Why do we need Lipids?
• Plasma membranes• energy• protection• hormones• Insulation
• Waterproofing
Lipids:
Carbon, hydrogen and oxygen (lower ratio of oxygen than in carbohydrates)
Not polymers like starch and protein (it's not a chain of the same monosaccharides)
Soluble in alcohol and acetone
Fats are solid, at room temperature oils are liquid
Group 1: Triglycerides (the main type of fat we eat)
Oops! This image does not follow our content guidelines. To continue publishing, please remove it or upload a different image.
Oops! This image does not follow our content guidelines. To continue publishing, please remove it or upload a different image.
Oops! This image does not follow our content guidelines. To continue publishing, please remove it or upload a different image.
Saturated > Single C-C bond
Unsaturated > Double C=C bond
Oops! This image does not follow our content guidelines. To continue publishing, please remove it or upload a different image.
How to form a Triglyceride?
Oops! This image does not follow our content guidelines. To continue publishing, please remove it or upload a different image.
Group 2: Phospholipids
•One fatty acid is replaced by a phosphate group, so the glycerol combines with two fatty acids and one phosphate group
•The phosphate group has a negative charge (polar) whereas the fatty acid tails do not have a charge (non-polar)
•This makes the phospho-glycerol head hydrophilic (attracts water - soluble) and the fatty acid tails hydrophobic (repels water- not soluble)
Oops! This image does not follow our content guidelines. To continue publishing, please remove it or upload a different image.
Although Cholesterol wasn't mentioned it's still good to know:
Oops! This image does not follow our content guidelines. To continue publishing, please remove it or upload a different image.
Emulsion Test for Lipids:
Crush sample, add to Ethanol, add water and shake
If it turns milky white, lipids are present
YOU ARE READING
A-Level Biology
RandomAll the A-Level Biology I do in my two years of college. Yay!
