The document summarizes the structure of DNA. It discusses that DNA is composed of phosphoric acid, deoxyribose sugar, and four nitrogenous bases. These components form nucleotides that bond together via phosphodiester bonds to create two polynucleotide strands that coil around each other to form the signature double helix structure of DNA. The structure allows DNA to efficiently store and replicate genetic information in organisms.
Introduction
History
Definition
Classification of DNA Polymerase
Mechanism of DNA Replication
Process of DNA Replication
Initiation
Regulation
Termination
Conclusion
Reference
DNA replication is semi-conservative, one strand serves as the template for the second strand. Furthermore, DNA replication only occurs at a specific step in the cell cycle.
DNA replication in eukaryotes is much more complicated than in prokaryotes, although there are many similar aspects.
DNA replication is a biological process that occurs in all living organisms and copies their DNA; it is the basis for biological inheritance.
Eukaryotic cells can only initiate DNA replication at a specific point in the cell cycle, the beginning of S phase.
Due to the size of chromosomes in eukaryotes, eukaryotic chromosomes contain multiple origins of replication
Introduction
Defination
What is damage?
Mutation
Types of mutation
Sources of damage
1.Endogenous
2.Exogenous
Types of damage
Common Carcinogen
Conclusion
Reference
DNA
INTRODUCTION
CHEMICAL COMPOSITION
NUCLEOSIDES & NUCLEOTIDES
DNA REPAIR
INTRODUCTION
TYPES OF DNA REPAIR
I)DIRECT REPAIR SYSTEM,
II)BASE EXCISION REPAIR,
III)NUCLEOTIDE EXCISION REPAIR,
IV)MISMATCH REPAIR,
V)RECOMBINATION REPAIR,
DEFECTS IN DNA REPAIR UNDERLIE HUMAN DISEASE
DNA RECOMBINATION
INTRODUCTION
MECHANISM OF DNA RECOMBINATION
TYPES OF RECOMBINATION
I) HOMOLOGOUS RECOMBINATION
MODELS FOR HOMOLOGOUS RECOMBINATION:-
I)HOLLIDAY MODEL,
II)MESSELSON AND RADDING MODEL,
III)DOUBLE STRAND BREAK MODEL,
GENE CONVERSION
II) NON-HOMOLOGOUS RECOMBINATION,
i) SITE SPECIFIC RECOMBINATION,
ii)TRANSPOSITIONAL RECOMBINATION.,
This power point presentation explains double helical structure of DNA as proposed by Watson and Crick (1953).Attempts have also been made to high light the valuable contributions made by Rosalind Franklin and Wilkins. Brief details of different types of DNA have also been included.
Introduction
History
Definition
Classification of DNA Polymerase
Mechanism of DNA Replication
Process of DNA Replication
Initiation
Regulation
Termination
Conclusion
Reference
DNA replication is semi-conservative, one strand serves as the template for the second strand. Furthermore, DNA replication only occurs at a specific step in the cell cycle.
DNA replication in eukaryotes is much more complicated than in prokaryotes, although there are many similar aspects.
DNA replication is a biological process that occurs in all living organisms and copies their DNA; it is the basis for biological inheritance.
Eukaryotic cells can only initiate DNA replication at a specific point in the cell cycle, the beginning of S phase.
Due to the size of chromosomes in eukaryotes, eukaryotic chromosomes contain multiple origins of replication
Introduction
Defination
What is damage?
Mutation
Types of mutation
Sources of damage
1.Endogenous
2.Exogenous
Types of damage
Common Carcinogen
Conclusion
Reference
DNA
INTRODUCTION
CHEMICAL COMPOSITION
NUCLEOSIDES & NUCLEOTIDES
DNA REPAIR
INTRODUCTION
TYPES OF DNA REPAIR
I)DIRECT REPAIR SYSTEM,
II)BASE EXCISION REPAIR,
III)NUCLEOTIDE EXCISION REPAIR,
IV)MISMATCH REPAIR,
V)RECOMBINATION REPAIR,
DEFECTS IN DNA REPAIR UNDERLIE HUMAN DISEASE
DNA RECOMBINATION
INTRODUCTION
MECHANISM OF DNA RECOMBINATION
TYPES OF RECOMBINATION
I) HOMOLOGOUS RECOMBINATION
MODELS FOR HOMOLOGOUS RECOMBINATION:-
I)HOLLIDAY MODEL,
II)MESSELSON AND RADDING MODEL,
III)DOUBLE STRAND BREAK MODEL,
GENE CONVERSION
II) NON-HOMOLOGOUS RECOMBINATION,
i) SITE SPECIFIC RECOMBINATION,
ii)TRANSPOSITIONAL RECOMBINATION.,
This power point presentation explains double helical structure of DNA as proposed by Watson and Crick (1953).Attempts have also been made to high light the valuable contributions made by Rosalind Franklin and Wilkins. Brief details of different types of DNA have also been included.
Introduction
Nucleic Acid Sequencing
Types of Nucleic Acid Sequencing
DNA Sequencing
Method of DNA Sequencing
Applications of DNA Sequencing
Conclusion
References
There are slides about DNA replication and types of DNA.
