Lecture 19 - Biological Molecules III Flashcards
what are lipids?
lipids (fats) are esters of long chain fatty acids and glycerol
what are lipids the main component in?
lipids are the main component in cell membranes
what lipids are not miscible with water?
lipids like glyceryl trioleate (olive oil) and srearin
how does water and triglycerides react when in contact with one another?
when mixed together the triglyceride spreads out on the surface of the water in a very thin layer
as an ester how can triglycerides be hydrolysed?
as an ester, triglycerides can be hydrolysed by heating with aqueous sodium hydroxide - the resulting sodium salt is what we called soap!
what happens to soap when suspended in water?
when soap is suspended in water the carboxy groups stick out into the polar water and the greasy hydrocarbon side chains associate on the inside of the globule (micelle)
how do the hydrophobic tails interact with each other within the phospholipid bilayer?
the greasy hydrophobic tails interact with each other using van de waals interactions
what do enzymes provide?
enzymes provide a reaction surface and environment through brining reactants together in the appropriate orientation and weakening bonds
binding between a substrate and an enzyme involves:
intermolecular interactions between substrate and enzyme surface
more sophisticated understanding of enzyme-substrate binding:
the enzyme and substrate mould themselves to each other
competitive inhibitor:
drug molecule that binds reversibly to an enzyme and competes with the natural substrate is known as a competitive inhibitor
why are irreversible inhibitors irreversible?
due to them forming non reversible covalent bonds which ruin the active site
what typically are phospholipids?
phospholipids are typically glycerol DIESTERS with fatty acids with the remaining hydroxyl group bearing a polar phosphate group
what determines the rer activity and specificity of an active site?
the chemical strucutre of the protein
