Lipids Flashcards
What are the 3 major types of lipids found in foods and in the body?
- triglycerides
- phospholipids
- sterols
Describe the general structure of a triglyceride.
contains 1 molecule of glycerol and 3 fatty acids (chains of carbon atoms)
What is monounsaturated fatty acid? Identify the major food sources.
a fatty acid that lacks 2 hydrogen atoms and has one double bond between carbons (MUFA)
- palmitoleic acid
- oleic acid
- olive oil, canola oil
What is polyunsaturated fatty acid? Identify the major food sources.
a fatty acid that lacks 4 or more hydrogen atoms and has 2 or more double bonds between carbons (PUFA)
- linoleic acid
- linolenic acid
- seafood (omega-3 fatty acids), nuts and seeds, plant oils
What is saturated fatty acid? Identify the major food sources.
a fatty acid carrying the max possible number of hydrogen atoms
- stearic acid
- cocoa butter, palm oil, palm kernel oil, coconut oil, butter, margarine and shortening
How and where are dietary lipids are digested and absorbed?
In the stomach fat is separated from other food substances. In the small intestines, bile emulsifies fats while enzymes digest them. The intestinal cells absorb the fats. Long-chain fatty acids form a large lipoprotein structure called a chylomicron that transports fats through the lymph system.
What is the role of the lipoproteins (chylomicrons, LDL,andHDL) in transporting lipids throughout the body?
High density Lipoprotein (HDL) - picks up cholesterol from dying cells, removes cholesterol from bloodstream, synthesized by liver
Receptor pathway: LDL - taken up by liver via this pathway when a diet low in saturated fat and cholesterol is consumed
Outer shell of phospholipids, transporting triglycerides and protein
What are the major functions of fat in the body?
Provide energy, storage, insulation, protection (cushion organs), cell membrane components, eicosanoid production, transport fat-soluble vitamins
