Lipids Flashcards
U1L5
What are lipids?
Lipids are Fats, Oils, Cholesterols and Hormones.
They are primarily composed of C, H, O and P (for Phospholipids). Because of the long Non-Polar Carbon chains, it makes the molecule Non-polar which is the reason why fats are Hydrophobic.
Fats store the most energy 9kcal/g
What is the molecular formula for Lipids?
Cn-H2n-O<1n
Less Oxygens which lead to insolubility.
What are the three types of Lipids?
Triglycerides
Sterols
Phospholipids
What are Triglycerides?
Triglycerides are the most common form of energy storage in plants and animals.
It is a molecule composed of three fatty acid chains which are attached to a Glycerol backbone.
What are fatty acids?
Fatty Acids are long hydrocarbon chains with a carboxyl group.
Carbon chains differ in length and points of unsaturation.
What are the two types of fatty acids?
Saturated Fats (saturated with Hydrogen bonds).
Unsaturated Fats (Carbons that have either double or triple bonds.)
What are characteristics of Saturated Trigylcerides?
Theya re typically solids at room temperature. They also are primarily from animal sources.
They are more shelf stable then there unsaturated counterparts and taste better.
They are associated with health risks.
What are unsaturated fats?
They are fatty acids that have double or triple bonds.
They form bent/kinked carbon chains.
Can be either Mono or Poly unsaturated.
What are characteristics of unsaturated triglycerides?
They are typically liquid at room temperature.
They primarily come from Plant sources (like Olive Oil).
Double bonds are reactive which makes them have lower stability and shelf lives.
What are examples of Mono and Poly unsaturated fats?
Mono = Olive Oil, Canola Oil
Poly = Corn Oil, Sunflower Oil
How can unsaturated fats be turned into saturated fats?
They could be converted into ‘Saturated’ fats through a process called hydrogenation.
Essentially, Hydrogen gets added to the molecule which gets ride of the double bond and makes it behave like a saturated fat.
This is seen in things such as Margarine which is incredibly unhealthy.
What are Phospholipids?
Phospholipids are what cell membranes are comprised of. They have a Hydrophilic, Polar phosphate head and hydrophobic, non-polar tails.
What is the structure of a Phospholipid?
It has a Glycerol backbone with two fatty acid groups and one phosphate group attached.
What are sterols?
They are essentially 4 linked carbon rings with sidechains.
They are the natural components of a cell membrane.
They are used by cells to make hormones, vitamin D and bile.
What are the two types of Cholesterol?
LDL: low density lipoprotein
HDL: high density lipoprotein
Lipids don’t dissolve well in water so for them to get around the blood stream they bind to proteins and make lipoproteins
What is the unhealthy lipoprotein?
LDL. You want higher HDL if possible.
LDL contributes to plaques on the walls of arteries which reduces blood flow and can cause cardiovascular issues in the future.
What does HDL do?
it is the ‘good’ cholesterol.
HDL transports cholesterol and other lipids back to the liver for proper disposal.
What are some food sources of Cholesterol?
Eggs, meats and Dairy (not skim).
