PATHOLOGY

Detailed explanation-1: -Veins: Unlike arteries, veins don’t have to carry highly pressurized blood, but they do have to carry large volumes of deoxygenated blood back to your heart. Thin, less elastic walls help them handle high volumes and low pressure. Most veins have valves that open and close.

Detailed explanation-2: -Pressure and flow velocity within veins is low due to their structure and due to the movement of blood against the force of gravity.