Lipids Flashcards
What elements do lipids contain
Carbon, hydrogen, oxygen
What’s the general structure of a triglyceride
3 fatty acids combined with one glycerol
What bond forms between glycerol amd fatty acids
Ester bond
What is a saturated fatty acid
No double bonds between carbon atoms
What is an unsaturated fatty acid
Contains one or more double bonds between carbon atoms
How can lipids be hydrolysed?
-heating with acid or alkali
-using lipase
What is the function of triglycerides
-energy store
-some vitamins are only fat soluble
What are the properties of a triglyceride
-have a high amount of carbon carbon-hydrogen bonds so release twice as much energy as carbs.
-release water when respired
-non-polar so osmotically inactive
-waxy so prevents water loss in plants
What is a phospholipid
Lipids that contain a phosphate group. Replaces one of the fatty acids
What is a phospholipid made of?
1 glycerol, 2 fatty acids, 1 phosphate group
How would you describe the structure of a phospholipid
Polar hydrophilic head containing a phosphate group and a non polar hydrophobic tail made of fatty acids
What do phospholipids form?
Phospholipid bilayers
Why are phospholipid bilayers important?
It’s what the cell membrane is made of so allows lipid soluble molecules to pass through quickly
How do you test for lipids?
-add a sample to ethanol
-mix so the fat dissolves
-add to water
-mix
White emulsion indicates lipids present
