Pretend you are a teacher preparing a quiz for the text I will provide. 
            Each quiz question should follow the format below. 
            Ensure that you carefully recheck the questions and answers for accuracy. 
            The output should be a ready-to-use list of dictionaries for the Python eval function:

            [

                    "question": "WRITE THE QUESTION HERE",
                    "options": ["A) OPTION_1", "B) OPTION_2", "C) OPTION_3", "D) OPTION_4"],
                    "answer": INDEX_OF_CORRECT_ANSWER_IN_OPTIONS_LIST,
                    "explanation": "EXPLAIN WHY THE ANSWER IS CORRECT"

            ]

            Text:
            CH3(CH2)16COOH
20
Arachidic acid
Eicosanoic acid
CH3(CH2)18COOH
22
Behenic acid
D
o
c
B
o
i
o
s
c
h
a
e
n
m
i
o
s
t
r
i
y
c
f
o
a
r
m
c
e
i
d
d
i
c
s
C
6
/
H
2
9
/
2
(
0
C
1
2
H
 
 )
COOH
3
2 20
3. Derived Lipid
29 
Unsaturated fatty acids may further be divided as  follows-
(1)Monounsaturated (monoethenoid, monoenoic) acids,  containing 
one double bond.
(2) Polyunsaturated (polyethenoid, polyenoic) acids,
containing two or more double bonds.
The configuration of the double bonds in most  unsaturated 
fatty acids is cis.
The double bonds in polyunsaturated fatty acids are  separated by 
at least one methylene group.
Biochemistry for medics
6/29/2012
30
3. Derived Lipid
30 
3. Derived Lipid
31 
Polyunsaturated fatty acids such as Linoleic and  
Linolenic acids are essential for normal life  functions. 
They are therefore characterized as  essential fatty acids.
Arachidonic acid is considered as semi essential  fatty acid 
since it can be synthesized from  Linoleic acid .
Essential polyunsaturated fatty acids can be  classified as 
belonging to one of two "families",  the omega-6 family 
or the omega-3 family.
Fatty acids belonging to these two families  differ not only 
in their chemistry, but also in  their natural occurrence and 
biological functions.
3. Derived Lipid
32 
1.
They are useful in the treatment of atherosclerosis 
(transport & decrease blood cholesterol & TG).
2.
The hormones are synthesized from them.
3.
Enter in structure of all cellular & subcellular membranes  & 
transport plasma phospholipids.
4.
Essential for skin integrity, normal growth & reproduction.
5.
Play important role in blood clotting (intrinsic factor).
6.
Important in preventing & treating fatty liver.
7.
Important role in health of the retina & vision.
8.
Can be oxidized for energy production.
Function of Essential Fatty Acids
3. Derived Lipid
33 
Steroids constitute an important class  of 
biological compounds.
Usually found in association with fat.
They’re derivatives of cholesterol that is formed of
steroid ring or nucleus (C17).
Biologically important groups contain this ring, are:
1)
Sterols
2) Steroids
2)
Adrenal cortical hormones
3)
Male & female sex hormones
4)
Vitamin D
5)
Bile acids
6)
Cardiac glycosides
A
B
Steroid nucleus “4 C rings” (no FA)
3. Derived Lipid
34 
Sterols
2
3
10
5
4
6
8
7
12
17
HO
1
A
9
14
15
B
21
22
24
26
20
23
25
18
27
11
13
16
19
C
D
Cholesterol
CH3
CH3
CH3  
CH3
HO
CH3
Insoluble in water
Found in animals but not in vegetable &plants
Include: Cholesterol (animals), Ergosterol (fungi) & Sitosterol (plants)
a) Cholesterol (CHL):
The most abundant steroid in the body
(Cholesterol-3-hydroxy-5,6-cholesten)
1)
Biosynthesis of steroid  
hormones, vitamin D, cardiac  
glycosides,…..
2)
Important component of cell
membrane (free CHL is a minor
component of cell membrane)
3) Formation of the bile salts (from  
catabolism of CHL in the liver)
Cholesterol Function
3. Derived Lipid
35 
• Produced from oxidation of CHL in the liver
•


            Quiz: