Subtitles section Play video
-
Ever wonder where most of the food you eat every day comes from?
-
Well, about 60% of the food you eat is carbohydrates.
-
As you can probably tell from its name, carbohydrates contain carbon, hydrogen, and oxygen.
-
But where do these atoms originally come from and how do they join together to make delicious foods like fruits and pasta?
-
It actually all starts with the air you are exhaling this very minute, specifically the carbon dioxide molecules.
-
Plants are going to breath in this very same carbon dioxide through pores in their skin, called stomata.
-
Plants drink in water from their roots to get the needed oxygen and hydrogen atoms, and their electrons, in order to build carbohydrates.
-
What is that thing?
-
Well, that's a special plant organelle inside the leaves of plants called a chloroplast.
-
It's green beceause of a special light-absorbing pigment called chlorophyll.
-
Each leaf has about 44,000 cells and every cell can have anywhere between 20 to 100 chloroplasts.
-
That's up to 4,400,000 chloroplasts!
-
By now, you've probably guessed that we're talking about the process of photosynthesis and you might be wondering when the sun is going to make its entrance.
-
Let's go back to that original molecule of water.
-
The plant has to split this molecule of water so it can get electrons from it.
-
But, the plant can't pull that water apart by itself.
-
It needs help from the high-energy rays of the sun.
-
So now that the chloroplast has all the building blocks - carbon, hydrogen, oxygen, and electrons - it can use them to go through the rest of the steps of photosynthesis to transform that original carbon dioxide gas into a simple carbohydrate called glucose, C-6-H-12-O-6.
-
That little glucose molecule then helps to build bigger and better carbohydrates like cellulose.
-
Cellulose is a type of carbohydrate found in plants that our body cannot break down.
-
We call it fiber and we eat it in vegetables like lettuce, broccoli, and celery.
-
Plants use cellulose to keep themselves strong.
-
The plant could also turn that glucose into starch, a large molecule that stores energy for the plant.
-
We love eating starch from plants like potatoes, corn, and rice.
-
So you see, when you eat plants, we're actually benefiting from photosynthesis.
-
The plant makes things like starch, which we eat and then break back down into glucose, the first form the plant made.
-
Then, the mitochondria in our cells, powered by the oxygen we breath, can turn glucose into pure energy molecules called ATP.
-
ATP powers all work done by each and every one of your cells, things like communication, movement, and transport.
-
But why do we have to turn that glucose into ATP?
-
Well, think of it like this.
-
You're excited to start your summer job at the local ice cream stand, but your boss has just told you that she is going to pay you in ice cream cones.
-
What are you going to be able to do with those ice cream cones?
-
Nothing, which is why you kindly asked to be paid in dollars.
-
ATP is just like dollars.
-
It is the currency that all cells of life use while glucose is, well, kind of like ice cream.
-
Even plants have mitochondria in their cells to break down the glucose they make into ATP.
-
So as you can see, humans and plants are intricately connected.
-
The air we breath out is used by plants to make the carbohydrates we enjoy so much.
-
And, in the process, they are releasing the very same oxygen molecules we need to breath in in order that our mitochondria can break down our delicous carbohydrate meal.
