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2:09 pm
Page 147
Air sacs
B8c/2
Name
Class
The diagram shows an air sac from a lung.
blood
air
blood vessel
?
alveolus
1 What sort of blood vessels are found surrounding air sacs?
2 a Draw some red blood cells on the diagram. Do not shade them in.
b Blood cells contain a chemical called haemoglobin. This chemical changes
colour slightly depending on how much oxygen it is carrying (it is bright
red when carrying a lot of oxygen). Find two coloured pencils, one bright
red and one dark red. In the correct areas, shade some of the red blood
cells dark red and some of them bright red.
3 a On the diagram, draw a labelled arrow showing which direction oxygen
particles are going.
b On the diagram, draw a labelled arrow showing which direction carbon
dioxide particles are going.
c Your two arrows show a process that occurs in the lungs. What is the
name of this process?
d In which part of the blood is carbon dioxide carried?
S
knowledge
Exploring Science
Copymaster File 2
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© Pearson Education Limited 2001
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