glycosidic linkage
The two monosaccharides are joined together by an
oxide linkage formed by the loss of a water molecule. Such a linkage
between two monosaccharide units through oxygen atom is called
glycosidic linkage.
invert sugar
- Sucrose is dextrorotatory but after hydrolysis gives
dextrorotatory glucose and laevorotatory fructose. - Since the
laevorotation of fructose (–92.4°) is more than dextrorotation of
glucose (+ 52.5°), the mixture is laevorotatory. - Thus, hydrolysis of
sucrose brings about a change in the sign of rotation, from dextro
(+) to laevo (–) and the product is named as invert sugar.
maltose comprises of
two
alpha-D-glucose units
lactose (milk sugar)
composed of beta-D-galactose and beta-D-glucose
starch is found in
cereals, roots, tubers and some vegetables.
starch is a polymer of
alpha glucose
glycogen is present in
liver, muscles and brain
and in yeast and fungi
importance of carbohydrates.
- Carbohydrates are used as storage molecules as starch in
plants and glycogen in animals. - Cell wall of bacteria and plants is
made up of cellulose. - We build furniture, etc. from cellulose in the form of wood and clothe ourselves with cellulose in the form of cotton fibre. They provide raw materials for many important industries like textiles,
paper, lacquers and breweries.
Two aldopentoses ___________ are present in nucleic acids.
D-ribose and 2-deoxy-D-ribose
peptide linkage
Chemically, peptide linkage is an amide formed between–COOH group and –NH2
group. The reaction between two molecules of
similar or different amino acids, proceeds through
the combination of the amino group of one molecule
with the carboxyl group of the other. This results in
the elimination of a water molecule and formation of
a peptide bond –CO–NH–.
complete hydrolysis of dna (or rna) produces
Complete hydrolysis of DNA (or RNA) yields a pentose sugar, phosphoric
acid and nitrogen containing heterocyclic compounds (called bases).
In
DNA molecules, the sugar moiety is -D-2-deoxyribose whereas in
RNA molecule, it is -D-ribose.
vitamins
They are generally regarded as organic compounds
required in the diet in small amounts to perform specific
biological functions for normal maintenance of optimum growth and health of the organism.
nucleoside
A unit formed by the attachment of a base to 1 position of sugar is
known as nucleoside.
nucleotide
when nucleoside is linked to phosphoric acid 5th position of sugar moiety is called nucleotide
Nucleotides are joined together by ___________between
5 and 3 carbon atoms of the pentose sugar.
phosphodiester linkage
DNA fingerprinting is now used
(i) in forensic laboratories for identification of criminals.
(ii) to determine paternity of an individual.
(iii) to identify the dead bodies in any accident by comparing the DNA’s of parents or
children.
(iv) to identify racial groups to rewrite biological evolution.
The two strands in DNA are not identical but are complementary. Explain.
Two
nucleic acid chains are wound about each other and held together
by hydrogen bonds between pairs of bases. The two strands are
complementary to each other because the hydrogen bonds are
formed between specific pairs of bases. Adenine forms hydrogen
bonds with thymine whereas cytosine forms hydrogen bonds
with guanine.
primary structure of nucleic acids
Information regarding the sequence of nucleotides in the chain
of a nucleic acid is called its primary structure.
Nucleic acids
secondary structure
double strand helix structure for DNA
Two
nucleic acid chains are wound about each other and held together
by hydrogen bonds between pairs of bases.
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Electrochemistry 110
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Electrochemistry 211
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Electrochemistry 36
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Electrochemistry-43
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Coordination compounds 19
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Coordination Compounds-219
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Applications of coordination compounds6
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Aldehydes and ketones definition10
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Applications of aldehydes13
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chemical kinetics12
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chemical kinetics 20
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coordination compound 311
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coordination compound 413
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complementary colours7
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vitamins9
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vitamins - diseases9
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biomolecules19
