How is cholesterol transported around the body? When it leaves the liver, what is its destination and use?

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All right. Hello everyone. So this question is a true or false. It says cholesterol is transported from the liver throughout the body by HDLs to be converted to bile acids for excretion. All right. So based on the statement given, even though we're not quite sure if it's true or not, we can see that HDL is referring to a type of lipoprotein and there are various types of lipoproteins in the body. So let's go ahead and give some more context recall that lipoproteins are spherical compounds that are made up of lipids and proteins. And so their function is to transport lipids throughout the body as needed. There are four main types that we can discuss. So let's go ahead and go through all of them. Now, the first of which are known as Chlo microns and Chylomicron are best known to transport all dietary lipids, they're known to transport all dietary lipids and they can be found from the intestines to the liver and in adipose or other tissues. Now, from here, we talk about lipoproteins with varying varying densities. First, we have VLDL which stands for very low density lipoprotein and these guys are responsible for transporting tri ao glycerol or tags that are synthesized in the liver. So, tr ao glycerol from the liver are transported elsewhere by VLDLS. From that we move on to low density lipoproteins or LDLs for short. And LDLs transport cholesterol. But it's important to distinguish LDL from HDL. That is the high density level protein because both of these transport cholesterol, the difference is from where right. So LDLs are going to transport cholesterol that was synthesized in the liver. By contrast, HCL is going to transport cholesterol from dead or dying cells. Its essentially rescuing that cholesterol from dead or dying cells in the case of HDL. Now, what's interesting about HDO, what's interesting about HDL is that some of them can be converted into bile and excreted. So now let's go back to the statement given, it says that cholesterol transported from the liver throughout the body is done by HDLs and this is not true, right? Because as mentioned before, cholesterol synthesized from the liver is transported elsewhere by LDLs. And so once that cholesterol is synthesized in the liver, LDL is transported to various other tissues. So that that cholesterol can be used in cell membranes and also for the synthesis of steroid hormones. By contrast, HDL is the one that rescues cholesterol from dead or dying cells so that it can be transported back to the liver where it can be converted into bile and excreted. So here the statement is false. And So, with that being said, thank you so very much for watching and I hope you found this helpful.

How is cholesterol transported around the body? When it leaves the liver, what is its destination and use?

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