Molecular Basis of Inheritance PPT Biology Class 12

 Page 2


Introduction
• Name the two type of nucleic acid found in living organism.
Deoxyribonucleic acid (DNA) & Ribonucleic acid (RNA)
• What act as the genetic material in most of the living organism?
DNA
• In virus what act as the genetic material other than DNA?
RNA
• List some functions of RNA
Messenger, catalytic molecule
Page 3


Introduction
• Name the two type of nucleic acid found in living organism.
Deoxyribonucleic acid (DNA) & Ribonucleic acid (RNA)
• What act as the genetic material in most of the living organism?
DNA
• In virus what act as the genetic material other than DNA?
RNA
• List some functions of RNA
Messenger, catalytic molecule
• Nucleic acids.
• Nucleic acids are the macromolecules present in all living cell.
• Freidrich Miescher was the first person isolated the nucleic acids 
from the pus cells. He called it as nuclein.
• As it has an acidic nature, hence  Altmann called it as nucleic acids.
• The two types of nucleic acids found in living organisms are, 
1. Deoxyribonucleic acid [DNA]
2. Ribonucleic acid [RNA].
Page 4


Introduction
• Name the two type of nucleic acid found in living organism.
Deoxyribonucleic acid (DNA) & Ribonucleic acid (RNA)
• What act as the genetic material in most of the living organism?
DNA
• In virus what act as the genetic material other than DNA?
RNA
• List some functions of RNA
Messenger, catalytic molecule
• Nucleic acids.
• Nucleic acids are the macromolecules present in all living cell.
• Freidrich Miescher was the first person isolated the nucleic acids 
from the pus cells. He called it as nuclein.
• As it has an acidic nature, hence  Altmann called it as nucleic acids.
• The two types of nucleic acids found in living organisms are, 
1. Deoxyribonucleic acid [DNA]
2. Ribonucleic acid [RNA].
Deoxyribonucleic acid [DNA]
• Genetic material of all living organisms- carries the coded information 
from one generation to another generation.
• In eukaryotic cell DNA is found nucleus. It is the chief component of 
chromosomes. 
• DNA also found in the mitochondria and chloroplasts
• Long polymer of deoxyribonucleotides.
• Length of the DNA - number of nucleotides or pair of nucleotide (base 
pairs)
• Eg. Bacteriophage- ? 174- 5386 nucleotides, Bacteriophage lambda-
48502 base pair (bp), human DNA- 3.3 X 10
9 
bp.
Page 5


Introduction
• Name the two type of nucleic acid found in living organism.
Deoxyribonucleic acid (DNA) & Ribonucleic acid (RNA)
• What act as the genetic material in most of the living organism?
DNA
• In virus what act as the genetic material other than DNA?
RNA
• List some functions of RNA
Messenger, catalytic molecule
• Nucleic acids.
• Nucleic acids are the macromolecules present in all living cell.
• Freidrich Miescher was the first person isolated the nucleic acids 
from the pus cells. He called it as nuclein.
• As it has an acidic nature, hence  Altmann called it as nucleic acids.
• The two types of nucleic acids found in living organisms are, 
1. Deoxyribonucleic acid [DNA]
2. Ribonucleic acid [RNA].
Deoxyribonucleic acid [DNA]
• Genetic material of all living organisms- carries the coded information 
from one generation to another generation.
• In eukaryotic cell DNA is found nucleus. It is the chief component of 
chromosomes. 
• DNA also found in the mitochondria and chloroplasts
• Long polymer of deoxyribonucleotides.
• Length of the DNA - number of nucleotides or pair of nucleotide (base 
pairs)
• Eg. Bacteriophage- ? 174- 5386 nucleotides, Bacteriophage lambda-
48502 base pair (bp), human DNA- 3.3 X 10
9 
bp.
• DNA & RNA - polynucleotide chain
• A nucleotide – 3 components
1. A nitrogenous base
2. A pentose sugar (DNA- deoxyribose sugar, RNA- Ribose sugar)
3. A phosphate group
• Nitrogenous base- Nitrogen containing compound
• Two types- Purines (Adenine & Guanine) & Pyrimidines (Cytosine, Uracil 
& Thymine)
• Adenine, Guanine & Cytosine- Both DNA & RNA
• Thymine- only in DNA
• Uracil- Only in RNA in place of Thymine
• Nitrogenous Base linked is linked to pentose sugar through N- glycosidic
linkage- Nucleoside
Structure of polynucleotide chain