Lipids

=Erin Flannelly, Kyle Cote, Daniella Delgado= =Lipids - Diverse Hydrophobic Molecules = = - Little to no affinity for water = - Consist mostly of hydrocarbons 3 Types: 1. Fats 2. Phospholipids 3. Steroids FATS: Fats - constructed from two types of smaller molecules (glycerol and fatty acids)
 * major component is to store energy

The “tail” of a fatty acid is a long hydrocarbon chain, this is what makes it hydrophobic. The “head” is hydrophilic. The tails are all connected by single bonds between the carbons, they are called saturated fats.


 * [[image:glycerol.gif]] || [[image:fatty_acid.jpg width="280" height="181"]] ||

Glycerol is an alcohol with three carbons each bearing a hydroxyl group (fat) Triacyglycerol- Three fatty acids linked to one glycerol molecule. There are two types of fatty acids: saturated and unsaturated Saturated fatty acids- A fatty acid in which all carbons in the hydrocarbon tail are connected by single bonds, thus maximizing the number of hydrogen atons that can attach to the carbon skeleton. Unsaturated fatty acids- A fatty acid possessing one or more double bonds between carbons in the hydrogen tail. Such bonding reduced the number of hydrogen atoms attached to the carbon skeleton. PHOSPHOLIPIDS: Phospholipids are major components of cell membranes Phospholipids- are similar to fat, but they have only two fatty acid tails rather than three. (hydrophilic)

hhtp://kvhs.nbed.nb.ca/gallant/biology/phospholipid_structure.jpg

STEROIDS: Steriods include cholesterol and certain hormones. Steriods- are lipids characterized by a carbon skeleton consisting of four fused rings. EX: Cholesterol http://telstar.ote.cmu.edu/biology/MembranePage/images/chol_struct.jpg

Importance: Lipids store large amounts of energy Cushions vital organs/insulates body Major components in Cell Membranes Produces many hormones in animals and humans

(Chapter 5 in Bio text book)