 different classes of carbohydrates, the monosecrides first the contents monosecrides, physical chemical properties of monosecrides types are on the basis of size types are on the basis of functional group chain and ring structures and the importance so first we define monosecrides monosecrides, carbohydrates the first class is the monosecrides first the monosecrides, then the disecrides and polysecrides so monosecrides, mono means one and sacrides means sugar so it is the simplest sugar so we will not define monosecrides monosecrides are the simplest sugars which cannot be broken down into further simple carbohydrates because if you break down one further one or two will not be formed so if you break down single unit further carbohydrates cannot be formed let me clarify a little monosecrides do not become further carbohydrates due to breaking down monosecrides this is the break down of glucose glucose is a monosecrid but further the molecules will not be carbohydrates like glucose break down makes pyruvate in glycolysis so pyruvate is not in the carbohydrate category so this is why so glucose is the most common type of monosecrides physical and chemical properties of monosecrides physical and chemical properties of monosecrides or we will take an overview monosecrides are the first both famous properties of monosecrides they are sweet in taste all monosecrides are sweet in taste like glucose, mannose, galactose all these are sweet in taste they are readily soluble in water monosecrides are easily soluble in water if the solid form is present in pure form they will form crystals so they are crystalline in nature crystalline means that it is in liquid then it will make solution but when it is in pure form when it is in pure form then it is crystalline if salt is added in water then it is soluble but if salt is in pure form then crystalline form appears so monosecrides also make crystals all the monosecrides are reducing sugars most of them are simple but in general we say that all the monosecrides are reducing sugars reducing sugars are sugars which oxidize other molecules which are reduced there are mat lines they can reduce mat lines or there are other groups they can oxidize other molecules that is why we reduce them they are reducing sugars types of monosecrides we can do types on two bases of monosecrides first is on the basis of size i.e. on the basis of carbon atoms how many carbon atoms are present in carbon chain in its backbone and skeleton monosecrides size consists of 3 to 7 carbons 3 carbon monosecrides are called trios 4 carbon tetroses 5 carbon pentoses 6 carbon hexoses and 7 theptoses 3 to 6 i.e. 3, 4, 5 and 6 carbon are abundant in nature if we look at its structure you can see the structure the first one we have is glyceraldehyde if we look at glyceraldehyde it is a 3 carbon 3 carbon molecule rithrose 4 carbon ribose 5 carbon and glucose is the 6 carbon molecule glyceraldehyde 3 carbon is a triose rithrose 4 carbon is a tetrose ribose 5 carbon is a pentose and glucose 6 carbon is a hexose focus on the structure there is a functional group on one end there are hydroxyl group with the rest of the carbon it is important for the carbon to be polyhydroxy there are more than 1 hydroxyl group there are 3 carbon group there are 2 hydroxyl group for 1 functional group if there are 6 carbon group then there are 5 hydroxyl group with 5 carbon group and 1 functional group with 1 attachment monocyclitis is the second classification on its functional group base first is carbon skeletonary base there are many carbon atoms we give it a norm for functional group some monocyclitis is L-dehyde L-dehyde is a functional group L-dehyde is L-doses K-tone is a functional group K-tone is a functional group we call it K-toses a very simple example glucose and fructose glucose is 6 carbon molecule fructose is 6 carbon molecule but the glucose has L-dehyde so we call it as aldohexose when the fructose has this ketone group so what we call it when the aldohexose is called as ketohexose so in this way we have two categories of K-tose these are in front of you L-dehyde group is called CHO group when the CHO is combined L-dehyde always comes at an end when the ketone group is in this C-double bond O-carbon both have carbon so if you see ketone group is not at the end it is somewhere in the centre or somewhere in the middle when the fructose is at number 2 position on number 1 position ketone group does not exist it will exist the next is about the structure of monocyclitis when you see the structure of monocyclitis it is a simple carbon skeleton where monocyclitis is linked so there are two structures one is called chain structure chain structure is linearly carbon then carbon then carbon three carbon are linearly attached one carbon will be functional group and two will be hydroxyl group so if it is 6 carbon then 5 will be linear 6 to 6 and 5 to be hydroxyl group this structure is linear structure usually as we have monocyclitis carbon number 4 to be onward if we provide them with aqueous environment i.e. if we put it in water then the chain structure will make ring it means it has cyclic structure or ring structure carbon number 3 does not make ring structure whereas 4, 5, 6 and 7 will make ring structure rings are two types some are carbohydrates some are carbohydrates which make 5 corner ring 5 corner ring is called furanose ring and 6 corner ring is called pyranose like glucose makes 6 corner ring that is why we call it pyranose pyranose for 6 corner ring fructose makes 5 corner ring that is why we use fructose furanose cover for it important of monocyclitis who can deny the importance of glucose most important for survival if we look at the importance of glucose in humans all the important activities mainly glucose break down gives energy and we are surviving it this is not only for humans all animals even for bacteria and plants other energy sources are also used primary energy source is glucose that means the first job of monocyclitis is to provide energy energy as source of energy which is used let us clear some other things that in glucose energy is carbon hydrogen bonds CH bond the more carbon hydrogen bonds are there the more energy it will give it does not give hydroxyl group energy it will give carbon hydrogen it will not provide hydroxyl group energy the second energy that is they are building material for complex polysaccharides complex molecules like in plants all the structure of plants are made of cellulose and cellulose is made of glucose molecules our body contains glycogen similarly plants have starch insects are made of exoskeleton chitin all the complex molecules structures are made of monocyclitis it is like building of an intium monocyclitis is made of big molecules where different structural activities are performed