Lipids Flashcards
what are the two groups of lipids
Triglycerides and phospholipids
how is triglycerides formed
via the condensation of one molecule of glycerol and three molecules of fatty acid
how is an ester bond formed
condensation between glycerol and the 3 fatty acid( RCOOH)
what is the R groups
the variable group that gives each amino acid its unqiue chemical and physical properties
how to figure out whether the diagram is saturated or unsaturated
saturated: hydrocarbon chain has only single bonds between carbon atoms
unsaturated: the hydrocarbon chain consist of at least one double bond between carbon atoms
describe the properties of triglycerides
large ratio of energy storing carbon-hydrogen bonds compared to the number of carbon atoms : excellent store of energy
high ratio of hydrogen-oxygen atoms : acts as a metabolic water source. Triglycerides can release water if oxidised - essentials for animals such as camels in deserts.
the tails are so long + hydrophobic (repels water molecules) : you can store lots of triglycerides away as energy storage without affecting water potentials + osmosis (cells do not burst)
relative low mass to energy ratio: can store lots of lipids as energy storage without making animals mass too heavy .
what is the structure of phospholipids
made of a glycerol molecule and two fatty acid chains and a phosphate group ( replaces the third fatty acid)
how are phopholipids formed
two fatty acids bond to the glycerol via two condensation reactions resulting in two ester bonds
describe the properties of phospholipids
-phospholipid head is hydrophillic and the phospholid tails are hydrophobic
-forms a phospholid bilayer where the head faces towards the water
-centre of the bilayer is hydrophobic which mean water soluble subtances cannot easily pass through
-cell membrane acts as a barrier to those substances
