Photosynthesis

        Has anyone ever wondered how plants are able to "eat" food, and grow like us humans do? Have you ever wondered where the oxygen we breathe comes from? Well, it's actually pretty simple! It's a process called photosynthesis. You're probably thinking, what in the world is photosynthesis? Well I'll tell you! Most life on earth actually depends on photosynthesis. Plants, algae, and some types of bacteria all use photosynthesis. Basically, the plants, algae, etc. all create sugar and oxygen from carbon dioxide, water, and sunlight. Carbon dioxide, light, water goes in. Glucose, water and oxygen come out. Basically, how we live all depends on photosynthesis. Because if we didn't have photosynthesis, then we wouldn't have plants. And if we didn't have plants then we wouldn't have herbivores (animals that only eat plants), and if we didn't have herbivores then we wouldn't have food for us to eat. Not only that, but it provides the oxygen that we breathe. So, when you take a breath or eat, thank a plant. So, as you can see photosynthesis is actually very important for not only the energy cycle, but the food cycle in general and how we get food and air. 

        Okay, so now that you know the basics we can dig deeper on how the process actually works. Photosynthesis can be split up into two different parts. The "photo" part is referring to the reactions triggered by light. This occurs in the thylakoid membrane part of the chloroplast. What happened in this is, the chlorophyll absorbs energy from the sunlight and then takes it and makes it into chemical energy known as ATP and NADPH molecules with the use of water. I bet you were wondering what the water is for, and now you know! 

        Then, the "synthesis" part is referring to the making of sugar. This happens through the Calvin cycle. Now, the Calvin cycle is literally just the name of the process of how the sugar is made. That process is, carbon atoms from CO2 are mixed into organic molecules, and then are used to make three-carbon sugars. See, it's more simple than it sounds! This also takes place in the chloroplast, but instead it is in the Stroma. Now you know the process and what happens a little more in depth.

         Now I'd like to talk about the chlorophyll and the chloroplast. I mean I've mentioned it multiple times in the text, so if I was you I'd be wondering what it is. So, inside every plant cell are small organelles called chloroplast. Inside this is everything I just explained and it also stores the energy of sunlight. In the thylakoid membranes, which I mentioned before when talking about the making of oxygen, contains the light-absorbing green pigment called chlorophyll. The light travels as electromagnetic waves. Some of the wavelength from those waves determine the color we see. Which obviously for plants is shows green, it actually shows this because as the plant goes through photosynthesis the chlorophyll absorb red and blue light, and this mixed together makes the plant reflect green. We see what the wavelength is reflecting. Because every time you think of a plant, most of the time you'd be thinking of the color green. That's how the color came to be.

        I know that may have seemed to be a lot, but it is actually pretty simple. Anyways, I hope you learned something about photosynthesis. It's actually interesting learning things like why plants are green to how the air we breathe is created.

References:

​​N.A. Campbell, J.B. Reese and L.G. Mitchell.(1999) Biology, 5th Edition. Benjamin-Cummings Publication Co.

Weaire, P.J. (1994) ‘Biochemistry Across the School Curriculum’ (BASC) booklet: Photosynthesis.

Tyson Brown (2024) National Geographic society