Now comes the main part of biosynthesis so terpenes are biosynthesis from primary metabolites basically terpenes are secondary metabolites so they are biosynthesized from primary metabolites so we have two types of pathways the one is the malonic acid pathway and the second is methylerythritol phosphate pathway megalomanic acid pathway so this path will take place in the cytosol as a precursor we need acetyl-coa so three molecules of acetyl-CoA are joined together and they form a malonic acid so a mevalonic acid is a six-carbon intermediate so this six-carbon intermediate is converted into ipp isopentyl diphosphate now in uh the conversion of uh mevalonic acid to an app contain three different kinds of steps like first of all it will have a process known as pyrophosphorylation then decarboxylation and after that dehydration. So we've at the end we have a product which is known as ipp so ipp is the activated five-carbon building block of uh terpenes which is six carbon now like now here comes the question that basically maybe logic ace it contains six carbons while the app contains five so one carbon is released in the form of carbon dioxide so in this picture we can clearly understand what is happening like mevalonic acid is undergoing pyrophosphorylation then decarboxylation and dehydrated dehydration and as a product, we have isopentyl pyrophosphate now this isopentyl pyrophosphate is a five-carbon intermediate which isomerizes into damp dimethylallyl pyrophosphate now which is a 5 both of these are five carbon intermediates and they are responsible for the formation of terpenes next come methylerythritol phosphate pathway. So this path will take place in the chloroplast and other than that we can get ibp from intermediate of glycolysis or from carbon reduction cycle okay so uh in this pathway what happens that as a precursor we have glyceraldehyde 3 phosphate and we have pyruvate so in this picture we can understand the glyceraldehyde 3-phosphate and pyruvate both are three carbon intermediates so they join together and form methyl erythritol phosphate so in this step what is happening that uh when glyceraldehyde 3 phosphate and pyruvate combine it forms 6 carbon but methyl erythritol phosphate is 5 carbon compound so what is happening that air one carbon dioxide is released in this process now as a product we have isopentyl pyrophosphate which is five carbon and it is again polymerized uh sorry isomerized into uh dmapp which is also a five carbon so these five carbon intermediates are responsible for the formation of the beans as we have discussed earlier now what happened that uh isopentyl pyrophosphate and dimethyl phosphate thyroid both of these form many kind of terpenes like it forms uh jeremiah diphosphate which is a 10 carbon so any terpene which contain 10 carbons is termed as monoterpene so after that we also have a friendly cell diphosphate fpp which is 15 carbon so the 15 carbon and you can say 30 30 carbons and both of them are known as the 30 carbon compound were known as tritarpine and the one with 15 carbon is known as sequitur peen after that we have geranius diphosphate so which form dieter beans so any titan which contain 10 carbons is known as monoterpene the one with 20 is known as dieter bean the one with 40 is known as tetraderpine now another main part of the presentation is functions of terpene so.