Lipids Flashcards
Lipid
Non polar molecules
Hydrophobic-insoluble in water
Fats, oils, phospholipids, steroids, wax
Fat/oil
Consists of glycerol and fatty acids.
The fatty acids attach to each of the glycerol 3 carbons with ester bond through oxygen atoms.
Also called triglycerides/triacylclycerols
Fatty acid
May be saturated or unsaturated
Saturated- most are solid at room temp
Unsaturated- most are liquid at room temp
Mono saturated- 1 carbon-carbon double bond (olive oil)
Poly unsaturated- more than 1 carbon-carbon double bond (canola oil)
“Saturated” because it isn’t possible to add more hydrogen
Unsaturated usually from plant origin
Cis- H present on same plane
Trans- H causes bend in chain, H on different planes. Keeps it liquid at room temp
Phospholipid
Major plasma membrane constituents.
2 fatty acids attached to a glycerol, and a modified phosphate group occupies the glycerol’s third carbon.
Amphiaphatic (amphi=both) molecule. Has both a hydrophobic and hydrophilic part.
Fatty acid-hydrophobic
Phosphate group- hydrophilic
In plasma forms structure tail to tail
Steroids
Fused ring structure.
Cholesterols most common.
Liver synthesizes cholesterol and is the precursor to many steroid hormones such as testosterone and estradiol.
Cholesterol is precursor to bile salts.
Bile salts help emulsify fats and their absorption by cells.
Cholesterol is precursor for vitamin d.
Sterols (cholesterol in animals, phytosterol in plants) components of plasma membrane of cells.
Trans fat
Artificially hydrogenated oils to make them semi-solid. H gas bubbled through oils to solidify them. Example-margarine, shortening.
Omega fatty acid
Omega3 and omega6- polyunsaturated double bond connects 3rd carbon from hydrocarbons chain end to neighboring carbon
Wax
Hydrophobic, prevents water from sticking on surface.
Long fatty acid chains chesterfield to long chain alcohols
