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Every living thing contains
carbon. Human beings
take in carbon through
carbohydrates, fats, and
proteins in food, and
release it as carbon dioxide
gas when breathing out. It
is also released from dead
matter, sometimes quite
soon, sometimes millions
of years later in fuels like
oil and coal.
All living things
In particular circumstances, carbon forms a hard crystal. What is its name?
Science and technology
Carbon cycle
Green plants take in
the gas carbon dioxide
from the air and use it
to make food, converting
it into things such as
carbohydrates. Animals
take in some of the carbon
when they eat plants.
Animals
breathe
out carbon
dioxide.
Carbon dioxide
in the atmosphere
Animals
Animals such as these sheep
contribute to the carbon cycle
by eating, breathing, and
dropping waste. They take in
carbon in the plants they eat,
and release it when they
breathe out. Their bodies
will release more carbon
when they die.
Animals eat
plants and take
in some carbon.
O
X
Y
G
E
N
C
A
R
B
O
N
D
I
O
X
I
D
E
C
A
R
B
O
N
An animal’s
droppings also
contribute to the
carbon cycle.
C
A
R
B
O
N
D
I
O
X
I
D
E
R
E
L
E
A
S
E
D
