Topics:
Animal Physiology, Animal Refresher
Venous vs Arterial Blood – pH Comparison
Venous blood is more __________ than arterial blood.
- Acidic — Correct Answer
- Alkaline
- Deoxygenated only (no pH difference)
- Watery
Explanation:
Correct Answer: Acidic
Venous blood is more acidic than arterial blood due to the higher content of CO₂ in venous blood.
pH Comparison
- Normal blood pH: 7.4
- Arterial blood pH: 7.4
- Venous blood pH: 7.36 (slightly more acidic)
Why is Venous Blood More Acidic?
- Tissues produce CO₂ as a metabolic byproduct → CO₂ enters venous blood.
- CO₂ + H₂O ⇌ H₂CO₃ ⇌ H⁺ + HCO₃⁻ (carbonic acid dissociation).
- The increase in H⁺ ions lowers pH → venous blood is more acidic.
- 70% of CO₂ is transported as bicarbonate (HCO₃⁻) in plasma.
- 23% as carbaminohemoglobin (inside RBC).
- 7% dissolved in plasma.
Additional Fact
Blood cells (RBCs) are more acidic than blood plasma because they contain CO₂ in the form of carbaminohemoglobin.
📚 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.
