Anaerobic Respiration - Video Tutorials & Practice Problems
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Anaerobic Respiration Concept 1
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Hey, everyone. So in this video, we'll talk about the limitations of anaerobic respiration. Now, you're going to say without oxygen as the final electronic cept the electron transport chain or etc is not able to produce a TP. Now, remember when it comes to stage four of our food metabolism, we're dealing with etc, and oxidative phosphorylation, we're gonna say here that we're dealing with our different complexes 1 to 4 within our etc this portion that's highlighted. Remember N ad positive goes to our complex one to dr well, N A DH drops off its electrons at complex one to become N ad positive. Again, fa DH two takes its electrons to complex two to become F ad again through our chain of these old traveling electrons. 02 is supposed to serve as the final electronic scepter. And with the use of a TP synthese produce a TP. But without oxygen being there, we can't go from etc to oxidated phosphorylation. So what happens instead while pyruvate is redirected through fermentation in the cytosol. So we're not able to go and take the pyruvate and go into the mitochondrial matrix because of the absence of oxygen. So the pyruvate stays within the cytosol in order to do anaerobic respiration. Right. So this is just a quick overview of why exactly is anaerobic respiration happening? Now, on the next video, we'll take a more detailed look at the process of food metabolism, particularly what happens without the presence of oxygen.
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Anaerobic Respiration Concept 2
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So if we take a closer look at our food metabolism, remember here, we're basically having our monosaccharide entering the cy assault. At this point, we should go into glycolysis. And remember in glycolysis, we make high energy molecules in the form of N A DH and A TP. So here in glycolysis, we do create our A TP and we have also the generation of pyruvate. At this point, we should have gone into stage three where we're going from a cytosol into the mitochondrial matrix. But again, we're dealing with anaerobic respiration. So there's no oxygen available. So pyruvate is unable to go towards acetyl coa formation. So instead it continues cycling through fermentation. So here for in fermentation, we have N A DH becoming oxidized into N ad positive to start the whole cycle again. Now, here again, we're gonna say fermentation is the generation of energy in the absence of oxygen. We're still making energy, but it's less efficient than aerobic respiration because we don't have etc and oxidative phosphorylation. Now, here this is utilized by animals and certain micro organisms we're gonna say in the present in the absence of oxygen. So, 02, it's serving as our oxidizing agent fermentation regenerates N ad positive allowing glycolysis to continue. We see that in the cyclic nature of what's going on here because in we're going from glycolysis to pyruvate formation in N A, DH N A DH undergoes fermentation to create N ad positive again and start the whole glycolysis process once again. Now, here we're gonna say recall, glycolysis only makes two A TP. Now, this is much less than the 20 plus A TP. We would have made through aerobic respiration through the etc and oxidative phosphorylation. This is just a way of continue to make energy when conditions are not ideal because of the absence of oxygen, right? So keep that in mind, anaerobic respiration can still make a TP molecules. It just makes way less of them because um our pyro is unable to go into acetyl coa formation and then go from stages 3 to 4 for the creation even more A TP molecules.
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Anaerobic Respiration Example 1
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In this example question, it says why is anaerobic respiration also called fermentation in new Karic cells inefficient? All right. So for the first one, it says, no metabolic processes are able to continue without oxidation. Well, that's not true if there's no oxygen available, that's why fermentation happens. Our pyruvate does not go into the mitochondrial matrix. It stays within the cytosol. So this is not true. Eetc or electron transport chain is not able to produce a TP without oxygen as the final electronic sector. All right. So this one's tricky. The etc doesn't technically make the A TP. It's the oxidated phosphorylation step that makes the A TP. And we're gonna say with O oxygen involved, yes, we won't be able to go through stage four of food metabolism to make a TP. But this thing is not true because it's not the etc, that's even making the A TP. It's oxidative phosphorylation step where it happens. I know we tack on etc and oxidated phosphorylation together. But technically, it's the oxidative phosphorylation step stage complex five where A TP is finally being made through a TP syntax. Now here, glycolysis only produces two A TP molecules per one glucose molecule. This answers better because here it's telling us why it's inefficient. We're only making two a TPATP molecules per one glucose molecule versus the 20 plus A TP molecules we would have made if we had gone through the etc and oxidated phosphorylation stage four of food metabolism. So this is a much better answer. And then overproduction of N AD positive causes glycolysis to shut down. No, the production of N AD positive is what's allowing us to continue with glycolysis. This is saying the opposite. So this is not true. The only answer here that talks about the inefficiency of the absence of oxygen is part C under fermentation. We're only making two A TP molecules versus the 20 plus A TP molecules we could have made if we went through the mitochondrial matrix through stage three and then stage four. So again, C is our final answer.
