Lipids Flashcards
a class of large biomolecules. Biological substances that are insoluble e in water (non-polar)
Lipids
fat is used for energy during exerctae, empecially after glycogen
in depleted.
Energy Storage
sontributing to membrane tension. rigidity, and overall shape
Cell Membrane
our body cequines energy, fatty acids are released from adipose cells and mobilized for use
Mobilization / Utilization
Lipids were first classified in 1835 by Henri Braconnot in two categories
Solid grease and Fluid oil
These are esters of fatty acid with
vanous alcohols. (Triglycerides, Waxes)
Simple lipids or Homolipids
These are esters of fatty acids with alcohol and possess additional group(s) also (Phospholipids,
Glycolipids)
Compound lipids or Heterolipids
These are thes substance derived from simple and compound lipids by hydrolysis. (Fatty acids, Cholesterol, Steroids)
Derived lipids
are triesters of fatty acids and glycerol. They are nonpolar and
hydrophobic in nature
TRIGLYCERIDES
an alcohol with three carbons.
Glycerol
long hydrocarbon chains with carboxyl group at one end.
Fatty Acid
are esters of long-chain fatty acids and long-chain alcohol. They are solid at room temperature and completely water insoluble. They are formed by the esterification of long-chain fatty acids and
monohydroxy alcohol of higher molecular weight
Waxes
There are two types of waxes commonly used for food coatings
and applications-
paraffin wax and carnauba wax
Consist of glycerol+2 fatty acids + phosphate group.
With a hydrophilic “head” containing a phosphate group and two hydrophobic “tails” derived from fatty acids, joined by an alcohol residue (usually a glycerol molecule)
PHOSPHOLIPID
Hydro means water, philic means attract
Head
Hydro means water, phobic means scared.
Tails
contain a carbohydrate group (attached through a glycosidic bond) in combination with glycerol and fatty acids. It’s the third major class of membrane lipids. The head group of the molecule contains sugar (one or more) connected directly to the hydroxyl group at C1 of the ceramide moiety
GLYCOLIPIDS
have no double or triple bonds. They are a simple, unbranched, and linear chain of CH2 groups connected with a carbon-carbon single bond and one carboxylic acid at its end. Their general formula is CH3-(CH2)n-COOH wheren represents the number of methylene groups
Saturated fatty acids
have one or more double or triple bonds.
So, they can either be monounsaturated or polyunsaturated. The
naturally occurring fatty acids are generally in the cas
configuration, rather than in trans configuration.
Unsaturated fatty acids
is often called ‘bad cholesterol because too much
of it can clog up your arteries and lead to health problems later on,
such as heart disease, heart attacks and strokes.
CHOLESTEROL
occur in plants, animals, yeasts, and molds but not in bacteria. They may exist in free form or combined with fatty acids or carbohydrates.
Steroids
