Hi. There s O a lot of this problem you're gonna have to refer your textbook to see there is, um, not the picture, basically of the grap indicating the values that I'll be talking about here. But I thought that it's pretty easy to look at, right. The one that you're looking at is right underneath the problem that says mutation and sequence and mm absence and mm mm present. Um, from that we're gonna move on the let's. Okay, let's start out with, like, basically the set up of the problem. So you're looking for the operation called M M N. It has four sequences A, B, C and D, and it encodes to m sides one and two for this, right? The mutations in this sequence, um, have the effects of, like, a plus sign where that indicates that an enzyme and synthesized and a minus sign indicates which indicates that there is non enzyme synthesized on dso were given to questions. Basically, one of them is asking if it's induce a ble or festival. The operation, I mean and then be asked you to identify the regulator gene, the promoter structural gene for enzyme one and I'm sorry. The structural gene for enzyme to All right. So we're going to go through and talk about some of these, so I'm gonna put over a green dot over basically everything that's important. Um, we're going to start with a So the answer is that M m M is a repressive ble opera on. Um, I like to type things out. You need to pause, go slower. Whatever you need to do, it's totally fine with me. Um, but this way you can kind of have some notes to go on while at the same time, I'm going to further explain vocally, Uh, basically, where there's no mutation. Thean enzymes are synthesized in the absence of Mm mm. Whereas in the presence of mm. In the end, times are not synthesized. We can conclude from that that this operation on can act as a oppressor or co repressive who repress the opera on. So, in absence of mm mm, the operation is active. When? When there's the operation, is there? I mean, where there is? Mm mm. The opera on is repressed. So we know it's a repressive Alaa Peron. Yea, So moving on part B. So this one. There's a little bit more fun, in my opinion, basically trying to fill in the blank. Always a fun part of biology. So it starts out with the regulator gene, which I put as e I know. It's so exciting. In the case of the B mutation, there is, um, Constitutive Expression Constitutive Excuse me. Expression of enzymes one and two. This means that B is a regulatory gene. Okay, A mutation and regulatory gene does not allow the binding of a repress er to bind to that Be jean. This allows for conservative expression and the genes that are transcribed even in the process of eminent. So next up, we have to talk about Promoter de which basically the question was, What's the promoter? And then you put deep. And then if you want to understand why you say in case of de mutation, we see that the end times are not synthesized both in the presence and absence of mm. Remember, M m m is a repressive all opera on. Um, this means that there's a mutation in the promoter. It does not allow the binding of the RNA promoter being deep, by the way, allow the binding of RNA polymerase two promoter and hence there is no transcription of genes even in the absence of nml. So he is really important. Remember that it is the promoter moving on. So it asks you the structural gene for enzyme one. It's a so exciting. In the case of a mutation, we see that the end time to is synthesized and someone is not synthesized in absence of Mm mm. That operation that's irrepressible. This indicates that a code for NZ in one, um in the case for structural gene for the enzyme to it. See which, in case of C mutation, we see that the enzyme oneness synthesized but enzyme to is not synthesized in the absence of feminine. This indicates that c codes for enzyme to So, um, it's important to understand the concepts here, but it worked through some more problems like this. If you're still a little confused, you just want to be able to identify the regulatory gene, the promoter and the structural genes for the enzymes you're working with and whether or not it's repressive ble or an inhibitor. Anyway, um, I hope that, like helps you understand why this is important because this is kind of how we figure out how to design experiments, for one thing, and then just like understanding how enzymes synthesize is very important.