Chapter #1 Biological Molecules Biology XI
Q1: Explain Terpenoids and its types.
Ans: Terpenoids:
Terpenoid is a large and important class of lipids, made up of
isoprenoid units (C5H8). Terpenes, steroids, carotenoids and
prostaglandins are type of Terpenoids. These are found in cell
membrane as cholesterol, as pigment like chlorophyll, fragrance as menthol etc.
Terpenes:
Terpens are the type of terpenoids which contain few isoprenoid units like dterpens,
Triterpens. These small size terpens are volatile in nature and produce special fragrance.
Some of these are used in perfume e.g., Myrcens from oil of bay, Geranoil from rose,
Limonene from lemon oil, Menthol from Peppermint oil.
Steroids:
Steroids is a type of Terpenoid which form steroid nucleus made up hrenoid units contain 17
Carbon atoms arranged in four attached rings, three them are hexagonal and one is
pentagonal in shape. The radical attached with them as side chains distinguish them from one
another. Cholesterol is one of the type of steroid. Cholesterol is the precursor for the
synthesis of a number of steroids i.e., testosterone, progesterone and estrogens.
Q2: What are lipids explain acylglycerol and waxes.
Ans: LIPIDS:
Lipids are the important diverse group of biological molecules, widely distributed among
plants and animals. The term lipid is proposed by Bloor in 1943, for those biomolecules
which are insoluble in water and soluble in organic solvents like ether and alcohol etc. These
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0300-0868403
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, Chapter #1 Biological Molecules Biology XI
compounds are made up of C, H, O like carbohydrates but contain much lesser ratio of
oxygen than carbohydrates e.g., stearin is a fat, has molecular formula (C57H11006).
Acylglycerol (Fats and oil):
These are the condensation product of glycerol and three fatty acid. Commonly called fats
and oils. They can be defined as the esters of glycerol and fatty acid. Ester is the bond or
linkage formed between alcohol and organic acid by removing water, this reaction is called
esterification.
Glycerol is a trihydroxy alcohol, made of three carbon atom each contain on OH- group,
while a fatty acid is a type of organic acid containing one carboxylic acid group with long
hydrocarbon chain. When three fatty acid combine with glycerol each at one -OH, they form
three ester bonds. A compound called Triglycerol (triglyceride) is formed. There are two
types of acylglycerol.
(a)Saturated acylglycerol (Fats)
They contain saturated fatty acid i.e., do not contain any double bond between carbon atoms
of hydrocarbon chain e.g., stearin.
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0300-0868403
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Q1: Explain Terpenoids and its types.
Ans: Terpenoids:
Terpenoid is a large and important class of lipids, made up of
isoprenoid units (C5H8). Terpenes, steroids, carotenoids and
prostaglandins are type of Terpenoids. These are found in cell
membrane as cholesterol, as pigment like chlorophyll, fragrance as menthol etc.
Terpenes:
Terpens are the type of terpenoids which contain few isoprenoid units like dterpens,
Triterpens. These small size terpens are volatile in nature and produce special fragrance.
Some of these are used in perfume e.g., Myrcens from oil of bay, Geranoil from rose,
Limonene from lemon oil, Menthol from Peppermint oil.
Steroids:
Steroids is a type of Terpenoid which form steroid nucleus made up hrenoid units contain 17
Carbon atoms arranged in four attached rings, three them are hexagonal and one is
pentagonal in shape. The radical attached with them as side chains distinguish them from one
another. Cholesterol is one of the type of steroid. Cholesterol is the precursor for the
synthesis of a number of steroids i.e., testosterone, progesterone and estrogens.
Q2: What are lipids explain acylglycerol and waxes.
Ans: LIPIDS:
Lipids are the important diverse group of biological molecules, widely distributed among
plants and animals. The term lipid is proposed by Bloor in 1943, for those biomolecules
which are insoluble in water and soluble in organic solvents like ether and alcohol etc. These
Prepared by Sheharyar Shoukat
0300-0868403
Page 1
, Chapter #1 Biological Molecules Biology XI
compounds are made up of C, H, O like carbohydrates but contain much lesser ratio of
oxygen than carbohydrates e.g., stearin is a fat, has molecular formula (C57H11006).
Acylglycerol (Fats and oil):
These are the condensation product of glycerol and three fatty acid. Commonly called fats
and oils. They can be defined as the esters of glycerol and fatty acid. Ester is the bond or
linkage formed between alcohol and organic acid by removing water, this reaction is called
esterification.
Glycerol is a trihydroxy alcohol, made of three carbon atom each contain on OH- group,
while a fatty acid is a type of organic acid containing one carboxylic acid group with long
hydrocarbon chain. When three fatty acid combine with glycerol each at one -OH, they form
three ester bonds. A compound called Triglycerol (triglyceride) is formed. There are two
types of acylglycerol.
(a)Saturated acylglycerol (Fats)
They contain saturated fatty acid i.e., do not contain any double bond between carbon atoms
of hydrocarbon chain e.g., stearin.
Prepared by Sheharyar Shoukat
0300-0868403
Page 2
