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AQA GCSE Biology Trilogy: The Blood Vessels

The Blood Vessels:

Arteries:

  • Carry blood from the heart to the organs

  • Carry bright-red oxygenated blood

  • Can stretch

  • Have thick walls

    • Containing muscle and elastic fibres

  • Have small lumens

    • The central hole which allows blood to flow

Veins:

  • Carry blood from the organs to the heart

  • Carry purple-red, low-oxygen blood

  • Have thin walls

  • Have valves

    • To make sure blood can only flow in one direction

  • Blood is squeezed by the skeletal muscles

  • Have large lumens

Capillaries:

  • Form a huge network of tiny vessels that link the arteries and the veins

  • Have narrow, thin walls

    • Suited for the diffusion of oxygen and glucose

    • Carbon dioxide can easily pass through

Double Circulation:

Pulmonary Circulation System:

  • Connects the heart and the lungs

  • Allows for gas exchange to take place

Systemic Circulation System:

  • Connects the heart and the cells of the body

  • Allows cells to be provided with oxygen

  • Takes carbon dioxide from the cells

Key Facts:

  • Vital in warm-blooded animals

  • Efficient

  • Ensures all cells are provided with oxygenated blood

The Heart:

Source: https://www.tigermoon.co.uk/products/gcse-science-heart-circulatory-system-a2-poster

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AQA GCSE Biology Trilogy: The Blood Vessels

The Blood Vessels:

Arteries:

  • Carry blood from the heart to the organs

  • Carry bright-red oxygenated blood

  • Can stretch

  • Have thick walls

    • Containing muscle and elastic fibres

  • Have small lumens

    • The central hole which allows blood to flow

Veins:

  • Carry blood from the organs to the heart

  • Carry purple-red, low-oxygen blood

  • Have thin walls

  • Have valves

    • To make sure blood can only flow in one direction

  • Blood is squeezed by the skeletal muscles

  • Have large lumens

Capillaries:

  • Form a huge network of tiny vessels that link the arteries and the veins

  • Have narrow, thin walls

    • Suited for the diffusion of oxygen and glucose

    • Carbon dioxide can easily pass through

Double Circulation:

Pulmonary Circulation System:

  • Connects the heart and the lungs

  • Allows for gas exchange to take place

Systemic Circulation System:

  • Connects the heart and the cells of the body

  • Allows cells to be provided with oxygen

  • Takes carbon dioxide from the cells

Key Facts:

  • Vital in warm-blooded animals

  • Efficient

  • Ensures all cells are provided with oxygenated blood

The Heart:

Source: https://www.tigermoon.co.uk/products/gcse-science-heart-circulatory-system-a2-poster