Photosynthesis for Kids
Hey kids. Are you trying to understand what photosynthesis is?
Here, we'll try and help you! It is a somewhat simple process that
accounts for most of the oxygen in our atmosphere, allowing us to be able to
breathe! We wouldn't ever have existed if it weren't for
photosynthesis. We'll explain it here.
Photosynthesis may sound like a big word, but it's actually pretty simple.
You can divide it into two parts: "Photo" is the Greek word for "Light,"
and "synthesis," is the Greek word for "putting together," which explains what
photosynthesis is. It is using light to put things together. You may
have noticed that all animals and humans eat food, but plants don't eat
anything. Photosynthesis is how plants eat. They use this process to
make their own food. Since they don't have to move around to find food,
plants stay in one place, since they can make their food anywhere as long as
they have three things.
The three things are Carbon Dioxide, Water, and Light. You have
probably heard of Carbon dioxide. It is a chemical that is in the air.
Every time you breathe in, you breath in a bunch of chemicals in the air,
including oxygen and carbon dioxide. Carbon dioxide is also one of the
chemicals that causes global warming. But we'll get to that in a little
bit. Here's what photosynthesis looks like:
Carbon Dioxide + Water + Light ----> Sugar +
Plants breathe, just like us. They even have little openings that can
look like mouths, but they are too small for us to see without a microscope.
When we breathe in, we want to breath in oxygen. Plants want to breathe in
Carbon Dioxide. Plants also drink. This is why you need to water
plants or they will die. They use their roots to suck water up into their
bodies, and their little mouths to breath in the carbon dioxide. Once they
have both of these things, all they need is light. Leaves are made up of a
bunch of tiny cells, where this happens. Inside the cells are tiny little
things called chloroplasts. Chloroplasts are what makes leaves green, and
they are also what takes the carbon dioxide, the water, and the light, and turns
them into sugar and oxygen.
The sugar is then used by the plants for food, and the oxygen is breathed out
into the atmosphere. This process as a whole is "photosynthesis."
Things You Need to Know About Photosynthesis
- This happens to EVERY plant, and to some bacteria and algae, too.
Without photosynthesis, plants wouldn't exist.
- Humans and animals do the exact opposite of photosynthesis. They
breathe in oxygen and breathe out carbon dioxide. This means that we give
plants more carbon dioxide, and they give us more oxygen. Without plants
we wouldn't be able to survive, but there is enough carbon dioxide in the
atmosphere that plants would still exist without us!
- Before there was photosynthesis, there wasn't much oxygen in our atmosphere.
So before plants evolved the ability to turn water and carbon dioxide into sugar
and oxygen, there was no way for plants and animals to exist. Before
photosynthesis, bacteria and other living things used other chemicals to make
their food. But when photosynthesis started, it worked really well, so
organisms (living things) that had photosynthesis thrived and evolved into
plants and trees. As more plants grew across the planet, more and more
oxygen went into the atmosphere, meaning that animals were able to start
evolving! We would never have existed without photosynthesis.
- The atmosphere is full of carbon dioxide. Carbon dioxide is a
greenhouse gas, meaning that if it is in the atmosphere, it holds heat close to
the earth, which makes our planet warm. If we didn't have carbon dioxide,
we wouldn't be a warm planet, we would be cold like the moon. If we had
too much carbon dioxide, we would be like Venus, which is a really hot planet.
Plants keep our atmosphere from getting too much carbon dioxide and heating up
by turning a lot of it into oxygen.
What Does This Have to Do With Global
Carbon dioxide isn't a bad thing if there isn't too much of it, it keeps the
earth warm. But when there is a lot of it, our planet warms up. This
is a natural process most of the time. There are a lot of changes in our climate
(climate is weather over a long period of time) over millions of years, but THIS
time, our climate is changing because of US! This doesn't happen much on
our planet. But humans burn a lot of fuel. When your parents drive
their car, it is releasing carbon dioxide into the atmosphere. And when
you turn on your lights, you are using electricity. If that electricity is
powered by coal or other fossil fuels, then that puts carbon dioxide into the
atmosphere too. Have you ever seen a smoke stack at a factory with smoke
going into the air? A lot of that smoke is carbon dioxide!
When just a few cars and factories do this, it doesn't make much of a
difference. But there are almost 7 billion people living on earth, and a
lot of them are driving cars and using factories, so we are putting a lot of
carbon dioxide into the atmosphere, and the plants can't make up for how much
carbon dioxide we are putting out there!
On top of all of this, we're cutting down trees and plants all over the
world, making it even harder for them to replace our carbon dioxide with oxygen!
Even with the amount of carbon dioxide we are putting into the atmosphere, the
world will probably only increase in temperature by about 1 degree, but that is
actually huge! It could melt our icecaps, which could make oceans rise,
and it could cause rivers and lakes to disappear in some places and form in
other places. We don't completely know what could happen, but it could be
That's why you are always helping if you plant a tree or another plant, and
it is why you are helping by not keeping your lights on when you walk out of
your room, and by turning off the TV when you are done with it. Do what
you can to help!