Why do chemical reactions in the body require enzymes?

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All right. Hello everyone. So this question is asking us how do enzymes facilitate chemical reactions in the human body? And here we have four different answer choices which we'll discuss later in this video. So just to give a little bit of general context, right, recall first and foremost, that enzymes are specialized proteins that are responsible for catalyzing biological reactions. In other words, the reactions that we need for things like metabolism. So basically because there are so many different reactions that take place in our bodies, many different pathways that require several steps. Enzymes tend to be very specific, not only to their substrate but also to the type of reaction that they catalyze. So that's great. But what is the role of an enzyme? How do they make reactions proceed faster? Well, their role in metabolism has to do with reducing the activation energy or e of a of a given reaction. Think of activation energy as an energy barrier, right? It's the minimum amount of energy that the system needs to have in order for the reaction to proceed forwards. So by reducing the activation energy, that barrier is lowered, which means that the reaction is more likely to to occur, right, to proceed. So with this in mind, let's go ahead and analyze some of these choices. Now, option D simply says none of the above which is not going to be true in this case. So let's start with option A which says that it lowers the speed of a fast chemical reaction so that it cannot ruin some biological processes. This is not true, right? And in fact, as discussed before, enzymes actually do the opposite. What they do is that they make slow reactions occur faster by reducing that energy barrier. So option A is not correct. Option B says that it increases the heat of reaction. Mm So that or so the chemical reaction can go faster. Now, it's worth mentioning that the activation energy shouldn't be confused with delta H or the heat of the reaction. The delta H of a given reaction is inherent to that reaction, right? It's the difference in heat between products and reactants because that's inherent to the starting materials and to the products, enzymes don't actually modify that. So there's just to go ahead and clarify, there is no change in the difference in energy. There's no change in the delta H only in the activation energy. This brings us now to option C which says that it speeds up low speed chemical reactions so that so that it can provide products needed by the cell at a particular time. This is true. Right, as mentioned before, what enzymes do is that they help important reactions proceed faster so that our bodies can use whatever products might result from that reaction. So c is going to be correct here and there you have it. So with that being said, thank you so very much for watching and I hope you found this helpful.

Why do chemical reactions in the body require enzymes?

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Key Concepts

Enzymes

Activation Energy

Metabolism