Intro to Glycolysis - Video Tutorials & Practice Problems
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concept
Intro to Glycolysis Concept 1
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Now, in our journey to understand food metabolism, we can say that glycolysis is part of stage two of carbohydrate metabolism. And we're going to say that it oxidizes glucose to yield pyruvate and high energy molecules. In this case, we're talking about A TP and N A DH. If we take a look here, remember we have stage one, which is basically the breaking down of our proteins, carbohydrates and lipids through digestion into their amino acid, monosaccharide and fatty acids. Here, we're looking at the monosaccharide portion. We're gonna say here that it takes place in the cytosol. This is the portion that is outside of the mitochondria and therefore does not require oxygen. If we take a look here, we have our monosaccharide, we grade out the amino acids and the fatty acids because we'll talk about those later on. For now, let's just focus on our monosaccharide here. They enter glycolysis and in the process, we're gonna create our high energy molecules in the form of N A DH and A TP N ad positive is what we have initially before it gains its electrons. New glycolysis, we have our monosaccharide getting oxidized to create our pyruvate. We have two pyros that are being created with this pyruvate. We've highlighted this portion, this acetyl group portion, which is gonna further go into a keto coa formation. Now, this part of it that we create can either go through the ferment fermentation route, which is under anaerobic respiration, the absence of oxygen or it can go in the aerobic respiration route where it does need oxygen. And from there we go into stages three and four, which takes place within the mitochondrial matrix. Now, remember this is what we've learned so far in terms of food metabolism with stages three, dealing with the creb cycle or the citric acid cycle and then going into stage four, which deals with etc and oxidative phosphorylation in the formation of a TP molecules, right. So just keep in mind that we're talking about carbohydrate metabolism. We're taking a look at stage two and specifically glycolysis.
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example
Intro to Glycolysis Example 1
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Which one of the following molecules is not a product of glycolysis. I remember with glycolysis, we have our monosaccharide that go into it. And with it, we have N ad positive gaining electrons to become N A DH. So N A DH is a product of glycolysis. In addition to this, we also have the formation of another high energy molecule in the form of A TP, we also have the oxidation of our glucose which helps to form pyruvate. So pyruvate is yet another thing that's created through glycolysis. What's not created is a CTO coe acetylate happens later on in stage three. But remember, glycolysis represents stage two of our carbohydrate metabolism. So here answer D would be our answer. This is not a product of glycolysis.
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concept
Intro to Glycolysis Concept 2
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1m
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In this video, we're gonna take a look at the phases of glycolysis. Now, firstly, we're gonna say that glycolysis is a linear catic pathway that consists of two phases. Now, here we're gonna say phase A is our energy consuming phase. Here we have phosphorylation and bond cleavage reaction that split a glucose molecule. Remember a glucose molecule has in it six carbons. Now, here it's gonna produce two molecules of glyceraldehyde three phosphate which will abbreviate as G three P because it's energy consuming, it has to consume a high energy molecule in the form of A TP. So here we have our glucose which is our six carbons. A TP is invested into this process. It's an energy consuming one doing that helps us to split our glucose into two glyceraldehyde three phosphates. Now, in the energy producing phase, we're going to say that we have oxidation and D phosphorylation. It converts our Glycerol three phosphate to pyruvate. Remember oxidation reactions here will produce N A DH and A TP. So this is the energy producing phase of glycolysis. So here we have our two glyceraldehyde three phosphates in the process of oxidation, we're gonna create an A DH A TP. And as a result, our glyceraldehyde three phosphate is converted into two pyruvate molecules. All right. So just think of glycolysis broken down into these two simple phases at this point.
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example
Intro to Glycolysis Example 2
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1m
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Which of the following statements is incorrect. About glycolysis. Glycolysis produces pyruvate N A DH NATP. Yes, this is true. These are our three major products of glycolysis. So this is true. The first phase of glycolysis does not produce any energy. That is also true. Phase A is the energy consuming phase of glycolysis. Phase B of glycolysis produces two molecules of glyceraldehyde. Here, this is false. This is incorrect because phase B creates two molecules of pyruvate by converting two molecules of glyceraldehyde three phosphate. So this is what's incorrect. Now, here, glycolysis produces more energy than it consumes. That is also true. Yes, it takes energy to go through phase A but it's OK because the payout from phase B will be larger, we make more energy at the end than we've consumed in the beginning. So here option D is correct. So here, the only statement that is incorrect would have to be choice C
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Problem
Problem
Which one of the following molecules is a source of energy in the energy-consuming phase of glycolysis?
A
NADH
B
FADH2
C
ATP
D
Acetyl CoA
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Problem
Problem
How many carbon atoms are lost when one glucose molecule undergoes glycolysis?
A
0
B
2
C
1
D
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