Topics:
Animal Physiology, Animal Refresher
Form of Oxygen Transport in Blood (98.5%)
98.5% of oxygen transport in the blood takes place in which form?
- Dissolved in plasma
- Oxyhemoglobin — Correct Answer
- Carbaminohemoglobin
- None of the above
Explanation:
Correct Answer: Oxyhemoglobin
98.5% of oxygen in blood is transported bound to hemoglobin as oxyhemoglobin. Only ~1.5% is dissolved in plasma.
Oxygen Transport Details
- Oxyhemoglobin (98.5%): O₂ binds reversibly to the Fe²⁺ of heme in hemoglobin. Each Hb molecule carries 4 O₂ molecules (one per heme group). 1 gram of Hb carries 1.34 ml of O₂. With normal Hb of 15 g/dL, 100 ml blood carries ~20 ml O₂.
- Dissolved in plasma (1.5%): Very small amount; O₂ has low solubility in water. Directly proportional to PO₂ (Henry's Law).
CO₂ Transport (for comparison)
- Bicarbonate ion (HCO₃⁻): 70% — most important
- Carbaminohemoglobin (Hb-CO₂): 23%
- Dissolved in plasma: 7%
Clinical Note
- In carbon monoxide poisoning, CO competes with O₂ for Hb binding (250× higher affinity) → oxyhemoglobin cannot form → tissue hypoxia despite normal PO₂.
📚 About this Topic — Animal Physiology
This multiple choice question is from Animal Physiology, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Physiology to strengthen your preparation.
