PO2 is a feature of : 
Select and explain. 
A. Anemic hypoxia, B. Histotoxic hypoxia, C. Stagnant hypoxia, D. Hypoxic hypoxia
A: Anemic hypoxia
Answer: A: Anemic hypoxia 
Explanation: Subnormal level of hemoglobin causes decreased oxygen – carrying capacity of the blood. This in turn initiates compensatory physiologic adaptations such as :
o Increased release of oxygen from hemoglobin. o Increased blood flow to the tissues.
o Maintenance of the blood volume ; and
o Redistribution of blood flow to maintain the cerebral blood supply.
o Eventually, however, tissue hypoxia develops causing impaired functions of the affected tissues.