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30 Cards in this Set
- Front
- Back
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how is ATP made?
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by oxidising fuel molecules. rip out hydrogen atoms, turn carbon atoms into carbon dioxide, use the H's.
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what are the two major fuel molecules?
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fatty acids and carbohydrates
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what is the structure of a fatty acid?
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long hydrocarbon chain with a carboxylic acid on the end. we will be looking at chain length 2-26 carbon atoms. (2C length = acetate). contain a lot of hydrogens (very reduced)
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what is the structure of a carbohydrate?
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(CHOH)n ie 'hydrated carbon' with one aldehyde/ketone group (instead of carboxylic acid in fatty acid). also contain a lot of hydrogens (very reduced)
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how are H-'s transported?
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on NAD (most common)
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what is NAD?
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nicotinamide adenine dinucleotide, a hydrogen carrier. it's also an oxidising agent
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what happens after the H's are stripped off the fatty acids/carbs?
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enter the krebs cycle as 2 carbon units of acetate carried around on co-enzyme A (Acetyl CoA), H's carried on NAD to electron transport chain.
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what is the function of the krebs cycle?
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to fully oxidise the carbon atoms going into it. (rip of H's and turn into CO2)
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how many CO2 does the krebs cycle produce?
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2
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how are the H atoms used to make energy?
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reacted with O2 to make water and release energy, try to harness energy as ATP
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where is the electron transport chain?
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inner mitochondrial membrane
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where does the electron transport chain get H-?
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from NADH (carrier of H-), which stripped H's from fatty acids/carbs in krebs cycle
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what happens to the H- in the electron transport chain?
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is passed down the chain to O2, as H-s move down chain protons are pumped from matrix out into cytoplasm. this creates a PROTON GRADIENT
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is the inner mitochondrial membrane permeable to protons?
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no, this helps maintain the pressure of the proton gradient (once H+ pumped out of matrix it can't get back in)
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what happens to NADH after it passes H- to the electron chain?
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regenerated as electron carrier NAD
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are the protons pumped out of the electron transport chain from NADH?
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no, they're from the matrix. the Hs from NADH are made into water
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where is the F0 channel?
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inner mitochondrial membrane
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how does the F0 channel work?
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H+ flow through it under pressure into the mitochondria, causing a protein to rotate which interacts with subunits of the F1-ATPase (spins it) which generates ATP from ADP and phosphate
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what is F1-ATPase?
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a series of 6 proteins that are spun due to Hs coming through the F0 channel which produces ATP from ADP and phosphate
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what happens to ATP once it's been created by F1-ATPase?
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leaves mitochondria, into cytoplasmto do work (turned back into ADP and Pi which come back into mitochondria and complete the cycle)
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where do the Hs entering the F0 channel come from?
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they're the H's pumped out of the matrix by the electron transport chain due to the proton gradient
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what is oxidative phosphorylation?
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generation of ATP using a proton gradient
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how would you describe the relationship between oxidative phosphorylation and the electron transport chain?
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they're coupled (one generally can't occur without the other)
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what determines ATP production (fuel oxidation)?
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the demand for ATP (rate of fuel oxidation is coupled to rate of ATP consumption) (can't burn fuels without doing work)
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what is another name for FoF1ATPase?
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ATPsynthase
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when would H+ not come in through the F0F1ATPase? what would be the consequence of this?
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if ADP isn't available. no ATP can be made
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how many H+s are pumped out of the matrix for one NADH?
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10
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what would happen is there was a really big proton gradient?
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would be harder to pump H+ out of the matrix and electron transport chain would slow down
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what's the most important thing a carrier has to do?
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be able to release it's cargo and be regenerated as an empty carrier so it can collect more cargo
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what happens if a cell does 'no work'?
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no ADP available because ATP is stable and will only break down when forced. therefore F0F1ATPase can't work, no protons come through into matrix so proton gradient stays high, lots of pressure makes it hard for electron transport chain to work, stops working, movement of H- down chain stops, NADH can't get rid of H-, no more NAD so no more fuel oxidation
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