 In this module, we will be discussing metabolic fates of nutrients in heterotrophs. So, we have already mentioned the heterotrophs, if those organisms which depend upon the food which is prepared by the organisms, plants or animals themselves, they are also eaten up by the heterotrophs. So, nutrients that a heterotroph ingests, they can be divided into two types. For example, we call them as the macronutrients and then the micronutrients. So, we can divide these heterotrophs into two different types. Those organisms which use macronutrients and those organisms which use micronutrients. So, in the macronutrients, we have classified them as carbohydrates, fats, proteins. So, these are the macronutrients. Now, carbohydrates are also different types. Some are monosecrites like glucose, electrons, fructose. So, all these are the monosecrites. This is only a single unit. That is, you must have read it in your biochemistry. Glucose, which is C6H12O6, this is a simple molecule. It is also a diffusible molecule. It can pass through the cell membrane. Then, there are certain carbohydrates which are said to be the disaccharides. The two monomers, they unite together to form a bigger molecule, which is a disaccharide. For example, sucrose. Sucrose is what we call sugar. We use sugar in our home. So, this is sucrose. This is the combination of two monomers, which include glucose and fructose. Likewise, there is a disaccharide, which occurs in milk, which contains galactose and glucose. These monomers unite together to form a double molecule. Then, there are polysaccharides. In polysaccharides, there are starches and glycogen. Starchs, they are very long chains of glucose molecules to form bigger molecules, very huge molecules. And till the time they do not break down, they do not convert to glucose. So, these starches, they are of no use to the animal. Till the time they are digested, they do not convert to simple monomers. And same is true with glycogen. Then comes the fat. The fats are again the combination of fatty acids. And what are the fatty acids? They are found with glycol. And they form a large molecule. And there are oils, which we are familiar with, which we get from plant seeds. So, there are a variety of oils, which have some addibles and some non-addibles. So, they are said to be the fats. Then comes micronutrients. Micronutrients are needed in a very small amount. That is why we call them as the micro. So, they include organic vitamins. We will talk about this in detail. And in nutrition, vitamins play a very important role. And these are the organic materials in which the animals get it. And what is this? This is water in a major amount. So, this is micronutrients. So, till now, we have seen the requirements of heterotrophs in this module. And these are macronutrients, which we get from the bulk of food. And some are micronutrients. And they are equally important. These are not macronutrients that we use. We do not use micronutrients. Both play an important role. And all these things are made up of food. And this food goes into our body. And then it gets energy from here. And our building material is maintained. The product blasts are added up. And the wear and tear that is also replaced by only these nutrients. So, this is all about.