Lipids and Fatty acids Flashcards
what are lipids?
Biological molecules comprised mainly of chains of hydrocarbons.
Fatty acids, waxes, sterols, some vitamins etc…
They are amphiphilic, but the hydrocarbon chain generally makes them act hydrophobic.
Only soluble in non-polar solvents.
Diverse range of functions in the body: energy storage, cellular signalling, cellular structural components.
amphiphilic
a molecule having both hydrophobic and hydrophilic regions.
fatty acids
These are carboxylic acids, joined to a long aliphatic hydro-carbon chain.
Fatty acids can undergo saponification reactions to make soap and glycerol.
Fatty acids can be divided into several types.
Saponification
Is the process in which triglycerides are combined with a strong base to form fatty acid metal salts during the soap-making process.
saturated
means that every carbon in the chain has a single bond to another carbon and any other bonds are taken up by hydrogen.
Unsaturated
means that one or more carbon double bond is present in the chain.
mono-unsaturated
one carbon-carbon double bond is present.
poly-unsaturated
Two or more carbon-carbon double bonds are present
trans fatty acids
naturally occurring fats, however, higher levels in processed foods.
These increase the amount of Low Density Lipoproteins (LDLs) and lower High Density Lipoproteins (HDLs).
found in butter, milk, biscuits, confectionary, crisps etc.
cis fatty acids
naturally occurring fats, however, processing foods can hydrogenate this bond leading to the generation of a saturated fat , or can cause isomerisation, leading to the formation of a trans fat.
This increases HDLs
Found in olive & veg oil, nuts, avocado, however, most foods containing cis fat will also have trans fat.
hydrocarbon chain
the other end which can interact with lipids.
carboxylic acid
One end which can interact with water.
Types of Fatty Acids In Biochemistry
Triacylglycerols (TAGS), Waxes, Glycerophopholipids, Sphingolipids, Glycosphingolipids.
Glycerol
3 carbon sugar alcohol
Odourless, colorless, slight sweet taste.
Used as a bulking agent in many products.
what a is the bond that joins the molecules in a triacylglycerols
an ester bond
