Lecture 7 - Lipids Flashcards
What are the 3 main types of lipids
Triglycerides
Phospholipids
Sterols
What lipid group makes up 90-95% of the lipids we consume?
Triglycerides
What are the 4 important structural parts that make up a triglyceride?
- Glycerol backbone
- 3 different fatty acid chains
- An acid group (COOH)
- Methyl group (CH3)
What are the 2 forms fatty acids can be in?
Saturated
Unsaturated
Why are the 3 fatty acid chains different?
They are composed of the materials that are present at the time. Whatever fatty acids are available will end up attached to the backbone
Are fatty acids organic?
Yes because it has C
How long can fatty acid chains be?
Length is dependent on how many C’s its composed of
Long (14-24)
Medium (6-12)
Short (Less than 6)
How long are most fatty acids that we consume?
Log chain
Why don’t we eat short chain fatty acids?
We can make them in our gut and then we can absorb them
What determines fatty acid digestion?
Chain length
What is a saturated fatty acid?
A chain fatty acid in which all C’s are filled with H’s
No double bonds
What is an unsaturated fatty acid?
A chain fatty acid which contains double bonds instead of H’s
What are the 2 types of unsaturated fatty acids?
Monosaturated
-1 double bond
Polysaturated
-2 or more double bonds
What do double bonds do to the fatty acid structure
Double bonds change the shape of the fatty acid, making it less stackable
What is a double bond technically called?
A kink
-changes the direction of the fatty acid
What will happen to lipids when it is completely saturated?
They are more likely to be solid at room temp because there are no kinks in the conformation, making the triglycerides more stackable. Therefore there is less room for the lipids to move
What will happen to lipids when it is unsaturated?
The kink from the double bond will change the direction of the rest of the chain, making more room for the 3 chains tome around. Lipid is more likely to be liquid at room temp.
How do you identify the location of a double bond?
The C in the methyl group is Omega 1 C, then the next C would be 2 and so on.
Can you switch an Omega 3 fatty acid to an Omega 6 fatty acid?
No, they are completely different families.
You can add H’s and double bonds to them, but they can not change families
What are the 2 essential fatty acids?
Linoleic acid
Alpha Linolenic acid
Which family is linoleic acid from, and what is its chemical name?
Omega 6
18: 2n-6
- shortest 6 in their family
Which family is alpha linolenic acid from, and what is its chemical name?
Omega 3
18: 3n-3
- shortest 3 in their family
What happens when we eat the essential fatty acids?
Linoleic acid is converted into AA
Alpha Linolenic acid is converted into EPA and DHA
What is the function of AA EPA and DHA?
All converted molecules are involved in cell signalling with opposing effects (6 vs. 3)
Act as hormones as cell signalling agents in a localized area
All have different effects so we need to balance these
How are triglycerides formed?
Condensation reactions
Glycerol+3Fatty Acids= Triglyceride + H2O
What are the 3 categories that oils fall into?
Saturated Fat
Monosaturated
Polysaturated
- characterized by how much of each group it has.
- all oils are a mix of the 3