Biochemistry - Part III (Lipids)

2. Fats (Lipids) A molecule containing carbon, hydrogen, and oxygen. Our most concentrated energy source! Slow burning, also referred to as lipids. Contain twice the energy per gram as carbs/proteins. Fats are areas of storage for energy and structure (cell membranes, myelin around nerve cells, etc.)

2. Fats (Lipids) con’t The three building blocks of fats are: 3 fatty acids , carboxyl group & glycerol Carboxyl group

Fats (lipids) cont’d These are recognizable because of their backbone of glycerol and because each fatty acid contains a long hydrocarbon chain, the end of which combines with glycerol!

Fats (lipids) cont’d At room temperature, some fats/lipids are solids such as butter, lard Some are liquids (called oils). A saturated fat is one where all carbons are “saturated” with hydrogen bonds. These tend to be straight molecules, so they “stack” tightly and are solid at room temperature.

Fats (Lipids) cont’d An unsaturated fat is where one or more double bonds between two carbons exist, meaning not all bond sites are saturated with hydrogen (mono=1 double bond, poly=multiple double bonds). These tend to have “kinks”, and as a result the fat molecules don’t stack tightly… if they can’t get too close to each other, they remain liquids at room temperature.