 Assalamu alaikum. In this lecture we are going to talk about the applications of biology. As we know that any study of science they have a main purpose and that purpose is betterment of the lives of the human beings. Biology also have to serve the same purpose. Biology itself is the study of life, study of all the living organisms present on the planet earth. So the biologists they explore all the living organisms, their environments, their processes, their systems and how they interact with their abiotic factors and how they interact with each other. This make it possible to use the knowledge of biology in different fields of life. Biology help human beings in medicine, in industries, in health related fields, in a wider range of industries, in handling with animals, in handling with environment and environmental problems and so on. We are going to talk about all of these things today. The population of human beings in the world is increasing and it is increasing quite fast. If we talk just about Pakistan, the population of Pakistan increased too much from 1947 till now. We are about 17 crores. As the populations increase, the demands and the problems of people also increase. If we have millions of people, billions of people in the world, millions of people in Pakistan or in any other part of the world, we have to feed them. All of them, they need foods, all of them, they need protection from the environmental hazards and changes, they need shelter, they need education, they need health facilities and their problems also increase. As the populations increase, food or the food crops, we have to increase their supply. As the population increases, the diseases and the health management, its costs also increase. So as the populations increase, their demands increase and their problems increase. To cope with these demands and the problems, biologists are also working hard to help the humankind. Biologists explore the phenomena of nature, find out the problems which human beings are facing and they also find out in the nature the ways by which they can resolve these problems using the biosphere, the biological world. Biologists introduce different types of techniques and technologies which can help human beings in many different ways. Biotechnology for example, is one of those very important applications of biology, which is the industrial use of microorganisms and other organisms in making products. As we know that human beings are culturing animals from centuries for their own purpose for getting proteins, milk and eggs from animals. We also grow crops for getting food, we grow wheat, we grow rice. How biology can help? Biology help us in improvement of the yields of all of these things. Biology helps us in understanding all the mechanisms by which all of these, for example, growth of crops, growth of animals, their feed, the interaction between these animals and plants in the environment, how they work. And in this way we find out different solutions to the problems that come when we are growing these animals or plants or other organisms for our own purposes. For example, the disease control, when we grow our culture, for example, cows, they may sometimes are infected with diseases. When they are infected with diseases, we have to find out the solutions that how we can treat them and how we can prevent these diseases. So biology helps us in so many ways. We are going to talk about various applications of biology one by one, which are the most important ones. Though there are lot many other applications which are present, which are there. Biotechnologies used with the help of living organisms. This term was first used in 1970s for some specific techniques in which the living organisms were used. Biotechnology, if we define it, it is the use and manipulation of biological processes, organisms and systems to manufacture products to improve the quality of human life. That is, when we want to use any organism for making a product, for example, we commonly make cheese, we commonly make yogurt. Many of you may know that yogurt is produced with the help of some bacteria or the yeast. When we actually make yogurt, we add some inoculum to it. That inoculum is actually taken from an older culture, that is, some yogurt, maybe a spoon of yogurt added to a bowl of milk to make it or convert it into yogurt. That old yogurt actually has some microorganisms in it, maybe bacteria, maybe yeast, maybe a combination of more than one bacteria and they convert that milk into yogurt. We can use the natural properties of organisms to make products. But we also can modify their properties, we call it manipulation. We can manipulate the present properties of different organisms, particularly the microorganisms like bacteria or yeast or viruses to convert them into those forms or we can change some of their products into our own products of interest. As we know that all of the microorganisms, they have genetic material in the form of DNA and with the help of techniques of molecular biology these days, that is, the biology of molecules. We know that molecules include proteins, nucleic acids, lipids, carbohydrates, all of the, we are of course talking about the living molecules, the biomolecules. These molecules could be modified, particularly the genetic material, the DNA. We can modify some parts of DNA, we can remove some unwanted genes from an organism, we can add a required gene to the genome of the organism. Here I just mentioned that genome is the complete set of genes present in an organism in the form of DNA. When we modify the genome, we manipulate the genome or any of the genes of an organism, we do it by a process called genetic engineering. Genetic engineering, genetic of genes, engineering, changing or modifying by using different techniques. It means that we can change some part of the genes of an organism. We do it mostly with the microorganisms. Why microorganisms? Why we select microorganisms for this purpose? The thing is this that growing microorganisms is easier in comparison to growing all other larger organisms. For example, if we are going to grow buffaloes or cows, we need a large space, we need much more people, we need much more resources. If we are growing same number or actually very large number of bacteria in comparison to the cows, we actually need much less resources. Microorganisms grows very fast. We can get many of their generations in a very short period of time. The microorganisms become extremely useful for all the genetic engineering, fermentations and most of