Biological Molecules - Lipids Flashcards
What are lipids composed of
-carbon
-hydrogen
-oxygen
Why are lipids non-polar
They do not have beta charges so separate in water (polar solvent) and are insoluble
-miscible
What are fats and oils
Triglycerides
How do triglycerides form
Form glycerol and 3 fatty acid molecules in a condensation reaction
In what reaction do they form
Condensation reaction
What are saturated fatty acids
Ones that contain no double bonds and is saturated with hydrogen which means that it cannot accept anymore hydrogen
What is an example of a saturated fatty acid
Lard
What are unsaturated fatty acids
Have one or more double bonds between carbon atoms
What is the glycerol linked to in a unsaturated fatty acid
An ester bond
What effects the chemical and physical properties of fatty acids
The type of fatty acid present
What is the structure of fatty acids and how does it relate to its properties
-high ratio of carbon- hydrogen bonds - so excellent source of energy
-low mass to energy ratio - good storage molecule
-large and non polar and insoluble in water so don’t affect water potential(osmotic)
-high ratio of hydrogen to oxygen atoms allow to release water when oxidised- advantageous in hot/dry conditions - metabolise fat
What is a phospholipid made of
Glycerol
Two fatty acids
Phosphoric acid
What part of the molecule is attracted to water
The head - hydrophilic
What part of the molecule repels water
The tail - hydrophobic
Non-polar
What forms in an aqueous environment due to the non-polar and polar parts
A lipid bilayer- this provides a barrier inside and outside of the cell