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Anaerobic Respiration Concept 3
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In this video, we'll take a look at lactate fermentation. Now, here this process occurs in animal muscle cells and it happens during strenuous activity. Now, here we're going to say that pyruvate is going to be reduced by lactate dehydrogenase to lactate. And in this process, one N A DH is oxidized to one N ad positive. Now, if we take a look at this reaction, we have pyruvate and part of it here is going to be reduced. And what we're doing here is we're changing this carbon into an alcohol group. That's where the reduction happens in this process. N A DH is going to be oxidized ND positive. This is a reversible process. That means the enzyme is the same either way we go. I know we're a custom to seeing dehydrogenase as a class of enzymes that we use for oxidation reactions. But because it is a reversible reaction, it can be used for oxidation or reduction. It's a reversible process, right. So here again, we're talking about lactate fermentation. So basically, we're using lactate dehydrogenase to reduce our pyruvate to lactate
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Anaerobic Respiration Concept 4
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In this video, we're gonna take a look at alcohol fermentation. Now, here this process is by certain bacteria and yeast that convert pyruvate to ethanol and carbon dioxide. Now, here pyruvate to ethanol happens by a two step process. Now, in these processes, we're gonna say one carbon atom is lost as carbon dioxide. If we take a look here at the first step, we have pyruvate here, we've highlighted the carboxyl group of pyruvate. We use pyruvate decarboxylase because decarboxylate is occurring. Remember, decarboxylate means that we're losing CO2, losing CO2 creates an aldehyde group and because this is 12 carbons long, this is ethanol. Remember aldehydes and with al in step two, once we've created our ethanol, we're gonna say one N A DH is oxidized to one N ad positive. Here, we'd say that our Ethan now is going to be converted into ethanol, right? So here, if we're looking at this, we're going to say that um our, our aldehyde group is reduced into an alcohol group. So we're creating an alcohol. So we'd say that this is an alcohol dehydrogenase, right? So when it comes to our alcohol fermentation, this is a two step process that we would employ in order to change pyruvate first into ethanol and then from ethanol to ethanol.
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example
Anaerobic Respiration Example 2
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So here it says pyruvate is converted into ethanol and carbon dioxide by which of the following enzymatic reactions. All right. So pyruvate is directly converted to ethanol by alcohol dehydrogenates. Now, this is not true. We know that it is a two step process. So this cannot work. Next. Pyruvate is converted to acetyl aldehyde by pyruvate decarboxylase then reduced to ethanol by alcohol dehydrogenase. All right. So remember we have pyruvate is gonna be changed into ethanol and then from ethanol to ethanol in order to change it into ethanol, we do use pyruvate decarboxylase because it's a decarboxylate reaction, we lose co2 and then ethanol is going to be reduced to ethanol through the use of alcohol dehydrogenates. But here they're using the term aceto aldehyde. Well, remember we're gonna say ethanol here is a two carbon chain. The end carbon is in is an aldehyde. Other, another name for ethanol, it's more common name is acetyl aldehyde be because as a seal here is talking about two carbons with the carbonyl involved. And then aldehyde is talking about that end carbon being aldehyde. So this one was a little bit tricky little um covered up in terms of which is the correct answer. Ethanol is the same thing as a seat of aldehyde. So B is our answer. Now, if we look at the other options here, pyruvate is converted to lactate. No, it's pyd being converted into ethanol, prud is converted to ethanol by oxidative decarboxylate. So remember we do do decarboxylate that change pyruvate into ethanol, but then we have to go one step further and reduce that ethanol into ethanol. OK. So this does not work. So here, the only correct answer is option B.
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Problem
Problem
How is aerobic respiration different from anaerobic respiration?
A
Anaerobic respiration produces ethanol or lactate, while aerobic respiration produces water and more CO2.
B
Fermentation takes place in the mitochondrial matrix, whilst pyruvate oxidation takes place in the cytoplasm of the cell.
C
Aerobic respiration produces less ATP than anaerobic.
D
Aerobic respiration can be described as reduction reactions, while anaerobic is oxidation reactions.
E
Both fermentation and pyruvate oxidation produce NAD+.
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Problem
Problem
Select statement that explainsimportance of conversion of NADH to NAD+ during anaerobic respiration.
A
Cells rely on glycolysis to produce ATP and NAD+ in the absence of oxygen.
B
Conversion of glucose to pyruvate in glycolysis requires NAD+ as an electron acceptor.
C
Allows for conversion of glucose to Acetyl CoA in the absence of oxygen.
D
Regeneration of NAD+ through fermentation ensures that glycolysis will come to a halt.
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Problem
Problem
Circle the correct type of respiration under which:
a) Pyruvate converted to lactate (aerobic or anaerobic)
b) Glucose converted to pyruvate (aerobic or anaerobic)
c) Pyruvate converted to Acetyl CoA (aerobic or anaerobic)
d) Pyruvate converted to ethanol (aerobic or anaerobic)
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