Lipids are generally water insoluble . it is
biomacromolecule . lipids are simple and complex in form .
The simple lipid is two type fatty acid and glycerol . Fatty acid has carboxyl
group attached with variable R group [the R group has 1 to 19 carbon ] . Palmitic
acid has 16 carbon and arachidonic acid has 20 carbon including carboxyl carbon
. Fatty acid could be saturated (without double bond ) and unsaturated (having
one or more C=C double bond ) .
Glycerol is type of simple lipid and the IUPAC name is
trihydroxy propane .
Many lipid have both glycerol and fatty acid . when
one fatty acid bind with glycerol through easter bond and removal of one molecule water and
form monoglyceride . when two fatty acid bind with glycerol two form
diglyceride and tree fatty acid bind to form triglyceride .
Lipid is also called fat or oil based on their melting
point . oils have lower meting point and remail liquid in winter .
Some lipids have phosphorylated organic compound or
phosphorus present .these groups are called phospholipid . which is present in
cell membrane and more complex structure is present in nerve cell to form
myelin sheath .Lecithin is also example of phospholipid which present inside Lungs
as a surfactant . cholesterol is a type
of lipid .
DIGESTION AND ABSORPTION OF LIPID IN HUMAN. –
After complete digestion fat is absorbed into lymph
not directly to blood . first of all the fatty acid and glycerol incorporated
with bile to form a small droplet called micelles which absorbed into mucosa
cells .now the droplet breaks and reform a very small protein coated globules
called chylomicrons . which is absorbed into the lymph vessels called lacteals .
which is ultimately release into the
blood stream .