2.3.4

Blood Vessels - Veins

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Veins

Veins form when capillaries join up after passing through the body. They transport deoxygenated (contains no oxygen) blood (apart from the pulmonary vein) from the organs back to the heart. They are different to arteries because:

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Thinner walls than arteries

  • The walls are thinner than those found in the arteries as the blood is at a lower pressure.
Illustrative background for Wider cross-section (lumen) than arteriesIllustrative background for Wider cross-section (lumen) than arteries ?? "content

Wider cross-section (lumen) than arteries

  • Low pressure hinders blood flow. This means that veins have a wider cross-section through which blood can flow to counteract this.
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Valves

  • Veins have valves to prevent the backflow of blood.

Jump to other topics

1Cell Biology

2Organisation

2.1Principles of Organisation

2.2Enzymes

2.3Circulatory System

2.4Non-Communicable Diseases

2.5Plant Tissues, Organs & Systems

3Infection & Response

4Bioenergetics

5Homeostasis & Response

6Inheritance, Variation & Evolution

7Ecology

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