What is the length of a triglycerides? how are glycerol and fatty acids “connected” to make a triglyceride?

Every fatty acids has a long hydrocarbon chain (with even amounts of carbons, usually 16 or 18) and a carboxyl group.

glycerol is a 3-carbon molecule with 3 -OH groups.

fatty accids and glycerol can be connected by single or double bonds, depending on if the fatty acid is saturated or unsaturated.

when a lipid forms, the -COOH functional groups of 3 fatty acids react with -OH groups of glycerol.

this leaves 16, 18, or 20 carbons, making a triglyceride 16, 18, or 20 carbons long.

hope this helps!