L18 - Lipid Structure and Function 1 Flashcards
1
Q
Are lipids polar?
A
No - they are soluble in non-polar solvents, not water
2
Q
if carbons are on the same side of the C=C bond, what is this called?
A
cis = the normal configuration in non-sat FAs
3
Q
Give the shorthand for double bonds, and melting point for each:
a) Oleic acid
b) Linoleic acid
c) a-Linolenic acid
A
a) DB = 18:1 on 9, MP = 16.0
b) DB = 18:2 on 9 and 12, MP = -5.0
c) DB = 18:3 on 9, 12 and 15 MP = -11.0
4
Q
If a saponification value is high what does this mean?
A
a high proportion of short FAs
- this is because there are more molecules per gram, and each molecule requires KOH to split the FAs away from it, therefore you need more KOH and a higher value
5
Q
If an iodine number of a fat what does this mean?
A
A high proportion of unsaturated fatty acid
1 molecule adds to a double bond
