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Current time:0:00Total duration:4:59

Video transcript

I made a slight error in the electron transport chain video and I just was I wanted to correct it in this one and it's also an opportunity for me to include a couple a little bit of terminology that I forgot to include in that video so when I described the electron transport chain we remember it's just you have some high-energy electrons in nadh and they get transferred from one molecule to another and as they get transferred they go into lower energy states and they release energy and then the final electron acceptor was oxygen oxygen got reduced right here but if you do if you look at both sides of this equation the mistake was I need two hydrogen's if I have two hydrogen on the right hand side in the water I need two hydrogen's on the left hand side so there should be there should be a two right there so that was what I would consider to be a minor mistake in the last video but this also gives me a chance to introduce you to some more terminology so this whole process we know that this is called oxidation right when one when NADH loses a hydrogen remember oxidation is losing formerly electrons but it loses the hydrogen's it loses the opportunity to hog that hydrogen's electrons so we this whole process of the electron transport chain is one molecule after another getting oxidized until you have a final electron acceptor in water so this is obviously you could call this oxidation you know just very generally and then the second part of the electron transport chain or maybe this we shouldn't even call this part of the electron transport chain the process where the ATP is actually formed the adding of a of a phosphate group to another molecule is called phosphorylation bus or relation phosphorylation so the whole process of creating ATP by through the electron transport chain remember the electron transport chain releases energy that creates this hydrogen grading it pumps the hydrogen's into the outer to the outer compartment and then that gradient that gradient that hide those hydrogen's that want to get back into the matrix essentially go back through this ATP synthase this process of generating ATP this way is called oxidative phosphorylation oxidative oxidative sauce or relation it's a good word to know you might see it on on some standardized tests or on your exams and it's called this because you have an oxidative part each of these each of these molecules get oxidized in the electron transport chain as they lose their hydrogen's or as they lose their electrons that creates a hydrogen gradient and then that through Keamy osmosis allows for phosphorylation so that's another good word to know this the transfer of these hydrogens these kind of going through this membrane selectively this membrane I mean you know this ATP synthase would allow just any molecule to go through it it's allowing these hydrogen protons to go through it this process right here of this hydrogen going through it is called Keamy osmosis Keamy osmosis another good word to know so the entire process called oxidative phosphorylation it don't happen the same time oxidative generates the energy because the energy to push the hydrogen's out and the phosphorylation happens as the hydrogen's experience Keamy osmosis and go back in and turn this little axle and then push the ATP or the ADP and the phosphate groups together and then you can contrast that with substrate substrate phosphorylation since we're since I'm in the mood to introduce you to terminology substrate phosphorylation this is actually what happens in when the ATP is produced directly in glycolysis and the Krebs cycle so this is in glycolysis and the Krebs cycle and this is where you have an enzyme directly helping to prove the ATP without any type of Keamy osmosis or proton gradient so if you imagine if you imagine an enzyme you know some blurb some big protein blurb and let's say it has the ADP if it has the ADP there with its two phosphate groups and then maybe it has another phosphate group that attaches at some other part of the enzyme this enzyme facilitates without any kind of chemiosmosis or oxidation it facilitates probably in conjunction with other other other energy releasing reactions that maybe are occurring at other parts of the on other parts of the enzyme so you know maybe you have a you can imagine a little spark right there and then that twist the that twist that's this entire enzyme this isn't exactly how it might work but it's a good idea and then these two things maybe get pushed together when it's just an enzyme without any of this chemiosmosis is driven by oxidation like we learned in the electron transport chain we call this substrate phosphorylation and then the substrates are just the things that attach to the enzyme and have something performed on them so anyway hopefully you found this little video mildly useful