Mendel's Life History - Malayalam ｜ Genetics 6th Semester Botany ｜ Cu ｜ Mg ｜ KU ｜ NEET Biology

Welcome all, our today's topic or we are going to start today is a section called genetics. Many of you may have gone to genetics right now. It's very difficult, isn't it? But it's not like that, it's not difficult, it's very easy. You have drawn boxes like this F1 generation, F2 generation, F3 generation, haven't you studied? So that's what we're studying since the 10th grade, isn't it? To write like that. If you understand the technique in what you have written, it will not seem easy to write those boxes. In fact, it seems a little tough in genetics to write those boxes. It's very tough, but you don't have to study it, okay? You just have to learn very simple things. So what is genetics? In fact, it's a study about us, isn't it? Why is it a study about us? Each of our characters, each of our things are determined and coded in our DNA, right? Or to be more specific, it's in our genes. So what is the study about those genes? This is called genetics. Now, the father of genetics is not a biologist, but a mathematician. Gregor John Mendel. You may have heard about him. As we started in the 10th grade, we can learn his name in the 10th grade. Gregor John Mendel is the father of genetics. You can ask for one word, remember. Now, if you want the year of birth and the year of death, if you are taking part in any competitive exam, there is a chance to ask that too. Okay, he was born in 1822 and died in 1884. Okay, remember that too. Now, Gregor John Mendel is the father of genetics, right? But his work in India, for 6 years, when I looked at the data, it was in different ways. 6, 7, 8, I saw from these many years. More specifically, I saw more in the year 6. That is, for 6 years, he conducted studies in Pisum Satevam. He conducted studies and collected data. Pisum Satevam was done in our Pairi, in Garden P. He studied for 6 years, 7 years, 8 years, I saw. But more accurately, I saw more in the year 6. You can look at it again. Okay, so he completed his work in so many years. So, we know that in so many years, he must have done a good data collection. But when he published his work, he did not get any value for it. Because the first reason is that he was a mathematician. Because it is the 18th century. At that time, biologists must have thought, that we do not know that he is a mathematician. That is why, he did not get much attention in his studies. Not only that, at that time, Darwin's theory of evolution, you know that, that theory of evolution was in its infancy. After that, everyone's work was to see if it was right. That is why, he did not get much attention in this area. That is one reason. At that time, after his death, after his death, after the death of Grigor John Mendel, his work was known to the world. He did not get much attention after his death. He died after 16 years. So, why did he not get much attention when he was alive? You can ask. You can ask in the 5 marks portion. Why did he not come at that time? Or, why was he not a lucky scientist? That is how, Grigor John Mendel was known. Now, he said in the form of factors. That is, from one generation to another generation, each information, information accumulating from generation to generation, is passing from one to another. That passing is called factors, that is what Mendel said. At that time, he did not know what these factors were. Now, we call these factors as genes. At that time, there was no microscope to find out what a cell is. That is why, there is no way to know about the genes in chromosomes. That is also one reason. That is the reason why he did not get much attention at that time. Now, if a person is conducting a study and publishing a work, if everyone knows about that work, it should be published in international journals, right? It should be published as everyone knows. But, he published in a local journal. That is, only a few people in a local area knew about it. At that time, in those days, people like us could not understand what a big data is. So, that is also a problem. Now, when did he die? After 14 years, in the early 1900s, his work came out to the world. The world knew about it. The reason why people knew about it was, it was such an important thing. It was such an important area. It was understood by him. Three scientists were part of the work. Because, we know, if we are going to publish something in a journal, or if we are going to publish a paper, you must have done a project in your final year, right? So, when you are doing a project, is it a subject that you have done? Who has done studies in that area? Who has published the work? What was it about? What was it about in the previous period? You have to find out about this subject, and analyze the rest of the things. You know that, right? They may be people who have already done a project. So, like this, these three people, like Hugo de Varys, Carl Conant, and Eric, when they look at the work, they look at the previous period, and see if there were any studies done. In their hands, they get a publication published in the Grigor journal. They get a publication published in the Grigor journal. That's when, in a very accurate way, with a lot of tables and things, in a very accurate way, they do such a big study. But, they don't get the attention they need. That's how it is. Then, in the 19th century, everyone started getting ideas about what a cell is and what a chromosome is. everyone started getting ideas about what a cell is and what a chromosome is. So, more and more, the work of this period got its importance. Now, take the names of these three people, like Hugo de Varys, Carl Conant, and Eric Vaughan. Then, in the 19th century, 16 years later, he died, and 16 years later, they got the publicity they needed. So, these are the things we can learn from this. Now, why did they select the pea plant? or why did they select the beans? the question is asked. The main reason is the short lifespan. In