What does blood have in it?
•In pairs quickly come up with a few
ideas on what you think blood consists
of
• Write these ideas on your show me
board
• You have 5 minutes
Blood
The Human Circulatory System
What does the heart do?
•The heart is a muscle that pumps
blood around the body
•It pumps oxygenated blood from the
lungs around the body
•It pumps deoxygenated blood from the
body back to the lungs
There are different types
of blood vessels
Differences between
arteries and veins
Arteries
Veins
All arteries carry blood away
from the heart.
Arteries carry blood under
high pressure.
Arteries have a pulse.
No valves present.
Most carry oxygenated
blood.
Thick layer of muscle and
elastic fibres in wall.
Small lumen
All veins carry blood back to
the heart
Veins carry blood under low
pressure.
Veins do not have a pulse.
Valves present.
Most carry deoxygenated
blood.
Thin layer of muscle and
elastic fibres in wall.
Large lumen.
The effect of gravity
How do you think gravity might affect
blood in the circulatory system?
1. When there is more gravity than we
are used to?
2. When the astronaut is weightless?