4.5.1

The Circulatory System

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The Circulatory System

Complex multicellular organisms require a specialised system for transporting nutrients throughout their bodies and removing waste products.

Illustrative background for HeartIllustrative background for Heart ?? "content

Heart

  • The heart is the centre of the circulatory system.
  • Mammals have a double circulatory system. This means blood flows through the heart twice in one circuit.
    • Deoxygenated blood is pumped to the lungs.
    • Oxygenated blood is pumped around the body.
Illustrative background for Coronary arteriesIllustrative background for Coronary arteries ?? "content

Coronary arteries

  • The heart is a muscle that is constantly contracting and relaxing.
  • The heart muscle needs a constant supply of oxygen for respiration.
  • The coronary arteries supply blood to the heart.
Illustrative background for Pulmonary artery & veinIllustrative background for Pulmonary artery & vein ?? "content

Pulmonary artery & vein

  • Deoxygenated blood is pumped out of the heart to the lungs via the pulmonary artery.
  • Oxygen diffuses into the deoxygenated blood in the lungs and the blood becomes oxygenated.
  • Oxygenated blood flows into the heart from the lungs via the pulmonary vein.
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Aorta & vena cava

  • Oxygenated blood is pumped out of the heart around the body via the aorta.
  • Blood in the aorta is very high pressure to ensure the blood can be pumped to all the tissues in the body.
  • Oxygen dissociates from the blood at respiring cells in the body and the blood becomes deoxygenated.
  • Deoxygenated blood flows into the heart from the body via the vena cava.
Illustrative background for Renal artery & veinIllustrative background for Renal artery & vein ?? "content

Renal artery & vein

  • Oxygenated blood flows out of the aorta to the kidneys.
  • Oxygenated blood enters the kidneys through the renal artery.
  • Oxygen diffuses out of the blood to be used in the kidney cells and the blood becomes deoxygenated.
  • Deoxygenated blood flows out of the kidneys via the renal vein.

Jump to other topics

1Principles of Science I

1.1Structure & Bonding

1.2Properties of Substances

1.3Cell Structure & Function

1.4Cell Specialisation

1.5Tissue Structure & Function

1.6Working with Waves

1.7Waves in Communication

2Practical Scientific Procedures and Techniques

3Science Investigation Skills

4Principles of Science II

4.1Extracting Elements

4.2Relating Properties to use of Substances

4.3Organic Chemistry

4.4Energy Changes in Industry

4.5The Circulatory System

4.6Ventilation & Gas Exchange

4.7Urinary System

4.8Cell Transport

4.9Thermal Physics

4.10Materials

4.11Fluids

5Contemporary Issues in Science

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