1.7 - Lipids Flashcards
How are lipids grouped together?
They are non-polar and hydrophobic
What are the 4 major groups of lipids?
1) triglycerides
2) phospolipids
3) sterols
4) waxes
What are triglyerides?
Oily fats stored in fat cells called adipocytes.
They are used for energy storage, insulation, and padding (protection and & shock absorption)
Describe the structure of triglycerides.
1 glycerol + 3 fatty acids (carboxylic acids) = triglyride + 3 H2O
They form ester bonds when connected
What are saturated fats?
Fatty acid chains that have only single bonds, have all hydrogens connected, and symmetrical & straight
What are un-saturated fats?
Fatty acid chains that are made of double & triple bonds, and missing hydrogens in some locations
What state of matter are saturated fats in, at room temperature?
They are solids
Molecues are close together
What state of matter are un-saturated fats in at room temperature?
They are liquids
B/c chains have bends and kinks due to double bonds
What does monosaturated mean?
One double bond present in fats
What does polysaturate mean?
more than one double bond present in fats
What is hydrogenation?
- This is the process where unsaturated fats react with hydrogen to “fill in the gaps”
- This causes the unsaturted fats to become more solid at room temp. Ex: margerine made with oilve oil
- Hydrogenation never fully satuates the fatty acid chains but can create trans-fats (fats in the trans position)
What are phosolipids?
Where is it most commonly used?
When a lipid is both hydrophilic and hydrophobic.
It’s most commonly used in cell mebranes.
What is the structure of a phosolipid?
1 triglycerol + 2 fatty acids (saturated or unsaturated) + 1 phosphate
- replace a fatty acid chain with a phosphate
What happens when phospholipids are placed in water?
What is this called?
From lipids and membranes sub-heading
They re-arrange themselves with the hydrophobic tails facing together (inwards) to avoid water, and the hydrophilic ends face the opposite direction.
This is called phospholipid bilayer.
What are sterols?
A type of lipid that are arranged into 4 rings.
Used in hormones and cholesterol (LDL & HDL)
