1. Lipids
Objective:
B2 - Compare the structures & functions of carbohydrates, lipids, proteins, & nucleic acids & their organization into long complex molecules

2. Function: Consist of: Characteristics: Energy storage
Mostly Carbon & Hydrogen with some Oxygen
Characteristics:
Hate water (hydrophobic)
Insoluble (won’t dissolve) in water

3. Examples of Lipids Fats (helps conserve heat) Oils
Waxes (waterproof covering)
Butter
Phospholipids (part of cell membrane)
Steroids (cholesterol, estrogen, testosterone)
steroids (not artificial ones, but cholesterol, which is the most common type, estrogen, testosterone, bile salts)
Waxes are similar to fats except that waxes are composed of only one long-chain fatty acid bonded to a long-chain alcohol group attached. Because of their long, nonpolar carbon chains, waxes are extremely hydrophobic (meaning they lack an affinity for water). Both plants and animals use this waterproofing characteristic as part of their composition. Plants most noticeably use waxes for a thin protective covering of stems and leaves to prevent water loss. Similarly, animals employ waxes for protective purposes; for instance, earwax in humans prevents foreign material from entering and possibly injuring the ear canal area.

4. Building Blocks of Lipids
(monomers)
Glycerol
Fatty acids

5. Fats (triglyceride)
Always have 3 fatty acids
There are 2 different kinds:
Saturated (no double bonds between the carbon atoms) Solid at room temperature Examples: butter
Unsaturated (have a double bond between two carbon atoms) Liquid at room temperature Examples: oil
If there is more than one double bond, it is called a polyunsaturated fat. Most vegetable fats are unsaturated (think vegetable oil).
Polyunsaturated (have more than one double bond)

6. Phospholipids
Like fats, but only have 2 fatty acids (this causes the glycerol, which now includes a phosphate group to like water, but the tails still hate water)
Has a hydrophilic end and a
hydrophobic end

7. Phospholipid Structure
Because it has a “split personality,” this forces this lipid to assume an interesting structure when in the presence of water. The hydrophilic (phosphate head side) surrounds the hydrophobic (fatty acid tails) shielding the tails from exposure to water
This makes up the phospholipid bilayer (cell membrane) of all cells