Page 57 - The Manga Guide to Biochemistry

What is the biogeochemical cycle?

The elements of the global ecosystem, including the food chain, respiration, and
photosynthesis, are all part of a worldwide cycle known as the biogeochemical
cycle.

light

photosynthesis Respiration

Eating

Carbon from the starch Carbon used as fuel and

of potatoes (C) raw material for the body

When one organism, like a bear, eats another organism, such as a fish, the
material that made up the fish becomes part of the bear.

A very important substance in this transfer is carbon (C).

Look at the diagram above. If Kumi eats a potato, the carbon from that potato
enters her body.

And when I breathe, the carbon that was inside my body becomes carbon
dioxide (CO2) and is expelled from my body.

That’s right! Then the carbon that left your body is captured by plants through
photosynthesis and is transformed into the carbon that makes up starch (which
is a type of saccharide).

Then that potato is eaten by Kumi (or a cow or some other hungry creature),
and the carbon is returned once more to the body of an animal.

Photosynthesis and Respiration 43