Veins and arteries are both types of blood vessels in your body, but they have different jobs and structures. Here’s how they differ:
1. Function:
- Arteries carry blood away from the heart to the rest of the body. Most arteries carry oxygen-rich blood.
- Veins carry blood back to the heart. Most veins carry oxygen-poor blood.
2. Structure:
- Arteries have thick, elastic walls because they need to handle high pressure from the heart pumping blood.
- Veins have thinner walls and bigger inside space (lumen) because the blood pressure in veins is lower.
3. Valves:
- Veins have valves to prevent blood from flowing backward since the blood is moving at a lower pressure and often against gravity.
- Arteries generally don't have valves because the blood is pumped at high pressure in one direction.
Summary: Arteries carry oxygen-rich blood away from the heart with thick walls and high pressure; veins carry oxygen-poor blood back to the heart with thinner walls and valves to help blood flow.