BLOOD
Blood is a complex and extremely important part of
our body – we could not survive without it. There is no
replacement for blood, and it performs many jobs in our
body. Blood is pumped around your body in your veins
and arteries. This is called the circulatory system and it
helps to take nutrients and oxygen to all of the cells in
your body, and also removes all of the waste. It is a very
special form of transport system that also helps to fight
infections and carry heat around our body.
The average human has around 4-6 litres of blood and it
makes up about 7% of a human's total body weight. Blood
contains several things – red blood cells, white blood cells,
platelets and plasma. Let's learn a bit more about these!
Red blood cells
These blood cells look like flattened
basketballs and most of the cells in
your blood are red blood cells. These
carry oxygen throughout the body
and collect carbon-dioxide and take
it back to the lungs where it can be
breathed out.
There are millions of red blood cells
in one small drop of blood. They are
made all of the time in your bone
marrow inside your bones. They only
live for around 4 months. They are
red because they contain a substance
called haemoglobin which contains
iron and carries the oxygen around.
10 FUSE
red blood cells
white blood cells
platelets
plasma