a very short period of time, i.e., 3 to 4 weeks, a bean, its germination, its maturation, and its seed production, completes the life cycle. So, in a year, there are so many weeks. So, if you study for 6 years, every year, 9 or at least 6 generations would have got the beans, right? So, every year, 6 generations, 6 years, how many beans can we get from a single bean plant? So, the lifespan is a very important thing. So, instead of this, if they had used coconut or other flour to study, how many years would it have taken? So, the lifespan was a big reason for the success. Now, another thing is that, in this Peas and Vegetables, there is self-fertilization as well as cross-fertilization. Self-fertilization means, for the same plant, there are two different plants, one A plant and one B plant. What happens between them? Fertilization happens. So, he did cross-fertilization using a paintbrush, a small paintbrush. With that, he took the pollen grains and placed them in the stigma of the next flower. Okay, Mr. Parnoni saw it when he read it. So, self and cross-fertilization happens. That is one reason. Now, we will not show the seed dormancy. We had studied some techniques to remove the dormancy of the seed. What is dormancy? Some plants, when the seed is produced, it will be in an unfavorable condition. Now, it will be in a favorable condition. It is ready to germinate. Until then, there will be a time gap between unfavorable and favorable. There will be a lag. That lag is the dormancy period. But, if the seed is produced today, it will germinate and grow. So, there is no dormancy. Then, as we said, we get a lot of offsprings from a single seed. We get a lot of next generation. That is a big thing. Because, we get a lot of samples from a single seed. So, the size of the sample is more. As the sample size increases, the data will be more accurate. So, when we are testing the coronavirus vaccine, if we test it in 10 people and get 90% success rate, or if we test it in 10 crore people and get 99% or 98% success rate, we can believe that it is done in 10 lakh people. Because, it is done in a way that there is no problem for more people. Similarly, here also, we get a lot of samples What is that? That is also one of the reasons to select this seed plant. Now, contrasting characters. He took 7 contrasting characters. One of them is height. Height is a character. Height has two faces. One is tall and the other is dwarf. Either the height is good or the height is bad. A medium-sized seed plant or an extra-large seed plant will not have such characteristics. If we have a character, it has two different faces. It has two sides. The height is tall and the dwarf is small. The color of the flower is white and purple. That is a contrasting character. No other character comes in between. The height is different. The color of the flower is If it's white, it's white. That's it. Okay, those are the contrasting characters. Now, it's very important to learn about the characters. What are those 7 characters? What are the dominant and recessive characters? Even if it's theoretical, even if it's practical, it will come. At that time, we don't say which one is dominant and which one is recessive. We should remember that. Some people might have seen that in some exam. I had asked them to write 7 characters. What are they? Let's learn. Let's look at the height. Okay, height is a character. Its dominant is tall. Its recessive is short or dork. Now, the position of the flower. The position of the flower is axillary and terminal. Axillary is dominant and recessive is terminal. The color of the flower is purple is dominant and white is recessive. The shape of the stem, the shape of the stem is inflated. Inflated is like this. Constricted is like this. We can know the position of each plant. Okay, this is constricted. There are two such shapes. The color of the pod is green is dominant and yellow is recessive. The shape of the seed is round is dominant and wrinkled is recessive. The color of the seed is yellow is dominant and green is recessive. Okay, whatever it is, learn it. Learn any character. Learn its dominant and recessive character. Anyway, you should know it. When we move forward, you should know it. Now, the reason why our mental studies is so successful in the 18th century. What are the reasons for its success? What are the reasons for its success? First, the selection of contrasting characters. The selection of the seven characters is not shown by the linkage. The height of a character is determined only by the height. There were special genes that determined only the height. It was never connected to the color of the flower or to the color of the pod or to the shape of the pod. It was not linked. That is the point. The selection of contrasting characters is important. We get a lot of samples from a single plant. We get a lot of samples. We get a large data. Not only that, the data is correct. As I said, the data is correctly analyzed and double by double. So the data is successful. If you grow a plant for a month and write nothing about it, write next month and it does not work, you get a correct data and write it correctly. We get a data We are not showing the linkage character The height is not linked to the height of the genes that determine the character Not only the height, the rest is the same In humans, 10-12 genes are combined to determine a single character It is a full mixing, everything is linked So there were no such issues There were no contrasting characters selected in the p-plant If there was a linked character selected by him, we would not have got such an accurate result Because after him, many people conducted such studies in other plants But none of them succeeded So this is it Every point we discussed in today's class is very important I did not ask anything to the essay, but I will ask the essay of 5 months You can ask one by one As we said, you should study without looking at the dominance and recessive of any character