1. Growth and Development of different organisms
National 5 Biology
Key Area 6:
The Need for Transport
(b) Animal Transport Systems
National 4 Biology
Key Area 4
Growth and Development of different organisms

2. By the end of this lesson you will be able to ....
Name the 3 types of blood vessels.
Describe the function of each blood vessel
Describe and compare the structure of each type of vessel

3. arteries veins Blood vessels capillaries
The blood vessels are tubes which carry blood around the body.
They are:
arteries
capillaries
veins

4. Types of Blood Vessels 1:09

5. The ARTERY Arteries carry blood away from the heart.
The artery has a pulse
thick muscle and elastic fibres
the thick muscle can contract to push the blood along.
Carries blood at high pressure.

6. Veins carry blood towards the heart.
The VEIN
Veins carry blood towards the heart.
veins have valves which act to stop the blood from going in the wrong direction.
thin muscle and elastic fibres
body muscles surround the veins so that when they contract to move the body, they also squeeze the veins and push the blood along the vessel.
Carries blood at low pressure

7. Capillaries form networks at organs and tissues
The CAPILLARY
Capillaries link Arteries with Veins
they exchange materials between the blood and other body cells.
Capillaries form networks at organs and tissues
the wall of a capillary
is only one cell thick
The exchange of materials between the blood and the body can only occur through capillaries.

8. Arteries, veins and capillaries
Arteries carry high pressure blood away from the heart. They have smaller lumen and no valves.
Capillaries have thin walls (one cell thick) to allow glucose and oxygen to pass through. Also used to connect arteries to veins.
Veins carry low pressure blood back to the heart. They have thinner, less elastic walls and have valves to prevent backflow of blood.

9. Arteries, Capillaries and Veins
Arteries have a thick muscular wall, veins have a thin muscular wall and capillaries are only 1 cell thick (VERY thin)
Veins are the only vessel to contains valves

10. Use these words to complete your note …..
thick
one cell
networks
low
narrow
wider
towards
large
high
away
valves

11. Arteries have_______, muscular walls, a _______ central channel and carry blood under _____ pressure ______ from the heart.
Veins carry blood under ____ pressure, have thinner walls and a ______ channel. Veins contain _____to prevent the backflow of blood and carry blood ______ the heart.
Capillaries form _______ at organs and tissues and have a wall only ___ _____ thick. They have a _____ surface area allowing exchange of materials.

12. Arteries have_______, muscular walls, a _______ central channel and carry blood under _____ pressure ______ from the heart.
Veins carry blood under ____ pressure, have thinner walls and a ______ channel. Veins contain _____to prevent the backflow of blood and carry blood ______ the heart.
Capillaries form _______ at organs and tissues and have a wall only ___ _____ thick. They have a _____ surface area allowing exchange of materials.
thick
narrow
high
away
low
wider
valves
towards
networks
one cell
large

13. Task: Colour the 3 blood vessels to show the type of blood found in each one
Deoxygenated blood
Oxygenated blood
Get pupils to label all the differences from the table onto this diagram