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Main content
Current time:0:00Total duration:4:27
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Video transcript

in this video we're going to talk about what is arguably my favorite enzyme and that is ATP synthase and you might be able to predict from its name what it does it synthesizes ATP now you've probably seen it before we saw it when we looked at respiration or you will see it when you look at respiration which is going on in most of the cells of your body and you also see it when you study photosynthesis the general thing that it does is is it sits across a phospholipid membrane and through other processes you will have hydrogen ion concentration increase on one side of the membrane have a higher idrija hydrogen ion concentration on one side then on the other side you still might have a few over here and a hydrogen ion is essentially a proton on so on the this side of the membrane it'll be more positive so there will be a electro-motive force to go to the other side and also you just have a higher concentration so there's a chemical gradient a concentration gradient where if there's some way for these protons to get to this side they would want to get there so there's an electrochemical gradient that they would want to go down an ATP synthase provides a channel for those protons but as those protons travel through the ATP synthase they turn this part of it which drives this axle and then this axle nudges these parts of the protein so that they jammed together an ADP with a phosphate group to produce ATP so down here you going into this part of the complex you'll have an ADP and a phosphate group and then that rotation force that's provided by that electrochemical gradient that then produces our ATP and that's going to be the case both in respiration which occurs in the mitochondria and in photosynthesis which occur in chloroplasts now there's a few differences in mitochondria the hydrogen ions these protons the concentration builds up in the inter membrane space right over here because of the electron transport chain studied that in other videos and then the protons travel through the ATP synthase you could see a little mini version right over it here you could imagine that what we see really big that is a blown-up version of this part of the mitochondria and this is of course is not to scale so in the case of a mitochondria this would be the inner membrane right over here would be the inter membrane space between the inner and the outer membrane inter membrane space and right over here would be the matrix of the mitochondria and so as the protons go through they're able to produce ATP in the matrix now in chloroplasts the hydrogen protons build up inside the thylakoids which are these parts of the chloroplast that space inside the thylakoids often call the thylakoid space sometimes called the lumen that proton build up inside the thylakoids happens because of the light reactions the first phase of photosynthesis but then those protons will travel through the thylakoid membrane through this area which is known as the stroma in chloroplasts and they produce the ATP in the stroma but then the ATP is used in the second phase of photosynthesis to synthesize carbohydrates which is you could use one of the end products of photosynthesis so the big takeaway of this video is one ATP synthase is incredibly cool if you look up on the internet you can find some simulations that show ATP synthase and how it acts like a motor to jam the phosphate group to the ADP to produce ATP and ATP synthase in mitochondria and chloroplasts are remarkably similar although they sit in different parts of these organelles and they the ATP in mitochondria you can view is the end product of respiration while the ATP produced in chloroplasts is an intermediary store of energy which is then used to synthesize car hydrates
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