Lipids & Polysaccharides Flashcards
Polysaccharides
Long-chain polymers of sugars and sugar derivatives
Functions of polysaccharides
- Energy storage
- Cell structure
Most stable enantiomer of glucose
D-glucose
Storage polysaccharides
- Starch in plants
- Glycogen in animals
Polysaccharide identity & function results from ___
- Sugar monomers used
- Type of glycosidic bond
- Amount of branching vs. linearity
What factors determine polysaccharide structure?
- Amount of hydrogen bonding
2. Strength/rigidity of structural polysaccharides
Amphipathic
Hydrophobic but with hydrophilic regions
Lipid functions
- Membrane structure
- Energy storage
- Signal transmission
Fatty acids
Components of some kinds of lipids (amphipathic)
Saturated fatty acids
Each carbon is bonded to the maximum number of hydrogens (long straight chains that pack together well)
Unsaturated fatty acids
Have one or more double bonds, so the chains have bends
Triacylglycerols
- Also called triglycerides
A glycerol molecule with three fatty acids attached to it
- Energy storage
Phospholipids
Contain two fatty acids and a phosphate modified with a polar alcohol (amphipathic)
Steroids
Lipids with a variety of functions
Cholesterol
The most common animal steroid
