And then we want to know how. So this is really the hot wires that come in. So you have all these structures being built up. Now there must be a program that runs it and I think in the modern day, we say that, well, there must be a genetic program. So we all learn about that. If you have any kind of science class, you learn about that. We are made of this nucleotide called GATC, then somehow they embed into it with a lot of information. So what is it? It's that this is a genetic material we have, they go for a process which we call transcription and translation, so that it can make into RNA and protein. What is it? Essentially, they carry information. So you can look at it, it's that every single piece of DNA is some functional unit that carry information. So I can call that as a memory unit, it carry the information. And if you want to look at it in the other way, are there engineers here? Yes, then you'll see that the engineer will seem to say that, "Oh, all this DNA, they're simply a piece of nuts and bolts." You can assemble them in any way, and they carry information. You can shuffle them and reassemble them so that they still create a big piece of DNA so they carry information, so that you'll be able to use it to direct some biological function to make things happen. Now again, that is very degrading because what it means is that, everything is already in the DNA. Whoever you are, everything is built in. So therefore, we say that, well, is life solely defined by our genetic material? And this genetic material, we can call it DNA. And so if we can understand all the DNA sequence, what they are encoding for, and what is in that, so basically I can define actually what you're going to be. Deterministic, essentially it's talking about how things are being determined in such a way, and it's with such a deterministic program. So what's our identity? What are you going to become? So basically, I can say that when you're born, I pretty much know what you're going to be in the future. Is that the case? I would say most of you would not say yes, okay? Because all along your experience that you are going through a process that you seem to accumulate something, and you become slightly different over time. Now so that essentially is the point. So the question I'm asking is that, are we who we were when we were born? Are we? Are we not? Now, this is the question you need to think about. So another way to look at it in a very degrading way. As I pointed out, DNA seems to be governing all the process that eventually how things happen. So then, who are you? If you're a guy, what wanted you is that you want to get married, and then you pass your DNA onto your next generation. So if you know that DNA probably govern everything in the process, then essentially you become a vehicle where this DNA hijack your body, to make some sperm from you, and get transmitted to the next generation with more DNA, so you become a vehicle. It's an entity of DNA taking the form of a human being, and transform it into more DNA into next-generation. And all the living organisms will be the same. You have a bacteria. They go through a process, they make more DNA, and they split and they become two cells, and then you make more DNA. And you keep on going and keep on going, then you make more and more DNA. So we are just a vehicle being utilized by this DNA program. Are we functioning in that way? If you think about in the future world, what is it? So if that's the case, let me tell you. In fact, we are part of that process. But in that process, there is a very important component which we need to remember, which is, hey, DNA need to make more DNA, but then in order to make sure that all the DNA are made properly, you need to inject a lot of effort, energy, a lot of enzymes, component, machinery to make sure that your DNA is replicated properly. But do we make mistakes? We do. And the mistake we make is, roughly I think one mistake per 100 million or one in a billion. Now, so think about it. What does that mean? One in a billion or one in 100 million. How big is our genome? Our genome is about three billion but you make one mistakes per billion. So what it means is that, if your DNA gets replicated once, you make three mistakes. Hey, it's pretty bad, alright? Is it good or bad? In some organisms, actually they can go even higher, right? So but then what I want to argue with you is that, making mistake is okay. Now, for all the PG students here, UG students here, this is the take-home message, making mistake is okay. And in fact, if you don't make mistake, you have a problem. I'm telling you later, alright. And when you make mistake, provided the mistake is not happening every day and every time you do it, that's okay. So that mistake becomes the major driving force for us. What exactly is it? Because of this mistake, over the million and millions of years, organisms evolve in one way or the other. So that means for one cell to become two cells, they make some mistake. From one generation to another generation, they make some mistakes. When the mistakes were made, so what happened is that, you and I become very different. Of course, you are female, I'm male, right? So but, you and I both are male, but we still don't share identical DNA, because long long time ago in our ancestor, we start making mistake so that, you and me become different. And in a way, we generate all this diversity. This picture is taken out from a study showing that, actually what's the color tone. So these are all human beings with different color tone, and they can differentiate that into hundreds of different kind of tone of the skin. So what happened is that, well, it's because the minor adjustments they make. One mutation, one mistake here, and one mistake over there, they all become different. And so that's how we generate the diversity that we have today. And diversity is a very important part of it. Now, let me come to a very interesting part for you to think about. I want to use this as an example to illustrate. So this is a black cottonwood. This is the kind of plant which is growing over a period of a few hundred years. They can grow from a single seedling and all the way to have a few 100 feet in height. And so what is it? You can easily think about, when they grow to be so tall and so thick, if you trace this tree and go down to the root, that root was originally from the seedling, which was laid down there two, three hundred years ago. And it keep on dividing and dividing and they made mistakes. So when they continue to divide, that means all the progeny of the cells from the original seedling, they become different. And when they grow all the way to here, they may have leaves which was just born yesterday. So that means, if you go from the root to where the leaves is, they are separated by 200-300 years in terms of the age. So in the process, they are thousands and thousands of cell division. So how different are they? So it's crazy, scientists would do experiment, they tried to look at, "Hey, if I pick some DNA from this cell, and I pick some DNA from the other, do they look the same?" The answer is, no. They don't look the same. In fact, they've identified there are 188,000 mutations accumulated along the path so that they generate, wow, 5,000 amino acids in different proteins got changed. So essentially, they are almost like two different species, but it is one single plant from the root to the leaves tip. Alright. So if that's the case, then we need to ask yourself, hey actually what is this plant? Can we define this plant as a single individual? Or is it this plant is some sort of a mosaic? Interestingly, let me give you an example, I use myself. This is my index finger, right index finger, and this is my left index finger. How far are they apart from each other? Five feet? But they were born long long time ago, 50 years ago. They got separated. And each of them, as a single cell, accumulated all the mutations. This cell accumulated all the mutation to become this. So therefore, this finger and this finger, actually, they belong to me, but actually they are very different, alien to me. And they would be very different from the cells in my brain. So where am I? So in fact, people even look into it and show that, even within your brain, originally, it's a very small clump of cells. When they keep on growing, they start accumulating mutations, so that the left brain and the right brain in fact, they accumulate different kind of mutation. They become very different. So what it is is that, we are constantly, we are a mosaic. We are mosaic organisms with a mixture of genetic material. So when I ask whether the genetic material determined what you are, are they determining what you are? Not really, because you don't know actually what kind of mistake that each of the cells would make. And it's the combination of all these mistakes combined together that make the collective whole, where you are.
