Label your diagram: Discuss: What are the differences between veins, arteries and capillaries? Why do they have these differences?

Arteries:  Carry blood carrying O 2 away from the heart to the cells  Have narrow diameter to create high blood pressure  Have thick walls to cope with the high pressure Veins:  Take blood carrying CO 2 back to the heart  Have thin walls and wide diameter because blood pressure is much lower Capillaries:  Connect arteries and veins – lots of them to create large surface area  They are one cell thick which allows O 2 and CO 2 to pass through easily to the cells for respiration

Worksheet: Transport for respiration Do not write on the sheet Hand it back in at the end of the lesson!

Worksheet: Transport for respiration 1)Plasma (not a TV...) carries water around the body, and glucose is dissolved in this plasma 2)Red blood cells carry the oxygen in the blood 3)Haemoglobin is the chemical inside the blood which carries the oxygen 4)Arteries carry “oxygenated” blood away from the heart to our cells. Veins carry “de-oxygenated” blood (containing carbon dioxide) from the cells back to the heart and lungs 5)“Well adapted” means “suited” 6)Capillaries lie in between arteries and veins and they allow O 2 and CO 2 to pass in to the cells. They can do this because they are very thin – only one cell thick 7)Red blood cells are well adapted for carrying O 2 because they are flexible and their shape can carry a lot of haemoglobin