The Formation of Lipids

The Formation of Lipids

This assignment is primarily about lipids, triglyceride, unsaturated

and saturated fats I will be stating the formation of lipids and what

they are made of.

Lipids are a group of substances which include fats and oils, steroids

which include cholesterol and some of the sex hormones, and various

other substances such as the waxes which cover insect bodies and plant

leaves. Lipids are a mixed group of hydrophobic compounds composed of

the elements carbon, hydrogen and oxygen. Triglycerides are commonly

called fats or oils. They are made of glycerol and fatty acids. They

are present in a wide range of living organisms and help to insulate

and protect animals such as seal and marine birds.

If there are no C=C double bonds in the hydrocarbon chain, then it is

a saturated fatty acid (i.e. saturated with hydrogen). These fatty

acids form straight chains, and have a high melting point.

If there are C=C double bonds in the hydrocarbon chain, then it is an

unsaturated fatty acid. These fatty acids form bent chains, and have a

low melting point. Fatty acids with more than one double bond are

called poly-unsaturated fatty acids.

One molecule of glycerol joins together with three fatty acid

molecules to form a triglyceride molecule, in another condensation

polymerisation reaction.

Phospholipids have a similar structure to triglycerides, but with a

phosphate group in place of one fatty acid chain. There may also be

other groups attached to the phosphate. Phospholipids have a polar

hydrophilic head and two non-polar hydrophobic tails.

They may form a double-layered phospholipids bilayer. This traps a

c...

... middle of paper ...

...unds so are good for energy

storage. Carbohydrates can be mobilised more quickly, and glycogen is

stored in muscles and liver for immediate energy requirements.

Triglycerides containing saturated fatty acids have a high melting

point and tend to be found in warm-blooded animals. At room

temperature they are solids (fats), e.g. butter, lard, and

Triglycerides containing unsaturated fatty acids have a low melting

point and tend to be found in cold-blooded animals and plants. At room

temperature they are liquids (oils), e.g. fish oil, vegetable oils.

Glycerol is a small, 3-carbon molecule

Fatty acids are long molecules with a polar, hydrophilic end and a

non-polar, hydrophobic tail. The hydrocarbon chain can be from 14 to

22 CH2 units long, but it is always an even number because of the way

fatty acids are made.