Hello there, you are watching BioPekmi and in this video we will talk about purines and paramedines. What are they and how do we remember their structure? So let's begin. Purines and paramedines are two groups of nitrogen compiling, rank compound, also called nitrogenous bases that are found in DNA and in RNA. Purines is a six-memboard and a five-memboard nitrogen containing ring fused together whereas paramedine have only a six-memboard nitrogen containing ring. Now how do we remember this? As purines are small words but has a larger structure whereas paramedine has a larger word but has a smaller structure and this way we will memorize this. The purines are adenine and guani whereas paramedines are cytosine and uracine that are found in RNA and thymine that are found in DNA. Purines always pairs with paramedine. In case of DNA adenine pairs with thymine with two hydrogen bond and cytosine pairs with guani with three hydrogen bond whereas in the case of RNA adenine pairs with uracine with three hydrogen bond and cytosine with three hydrogen bond with guani. As DNA is a double-stranded poly nucleotide chain, do you know the reason why there is an constant distance between the two helices? The reason is the purines which always pairs with paramedine. A purines comes a posage to a paramedine. This generate approximately uniform distance between the two strands of the helix. The purines are adenine also known as six amino purines. We must have to remember the IOPSE name of the structure so that we can make its structure. So, adenine also known as six amino purines where the amino group is present at the 6th prime. The numbering should be from here 1 2 3 4 5 6 where the amino group is present 7 8 and 9. In case of purine, the pentoshiger will get attached to the 9 prime of the nitrogenous bases through and glycoside linkage to form a nucleocyte. Guani also known as two amino six oxypuri where the amino group is present on the two prime and oxypuri are present on the 6th prime. Again, the numbering should be from here 1 2 3 4 5 6 7 8 and 9. Again, the pentoshiger will get attached to the 9 prime of the nitrogenous base in case of purine through and glycoside linkage. Now, let's talk about the pyramidines. Cytocene also known as two oxypuri amino pyramidines where the oxy group is present in the two prime and the amino group is present on the 4th prime. The numbering should be from here 1 2 3 4 5 and 6. In case of pyramidine, the nitrogenous bases will get attached to the first prime of the nitrogenous bases with pentoshiger through and glycoside dick linkage. Cytocene is also known as two 4 dioxyp 5 methyl pyramidines where the oxy group is present on the two prime and four prime respectively and the methyl group is present on the 5th prime. In case of uracene that is found in RNA, the other name of uracene is two 4 dioxyp 5, two 4 dioxyp pyramidines where the oxy group is present in the two prime and four prime respectively. That's all for today. Hit like if you find this video informative and don't forget to subscribe to our channel. Thank you.