Photosynthesis. Using the sun’s energy green plants convert carbon dioxide and water into simple sugars and oxygen. Along with carbon dioxide, plants also need water, which is gathered by the plant’s roots, to make food through the process of photosynthesis. The stomata allows oxygen to be released through this process. This oxygen is an important exchange for all living things. Plants take in the carbon dioxide and give off the oxygen that we need in order to breathe.

Relsqui, without getting into too much technical detail, which would leave me breathless anyway, which is why I am glad plants do produce oxygen, here is how it works. Perhaps the use of the word 'convert' was too simple. Using the energy from light, the plant cells tear apart the molecules of carbon dioxide and water, CO2 and H2O, ( I don't know how to do subscripts here on the bag, so I hope you understand that). In the second step the plants recombine those seperated Carbon, Oxygen, and Hydrogen atoms into sugar. The thing is that after making the sugar there are some oxygen atoms left over and that oxygen is released . The actual formula is 6(CO2) + 6(H2O) (+ light energy) > C6H12O6 + 6(O2). Photo synthesis takes place in cells called chloroplasts, which contain the chlorophyll, chlorophyll looks green because it reflects green light but absorbs red and blue, it is the red and blue that provides the energy. That's been proven by hundreds of sixth grade science fair contestants who grow plants under differant colored lights. ( as far as I know very few have investigated the effects of colored lights on model volcanoes) You might be interested to know, and even if you're not I'm gonna tell ya anyway, that at night plants actually take in oxygen and give off CO2. That's because they are breaking down that sugar to get energy for growth and combining other elements, minerals, and chemicals for making flowers, fruit, seeds etc. Actually they are doing the same thing in daylight too, but photosynthesis is so efficient that the plant makes more sugar than it actually needs so there is an excess of oxygen. The excess sugar is in the sap and juices of fruit along with water that is not broken up. That's a good deal for us cause we can tap Maple trees for syrup without doin the tree much harm. Eatin pancakes with turpentine ( which comes from pine sap, is just not a part of my healthy breakfast. I don't wanta think about what would happen if I gave the teacher an apple that tasted like a pine cone either. Ty, I down rated your answer cause it was just incorrect. 50-50 vs 90. And cause the question asked about plants and algae are plants. I got down graded cause of my answer about what to do when ya see a endangered animal eating an endangered plant, so I pologize for downgrading you. But even my offensive jokes are based on fact. Thanx,lynne, its a good thing we get these new understanders from time to time to help us figure out how the world works. Its also a good thing that plants just went right along recycling old oxygen without worring how they were doing it. Ewwwwww. the oxygen atoms we are breathing are like a gazillion years old! I mean some of them have been in dinosaur nostrils, yuck. I just read your reply, lynne,( I gotta learn to at least scan the whole thread before I edit) you smooth talker,you. I just go all mushy inside when you talk scientific, I'll ride over on my photosynthetic cycle and you can whisper sweet nothings about protistans, prochlorobacteria, cyanobacteria, chlorophyll a, chlorophyll b (also c, d, and e ), xanthophylls, and carotenoids in my ear. I warn ya, my electrons are liable to get so excited that I'll wanta see your electromagnetic spectrum or even touch your chloroplasts..

People say that we get our oxygen from plants and trees, however it is actually the algae in the ocean that supplies over 95 percent of our oxygen intake. Therefore it is best that we chop down as many trees as possible because they don't help us afterall.

To make the answer a little more specific -- in the first step of normal photosynthesis, which occurs in a system called Photosystem II, a molecule of chlorophyll becomes energized to the point that one of its electrons gets "bounced" into such a high orbit that it is lost, grabbed by the electron acceptor ferredoxin, leaving the chlorophyll with a net positive charge. The chlorophyll then "repairs" itself by grabbing an electron from a molecule of H2O. Because the covalent bonds holding the molecule of H2O together are made by sharing electrons, when one of those electrons goes missing, the hydrogen "loses its grip" on the oxygen. The O2 released from this reaction can then leave the cell. (It doesn't always do so, but that's another story.) If you want a description of the full photosynthetic cycle, or a better explanation, say so in a rating and I'll edit.

The above excellent answer explains the process. An easy way to remember is to recall that plants breathe in carbon dioxide and give off oxygen, and humans do the opposite; breathe oxygen and exhale carbon dioxide. A perfect symbiotic relationship between flora and fauna.. Goldiemae

6CO2 + 12H2O + light energy ---> C6H12O6 + 6O2 + 6H2O In English... 6 carbon dioxide molecules (we breathe out) + 12 water molecules + sunlight produces glucose (their food, sugar) + 6 oxygen molecules (we breathe in) + 6 water molecules

Trees may or may not produce the oxygen that we breath...I was raised thinking that the photosynthesis creates oxygen, but I just came from a forestry center where the speaker said that our oxygen comes from algae in oceans. He did, however, say that our planet's forests cleans the air we breath, and cools the planet by up to 20 degrees per day. So if you cut down all the trees, you will burn in hell! :P

it's called the electron transport chain. That will be my final contribution to humanity