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Intro to life processes

Let's explore the various life processes that keep us alive. Created by Mahesh Shenoy.

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Video transcript

- [Instructor] In order for living things like you, me and this plant to stay alive, to keep living, we need to keep on carrying out certain processes on a regular basis. These processes that we need to keep doing to stay alive, we give a name to them, we call them life processes. And so in this video, we will learn what are the major life processes that all living things need to carry out to stay alive. So let's start with the example of human beings. Let's say me. What do you think I need to do to stay alive? Well, one of the first things that come to my mind is I need to keep eating my food, but why? What's inside food? Well, whether I'm eating my favorite sandwich or not so favorite vegetables, all food contains sources of energy. Think of these white dots as energy sources, okay? These are the carbohydrates, which we usually call carbs. Since they have energy in them, they act as fuel for us. This is very similar to how to make a car run, we need to put petrol inside them. Petrol has energy. It acts like the fuel for the cars. Similarly, the carbohydrates, they act as fuel for us. So our food gives us the required fuel. But not just that, it also contains certain raw materials needed for our body to grow and to build muscles. I mean, when I was very small, when I was born, I was pretty small and skinny, but now look at me, I am all grown up and muscular. Where did all that stuff come from? It came from the raw materials that I got by eating food for so many years. So food use me, raw materials and my fuel. Okay? Carbohydrates. Let me just call it as fuel for now. And so after eating that food and swallowing it, my digestive system is able to extract all the necessary fuel and the raw materials needed for my body. So this is a very important process, I need to keep eating. And so we can say in general, one of the important processes is to get fuel or energy source, and the raw material needed for my body. That I have to keep doing to stay alive. Okay, what else do I need to do? Well, most of the stuff that I've eaten gets only absorbed by the intestine of my body. But what about the rest of the parts of my body? They also need the fuel and raw material. My hands need them, my legs need them. How will they get all the stuff that I have just acquired? Whew, I need to distribute all that stuff to the different parts of the body, right? So that's another major life processes. So I have to distribute them so that all the parts of my body can absorb the raw material and use it to build my muscles and help me grow. And so another important process for me, is I should be able to distribute the stuff that I've just acquired. If I'm not able to do that, most of the cells in my body will die and I will not be able to stay alive. Okay, what else? Now after distributing, each cell of my body has gained the required fuel. But in order to get energy, we need to burn that fuel, right? I mean, think about it. Just by adding petrol in the car, the car will not go forward. That petrol has to be burned to release that energy. Only then your cars and your bikes will go forward. In a similar manner, my cells have to burn that fuel. What I mean by burn here is they have to carry out chemical reaction to release the energy from that fuel and then I can use that energy to do whatever I want to do, to jog, to run, to talk, whatever I want to do, okay? So another important process is after getting all the fuel, my cells have to burn that fuel. Now of course I'm using the burn very crudely. In gentle, we can say chemical reactions to release energy, but I like to use this word burn because even in our daily language we use the same term. We say burn calories, right? What is the meaning of burning calories? It's the same thing. You are basically releasing the energy from the fuel that you just acquired. So that I also have to keep doing. That's another important life process. What else? Well, one thing that I didn't show you while burning the fuel, is that it also generates waste products. So let me go back one step. So once we burn that fuel, some waste products, useless products which are not required for my body also get generated. This is very similar to how again in your cars, once that fuel is burned and energy is released, some waste product is generated and we throw it out from the exhaust pipe, right? In a similar manner, after burning the fuel, after getting all that energy, some waste products are generated and if this is not thrown out from our body, it can be very harmful. And again, we can die because of that. So that's another process. So we need to collect all that waste product and we need to throw it outside our body. And this is where we go to the bathroom to urinate. Of course, we also throw out waste by sweating, okay. So another important life process is to throw the waste away from our body. And if we keep on doing all these things over and over again we can now stay alive. Now before we look at the technical names of these processes, let's see if the same things happen in plants as well. So do plants need to get fuel and raw materials? Yes, they do. The difference is they don't eat, they use the energy of the sunlight and some raw materials around to generate their own fuel. We'll learn later that this is called photosynthesis and the fuel that they generate is glucose molecules. But again, don't worry too much about that right now. We'll just call it as fuel, and they get the raw material that they need from the soil. So the raw soil contains all the nutrients and the water that they need and so the roots of the plant are able to absorb that. So yes, even they have to get this fuel and the raw materials. Okay, do they have to distribute the stuff? Yes. Because whatever they have generated over here needs to be distributed to all the parts of the body so that all the parts of the plant can get the required energy. And similarly the raw materials and the water needs to be distributed to the all the parts of the body so that they can absorb it and use it to grow themselves. Okay. Do they have to burn the fuel? Yes, they do. Whatever energy source they have acquired, they need to burn it in order to get energy and to do all the things for them to grow. And just like what we saw before, by burning that fuel or after releasing that energy, some waste products are generated and they have to throw those waste products outside their body. So they also have to pretty much carry out similar processes, okay? All right. So now let's look at the technical names given to these processes. This process where you gather the energy source and the raw materials, we call that nutrition. Then this process where we distribute things around, we call that transportation. And the process in which we release the energy from the energy source that we acquired, from the fuel that we acquired, we call this respiration. Now, when I was learning this, I got a little confused. I thought respiration meant breathing, right? But usually in biology when we talk about respiration, it's this process what we're talking about, the process in which energy is being released. And of course, we'll talk about all of this in great detail in future videos. And this process where the waste is being thrown out, we call that excretion. And so these are the major life processes that most living things, including you and me, carry out on a daily basis without even thinking about it. And in the future videos, we'll learn in detail about each of these processes.