Biological Molcules - Fats Flashcards
What are lipids made of?
Triglycerides
What type of molecule is a triglyceride?
A long polymer held together by many bonds
What is a key property of lipids and why?
Insoluble - doesn’t cause the cell to swell by osmosis
How are triglycerides found in the body?
They form insoluble droplets in cells with hydrophobic tails on outside - micelles
What is a triglyceride made up of?
- 1x glycerol
- 3x fatty acid tails
What bonds hold triglycerides together?
Ester bond
Draw a triglyceride
See notes
Are the fatty acid tails hydrophobic/hydrophilic?
Hydrophobic
Are the glycerol molecules hydrophobic/hydrophilic?
Hydrophilic
Where are saturated lipids found?
Animal fats
Where are unsaturated lipids found?
Plant fats
What does saturated lipids mean?
No carbon-carbon double bond between carbon atoms
What does unsaturated lipids mean?
Carbon-carbon double bond between carbon atoms
What do the chains of unsaturated lipids contain?
Kinks
Do unsaturated/saturated lipids have a higher melting point?
Saturated
Define “cholesterol”
Type of lipid needed in small amounts for normal body functions
What is cholesterol needed for?
Maintaining cell membranes
How is cholesterol transported in the blood?
Attaches to proteins to form lipoproteins
What are the two types of lipoprotein?
- LDL : low density lipoprotein
- HDL: high density lipoprotein
What are HDLs mainly made of?
Protein
What do HDLs do? 4
- Lower blood cholesterol
- Carry cholesterol from blood to liver where it is destroyed
- Reduce fat deposits
- Reduce formation of atheroma
What are LDLs mainly made of?
Lipids
What do LDLs do? 5
- Increase blood cholesterol
- Carry cholesterol from liver to the blood
- Increase fat deposits
- Increase formation of atheroma
What is the best ratio of HDL:LDL to minimise CVD risk?
High HDL:LDL ratio
Why does increased LDL/blood cholesterol mean increased CVD risk?
- Increased atheroma
- Increased blood pressure
- Increased blood clotting
