You, with Hank and JOhn Green, and lots of others are step by step are the factors that are changing the world. Spending time spreading high quality knowledge. Thank you
@@paulmayer9790 Thats beyond ignorant ahaha. You have no clue how hard the material is in medical school. This is something they would spend 5 minutes on in a lecture and the rest is up to you to learn. You would be blessed to have a doctor who goes above and beyond to learn the material!
You helped me through a few courses in my undergrad studies; and now you are helping me through veterinary school as well! Easily my favorite and the best RU-vid instructor!
Truly a fantastic lecture, clear, concise and well planned. Thank you very much for posting this!! Something that was made rather confusing has now been cleared up so easily by your one video! :)
Hi, I think you may have made a mistake with referencing heparin. The disaccharide is supposed to be heparan sulfate (composed of uronic acid and glucosamine). I only wanted to let you know because my professor made a point that it was not the same as heparin which is used in IVs for hospital patients as an anticoagulant. Other than that, this video was really helpful - thanks!
Heparin is a GAG composed of disaccharides as well (namely iduronic acid and glucosamine) and one of its function is to prevent the coagulation to spread. Heparan sulfate is a GAG composed of glucuronic acid and 2x sulfated glucosamid. It`s a component of basal membranes and cell membrane structures. I don`t think he has made any mistake. The structure and function of heparin is written correctly, according to what i know.
I was taught that the reason that the glycosaminoglycans attract water is because they attract positive ions and that it's the osmotic pressure attracts the water.
08:46 You mentioned that the negative charges on the disaccharide repeats of chondroitin 6 sulfate & keratan sulfate within the aggrecan molecules are responsible for the non covalent interaction between water & aggrecan ! Well , water is not a positively charged molecule to form IONIC BONDS to the negatively charged aggrecan molecules . But it'd rather form HYDROGEN BONDS with water molecules through the hydroxyl groups present in the polysaccharide chain of the aggrecan !
That may be possibility..but non covalent bond is also possible because Oxygen is electronegative atom and for this reason there are partial positive charge on the two hydrogen attached to that oxygen. So these two hydrogen can form ionic interaction with negative charged sulfate ion. Don't you think this is right?
@@sudiptajana1854 Negatively charged sulphate groups would rather form ionic bonds with other positively charged molecules ! Sulphate groups are hydrogen donors in their own right ; while hydrogen bonds are by far the most common kind of bonds between water & other molecules !
@@WhyNot-si4pj sulfate group are hydrogen donor?I don't think so..they don't have any hydrogen attached to them..and still if you think it's H bond acceptor..then I would say F,O,N are.. Secondly, water loves to form hydrogen bond but it makes ionic bond as well (like the NaCl solution..)
