OCR GCSE Biology A · J247
Specification B2.2c · Paper 1 (Foundation), Paper 3 (Higher)
Revise: Human circulatory systemDirection is the reliable way to distinguish an artery from a vein. It is not correct to define every artery as carrying oxygenated blood or every vein as carrying deoxygenated blood. The vessels linking the heart and lungs provide important exceptions.