1. blood from the heart gets around the body through blood vessels
There are 3 types of blood vessels
a. ARTERY
b VEIN
c CAPILLARY

2. Elastic layer
Elastic layer
Thin smooth muscle
Thick smooth muscle

3. Arteries carry blood away from the heart.
The ARTERY
Arteries carry blood away from the heart.
the elastic fibres allow the artery to stretch under pressure
thick muscle and elastic fibres
the thick muscle can contract to push the blood along.

4. Copyright Pearson Prentice Hall
Blood Vessels
In the circulatory system, there are three types of blood vessels—arteries, capillaries, and veins. The walls of these vessels contain connective tissue, smooth muscle, and endothelium.
Copyright Pearson Prentice Hall

5. Aorta Transport oxygenated blood from left ventricle to rest of body
Forms the characteristic aortic arch
Largest artery of the body

6. Pulmonary arteries
Brings deoxygenated blood from right ventricle to lungs to uptake oxygen
The ONLY arteries that transport deoxygenated blood
2 pulmonary arteries – one to each lung

7. The CAPILLARY Capillaries link Arteries with Veins
they exchange materials between the blood and other body cells.
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. Copyright Pearson Prentice Hall
Blood Vessels
In the circulatory system, there are three types of blood vessels—arteries, capillaries, and veins. The walls of these vessels contain connective tissue, smooth muscle, and endothelium.
Copyright Pearson Prentice Hall

9. The CAPILLARY A collection of capillaries is known as a capillary bed.
artery
vein
capillaries
body cell

10. Veins carry blood towards from the heart.
The VEIN
Veins carry blood towards from 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.

11. Copyright Pearson Prentice Hall
Blood Vessels
In the circulatory system, there are three types of blood vessels—arteries, capillaries, and veins. The walls of these vessels contain connective tissue, smooth muscle, and endothelium.
Copyright Pearson Prentice Hall

12. Copyright Pearson Prentice Hall
Blood Vessels
Valve open
Large veins contain valves that keep blood moving toward the heart.
Many veins are located near and between skeletal muscles.
Valve closed
Valves closed
Contraction of skeletal muscles helps move blood in veins toward the heart. 
Copyright Pearson Prentice Hall

13. Superior Vena Cava
Brings deoxygenated blood from head and arms to right atrium of heart

14. Inferior Vena Cava
Brings blood from bottom part of body into right atrium of heart

15. Pulmonary Vein
Transports oxygenated blood from the lungs back to the left atrium of heart
The ONLY vein that carries oxygenated blood
2 pulmonary veins – one from each lung

16. Hydrostatic & Osmotic Pressures
The high hydrostatic pressure on the arterial side squeezes water and nutrients out of the capillaries.
Water leaving the capillaries builds up the osmotic pressure because the blood components have become more concentrated.
Towards the venal end, water and waste materials are sucked into capillaries by the osmotic pressure.

17. Arteries and Arterioles
Veins and Venules
Capillaries
Arteries and Arterioles
                                                         
                                                              
                                                        
Function is to carry blood from tissues to the heart
Function is to allow exchange of materials between the blood and the tissues
Function is to carry blood from the heart to the tissues
Thin walls, mainly collagen, since blood at low pressure
Very thin, permeable walls, only one cell thick to allow exchange of materials
Thick walls with smooth elastic layers to resist high pressure and muscle layer to aid pumping
Function : Carry blood towards from heart
Function : Carry blood away from heart

18. Arteries and Arterioles
Veins and Venules
Capillaries
Arteries and Arterioles
Large lumen to reduce resistance to flow.
Very small lumen. Blood cells must distort to pass through.
Small lumen
Many valves to prevent back-flow
No valves
No valves (except in heart)
Blood at low pressure
Blood pressure falls in capillaries.
Blood at high pressure
Blood usually deoxygenated (except in pulmonary vein)
Blood changes from oxygenated to deoxygenated (except in lungs)
Blood usually oxygenated (except in pulmonary artery)

19. Valves Textbook pg 130 Found in the heart and veins
Folds of the inner walls of heart and veins
Shaped like half moons, so called semilunar valves
Function: Prevent backflow of blood.
Textbook pg 130
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20. Unidirectional flow of blood
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21. Vericose Veins
When the valves in the veins near the surface of the skin fail to close properly
Allow blood to accumulate in the veins
Causes vein to bulge (swollen appearance)
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22. Valves fail to close properly
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