Lecture 1: Intro to lipids Flashcards
Lipids are —– molecules that are highly soluble in organic solvents
water insoluble
5 Classes of lipids:
- Free fatty acids
- Triacyglycerols
- Phospholipids
- Glycolipids
- Steroids
What are free fatty acids for?
Fuel, building blocks for membrane lipids
What are triacylglycerols for?
Storage form of fatty acids
What are phospholids?
Fatty acids with a charged phosphoryl group
What are glycolipids
Lipids attached to carbohydrate
What are steroids?
Polycyclic hydrocarbons
Out of the 5 classes of lipids which are membrane lipids?
- Phospholipids
- Glycolipids
- Steroids
Fatty acid structure
Hydrocarbons with a terminal carboxylic acid groups
Palmitate fatty acid structure, systematic name
- 16 Carbons, no double bonds
- n-Hexadecanoate
- CH3(CH2)14COO-
Fatty acid naming conventions
- carbon 1 is at the carboxyl terminus
- Carbon 2 is called alpha
- Carbon 3 is called beta
- The last carbon is called omega (w)
- △ marks the position of a double bond
- Cis-△6 means there is a cis double bond between carbons 6 and 7
- Trans-△6 means there is a trans double bond between carbon 6 and 7
Stearate fatty acid structure, systematic name
- n-Octadecanoate
- 18 carbons, no double bond
- CH3(CH2)16COO-
Oleate fatty acid structure, systematic name
- 18 carbons, 1 double bond at carbon 9
Name this
What is the root names for 18 carbon fatty acid chain from no double bond to 4 double bond?
What is the systematic name, struture of a-linolenate
a-linolenate is also known as
- omega 3 fatty acid
What is the common name, systematic name and structure for laurate
- common name: Laurate
- Ch3(CH2)10COO-
- n-Dodecanoate
- 12 carbons, no double bonds
What is the common name, systematic name and structure for myristate
- common name: myristate
- 14 carbons no double bond
- n-Tetradecanoate
- ## CH3(CH2)12COO-
What is the common name, systematic name and structure for palmitoleate
- 16 carbons, 1 double bond at carbon 9
- cis-△9-Hexadecenoate
What is the common name, systematic name and structure for linoleate
-18 carbons, 2 double bonds
- cis, cis-△9, △12-Octadecadienoate
Draw me trans-Oleate
What is the chemical structure for Glycerol
Chemical structures for: phosphatidate (diacylglycerol 3-phosphate)
Chemical structures for: phosphatidylserine
Chemical structures for: phosphatidylcholine
Chemical structures for: phosphatidylethanolamine
Chemical structures for: diphosphatidylglycerol (cardiolipin)
Properties of fatty acids are dependent on: (2)
- Chain length (ex: 16, 18 or 20 carbons)
- Degree of saturation
Unsaturated fatty acids have a —- melting point then saturated fatty acids of the same length
- lower melting point
Shorter carbon chains have a —– than longer carbon chains
lower melting point
Van der waals interactions between hydrocarbon tails is distrupted by —–
cis double bonds
Talk about bacon fat
- lots of stearate (18:0)
- saturayed
- which is why it is solid at room temp
Talk about olive oil/vegetable oil
- oleate (FA with 18C and 1 double bond)
- liquid and not solid at RT so lower MT due to double bond
How is a triglyceride structured?
3 fatty acids esterified to a glycerol scaffold
Fatty acids in animals (4)
carbon atoms, config for DB
- even number of carbon atoms (12-20)
- 16 and 18 carbon fatty acids are most common
- The confirguration at double bonds is usually cis
- Double bonds in polyunsaturated fatty acids are seperated by at least 1 methylene -ch2- group
Triaglycerols are efficient form of stored energy because (3):
+compared to a carbohydrate?
- hydrophobic molecule that packs tightly
- fatty acids are highly reduced molecules (Lots of energy in bond and can be used by metabolizing)
- more energy per gram of triacyglycerol then a carbohydrate
