Intro to Glycolysis: Study with Video Lessons, Practice Problems & Examples

Glycolysis is a crucial metabolic pathway in carbohydrate catabolism, occurring after the enzymatic hydrolysis of polysaccharides into glucose. During glycolysis, glucose is oxidized to produce pyruvate, along with high-energy molecules ATP and NADH. The oxidation process involves the reduction of NAD⁺ to NADH, highlighting the importance of these coenzymes in energy production. Following glycolysis, Acetyl CoA is formed, which enters subsequent stages to generate additional ATP, NADH, and FADH₂, essential for cellular respiration.

Intro to Glycolysis Concept 1

Everyone. Let's take a look at the introduction to glycolysis. Here we're going to say that carbohydrates undergo enzymatic hydrolysis in stage 1 catabolism to produce glucose. Remember, our macromolecules of carbohydrates through hydrolysis are broken down into a monosaccharide: glucose. Here we have starch, which is a pretty common polysaccharide.

So it's a long string of carbohydrates connected to each other or glucose molecules connected to each other. Through the utilization of water and an enzyme, we're able to cleave all of these bonds that connect the glucose molecules to each other. As a result, we can make n number of glucose molecules. Now n here could be some type of number, a really large number because glucose is a polysaccharide, but this is what glycolysis is. We are using enzymatic hydrolysis to break down our macromolecule of a carbohydrate into glucose molecules, which represent monosaccharides.

Intro to Glycolysis Concept 2

Alright, guys. So when we say glycolysis, remember that glycolysis is part of stage 2 of carbohydrate catabolism. Remember, in stage 1, we have hydrolysis of our carbohydrates into our glucose monosaccharide molecules. Once we get to glucose, we then go into glycolysis. This is stage 2.

In this process, we're going to say we oxidize. So it oxidizes glucose to yield pyruvate and high-energy molecules, ATP and NADH. So if we take a look here, we have glucose. We undergo glycolysis. We're gonna create NADH and ATP.

Remember, NAD⁺ is what oxidizes my glucose into pyruvate. So here is pyruvate here. As a result of NAD⁺ oxidizing glucose to create pyruvate, it is reduced to NADH. In this process, we also make high-energy ATP. Now, beyond this, we go into Acetyl CoA formation where we make our Acetyl CoA, which would then go into stages 3 and 4, which we know its main function is to produce high-energy molecules in the form of NADH, FADH₂, and of course, ATP.

But for right now, remember, when we say glycolysis, this is just a portion of stage 2 of carbohydrate catabolism.

Intro to Glycolysis Example 1

Everyone, so here it says, which one of the following molecules is not a product of glycolysis? Now remember, in glycolysis, we're oxidizing glucose. Right? So we have glucose here.

We oxidize it to form pyruvate. We oxidize it to form pyruvate by using NAD⁺. So NAD⁺ is oxidizing glucose to change it into pyruvate. NAD⁺ as a consequence of this also is reduced to NADH, and we also make ATP.

So if we look yes. Pyruvate is created because we've oxidized glucose into pyruvate. NAD⁺ is reduced to NADH. ATP is also something that we create as a high energy molecule. Now Acetyl CoA is not part of glycolysis.

After glycolysis is done, then we go into Acetyl CoA formation. That is where Acetyl CoA comes into play, but it is not a product of glycolysis itself. So here the answer would be option D.