Photosynthesis is not a single reaction, it is a series of many reactions that occur in two stages. The two stages are for the daytime and nighttime. In the daytime, while the sun is out and there is lots of light, molecules in the thylakoid membrane carry out the first reaction. This reaction is about making energy.
This reaction converts the light energy from your photon box to chemical energy like ATP. It makes ATP and splits the hydrogen and oxygen, from the water molecules. This all happens in photosystem II of the thylakoid compartment. The oxygen is then released through the stomata in your leaves every time you breathe out.
The hydrogen ions and electrons enter an electron transfer chain, in the thylakoid membrane. A hydrogen ion gradient is then formed as the hydrogen ions want to move into the stroma, but cannot diffuse through the lipid bilayer. They have to leave the thylakoid compartment through proteins called ATP synthases. When the hydrogen ions flow through the ATP synthase the protein phosphorylates ADP and as a result ATP forms in the stroma. After electrons move through the first electron transfer chain they are accepted by photosystem I.
These electrons then enter a second transfer chain where the coenzyme NADP+ accepts H+ to form NADPH.
Then the second reactions happen at night when there is no light and you are sleeping. These reactions build sugar from CO2 and H2O in your stroma. They use the NADPH and ATP that your body made while you were out in the sun playing with your friends.
Simply put, you go through the Calvin Cycle this takes CO2 you breathe in and attaches it to the enzyme Rubisco. This creates a 6-carbon substance that splits in two 3-carbon molecules called PGA. Each PGA receives a phosphate group of ATP, hydrogen, and an electron from NADPH. The PGA is converted to PGAL. 12 PGAL form in total. Two PGAL are used to form glucose, which is what keeps you full of energy when you wake up in the morning. Now you may be thinking wait 12-2 is 10 what happens to the other PGAL? Well, they get recycled to make 6 RuBP again and restart the cycle for the next 6CO2.
Wait, photosystem I? But we were just at photosystem II… One comes before two… no two comes before one??? I don’t know I’m confused...
Whatever mom my head hurts... I'm going to ask my teacher if we can have pizza for lunch.
And that is why it is very important you drink your photon juice packets every day!