the industrial processes that uses living organism, the biotechnology and the genetic engineering. If we define genetic engineering in broader terms, then it is a process in which a useful gene is taken from one organism and it is entered in another organism. The organism which is produced by addition of this useful gene is called a transgenic organism. Sometimes it is also done that a gene of interest is removed, that is a gene on purpose is removed from the genome of an organism to convert it into a model for maybe for example some diseases. This is also genetic engineering. For genetic engineering mostly we use microorganisms, sometimes we use animals and plants as well. We genetically engineer certain plants, we genetically engineer certain animals and what is our purpose? For example, we can add a gene of resistance into the plants, we know they are exposed to different types of diseases. Once particularly when we are talking about our crops which are useful for us and we grow them on our purpose, the cash crops, they are not resistant to certain viruses. If we add a gene for resistance to that particular virus which can attack that plant, mostly these genes are found in bacteria. So we can remove that resistance gene from bacteria and insert it into plants and those plants will also become virus resistant just like those bacteria. Just like that we can sometimes genetically engineer animals. The process of genetic engineering is carried out with the help of vectors and enzymes. How we carry out this process? We need a vector. When we want to transfer a gene from one organism to another organism or from one part of say an organism to another, we need vector. Mostly for the transfer of gene we use a specific vector called plasmid. We know that bacteria, they have two types of DNA, the genetic material. One in the form of a single circular chromosome and the other which is a single circular DNA molecule called plasmid. Plasmid is the most important vector used in the genetic engineering and in biology techniques. The other thing we need is an enzyme, actually not one, many more, lot many enzymes. There are specific because when we have to cut a particular gene from an organism's genome and we have to insert that gene in another organism's genome, we need to cut the DNA. And to cut the DNA we need enzymes because we do not have any other scissors to cut down those molecules of DNA, they are too small. But in nature in those the same cells there are certain types of enzymes which naturally break down the DNA. These enzymes are present in bacteria and these are a natural help for those bacteria because these cut down the DNA of any organism which is attacking that bacteria. For example a virus, these enzymes cut down the DNA of the attacking organism. So the host is saved. Most important of these enzymes are called the restriction enzymes or more precisely restriction endonucleosis. These cut the DNA with sticky ends. Sticky end means that when they cut the DNA, they cut it in this way that another part of DNA can come and attach to this DNA molecule, most probably a plasmid or sometime some other part of DNA. So most common enzymes are the restriction enzymes or the restriction endonucleosis. Let us have a look on this diagram. The diagram shows you the process of genetic engineering in a very brief way. An insulin is very important molecule. We know a name of a disease called type 1 diabetes mellitus. The people with type 1 diabetes mellitus have to use insulin because their body cannot produce insulin. We have to give insulin to them externally in the form of injection or some other form. This insulin was initially produced in the pigs or in the buffalos, the bovine insulin and the porcine insulin. But the problems were there because number one, these were very costly and number two, these may cause some allergic reactions because this was not human insulin but this was bovine or porcine. So the scientists, the biologists, they solved this problem with the help of biotechnology. See how they have done it. Here you can see a beta cell of human pancreas. The insulin gene from the beta cell of human pancreas cut it with the restriction enzymes and they took bacterial cells, very common bacteria and very safer bacteria to use, E. coli or deskracea coli. They removed plasmid from the E. coli and they also cut plasmid of the E. coli with the same restriction enzymes with which they cut the insulin gene. Then with the help of another enzyme called ligase, they attached or we can say they added the human insulin gene into the plasmid. Now the plasmid is genetically engineered, we call this a vector. This plasmid was inserted into another E. coli. Now this plasmid is genetically engineered and this E. coli is also genetically engineered because it have a modified genome. This plasmid is modified with the help of biotechnology. So then this genetically engineered E. coli, this was grown in mass cultures and because it have a human insulin gene, it can produce the human protein insulin and growing E. coli is much cheaper in comparison to growing the cows, buffaloes or the pigs and second important thing that this is because this insulin molecule is a product of human gene inserted in the plasmid. So this is exactly the human insulin, there are no allergic reactions. So what happened? The cost of insulin was decreased. Actually it became accessible to the poor people even and all of the people and secondly there were no allergic reactions because it was produced by the human insulin gene inserted in the E. coli. So and just like that, just like the same process, human growth hormone is produced for the dwarf children. In some children their growth is stopped because of their human growth hormone production is reduced, they for these children human growth hormone was produced by just process like this genetic engineering and their growth was normalized. Just like that lot many other products for example interferons for the treatment of hepatitis and cancer, they are also produced with the help of genetic engineering. So this is a extremely useful technology with the help of which we can produce lot many useful products for human beings. With the help of genetic engineering we make organisms, bacteria, sometimes plants, sometimes animals. The organism which is produced with the help of genetic engineering is called a transgenic organism. We have transgenic bacteria, we can have transgenic animals, we can have transgenic plants. Transgenic modified with the help of genetic engineering.