Lect. 4 Lipids Flashcards
Main categories of lipids
- Neutral fats (triglycerides & fatty acids)
- Steroids
- Phospholipids
What are lipids used for?
- energy storage
- structural components of membranes and hormones
Types of Lipids
Triglycerides
Water insoluble
Lard, suet, olive oil, peanut oil, butter
Types of Lipids
Fatty acids
Water insoluble
Linoleic, linolenic
Types of Lipids
Steroids
Membrane component, hormones
Estrogen, vitamin D, cholesterol
Types of Lipids
Phospholipids
Amphipathic; membrane component
Lecithin (2 fatty acids, glycerol, phosphate + choline)
What are triglycerides composed of?
smaller molecules:
- fatty acids (3)
- glycerol
What are fatty acids composed of?
often long hydrocarbon tail (16/18 C) with a carbozyl gr. (-COOH) at one end
lipid molecule
What is glycerol composed of?
a 3-carbon alcohol containing 3 hydroxyl (-OH) gr.s
Fatty Acids
Saturated fatty acids contain:
the max number of H atoms bonded to the C skeleton (no =bonds)
solid at room temp.
butter, palmitic acids
Monounsaturated acids contain:
one double bond
liquid at room temp.
found in fish, plants. olive oil. oleic acid
Polyunsaturated fatty acids contains:
more than one =bond
liquid at room temp.
nutritionally the best type of lipid. linseed oil, linoleic acid.
Unsaturated fatty acid
A cis fatty acid has H atoms located on:
the same side of the =bond which gives the chain a pronounced kink
found in nature, , in foods like olice oil.