Here we study about different enzymes of replication and its process.Places of enzyme action also shown in the slides.Different proteins are also discussed.
Hello everyone, I am Dr. Ujwalkumar Trivedi, Head of Biotechnology Department at Marwadi University Rajkot. I teach Molecular Biology to the students of M.Sc. Microbiology and Biotechnology.
The current presentation is about the process of transcription in eukaryotes. The presentation describes the structure of various eukaryotic RNA polymerase promoters. The later part of the presentation gives a detailed insight into the mechanism of transcription of RNA Pol II genes and summarizes the post-transcriptional modification of mRNA.
In this slideshare, we know about the DNA supercoiling. How does it forms, size of DNA in a human body. How the chromosomes are formed. Useful enzymes that regulate the coiling of DNA. Relaxing stage of DNA which is circular form the left handed and right handed DNA coiling. Mostly in our body left handed coiling DNA are found. Importance of coiling their function and little bit of the structure of Supercoiling.
Introduction
Nucleic Acid Sequencing
Types of Nucleic Acid Sequencing
DNA Sequencing
Method of DNA Sequencing
Applications of DNA Sequencing
Conclusion
References
There are slides about DNA replication and types of DNA.
Here we study about different enzymes of replication and its process.Places of enzyme action also shown in the slides.Different proteins are also discussed.
Hello everyone, I am Dr. Ujwalkumar Trivedi, Head of Biotechnology Department at Marwadi University Rajkot. I teach Molecular Biology to the students of M.Sc. Microbiology and Biotechnology.
The current presentation is about the process of transcription in eukaryotes. The presentation describes the structure of various eukaryotic RNA polymerase promoters. The later part of the presentation gives a detailed insight into the mechanism of transcription of RNA Pol II genes and summarizes the post-transcriptional modification of mRNA.
In this slideshare, we know about the DNA supercoiling. How does it forms, size of DNA in a human body. How the chromosomes are formed. Useful enzymes that regulate the coiling of DNA. Relaxing stage of DNA which is circular form the left handed and right handed DNA coiling. Mostly in our body left handed coiling DNA are found. Importance of coiling their function and little bit of the structure of Supercoiling.
What are nucleic acidsWhy are these molecules so important to liv.pdfdeepakarora871
What are nucleic acids?
Why are these molecules so important to living organisms?
What are the basic structures of DNA and RNA? How are they similar? How are they different?
Solution
1.
Nucleic acids are the biopolymers or the molecules that allow the transfer of genetic material
from one generation to another generation.
These large biomolecules are necessary to all known forms of life.
The nucleic acids consists of nucleotides monomers linked together. Nucleotides consists of
nitrogenous base, five carbon sugar, phosphate group.
Nucleotides are linked together to form polynucleotide chains.
These are linked by a covalent bond and the linkage is between the phosphate and sugar
molecule and the linkage is called the phosphodiester linkage.
They are two types of nucleic acids they are DNA (deoxyribonucleic acid ) and RNA
(ribonucleic acid ).
Phosphodiester linkage forms the phosphate sugar backbone of both DNA and RNA.
2. DNA contains the instructions for the performance of all cell functions.
DNA is a genetic material and it is organized into the chromosome and it is found in the nucleus
of the cell and it is copied from one generation to another generation.
RNA is essential for synthesis of proteins . The information contained within the genetic code is
passed from DNA to RNA and they results in the formation of proteins.
3. DNA is a double helical structure and it consists of purines and pyramidines which are four
nitrogen bases like adenine, guanine , cytosine and thymine and phosphate -deoxyribose sugar
backbone.
In a double stranded DNA adenine pairs with thymine and guanine pairs with cytosine.
RNA is a single stranded molecule . It consists of phosphate ribose sugar backbone and the
nitrogenous bases like adenine ,guanine ,cytosine and uracil.
In RNA strand, adenine pairs with uracil and guanine pairs with cytosine. The nitrogen bases get
bonded to each other by hydrogen bonds.
The DNA and RNA are similar in having three nitrogenous bases like adenine, guanine and
cytosine and they are also similar in phosphate group.
They are different in nitrogen base like in DNA ,they have thymine as nitrogen base and in RNA
, they have uracil. In DNA ,they contain the five carbon sugar as deoxyribose and in RNA , the
five carbon sugar as ribose sugar.RNA is single stranded and DNA is double stranded..
Chap-7 Nucleic acid Power point presentationMegersa4
Nucleic acids
Get their name because they were first found in the nucleus of cells, but they have since been discovered also to exist outside the nucleus (cytoplasm).
Are the molecules within a cell that are responsible for ability to produce exact replicas of themselves. It is called ‘molecules of heredity’.
Are the principle genetic materials of all living organisms.
It contains C, H, O, N (10%) and P (15%).
Are condensation polymers of nucleotides.
Are the polynucleotides having high molecular weight.
It is a polymer in which the monomer units are nucleotides.
Nucleotides: Phosphoric acid esters of nucleosides.
Nucleotides = nucleoside + phosphate
Nucleotides are carbon ring structures containing nitrogen linked to a 5-carbon sugar.
5-carbon sugar is either a ribose or a deoxy-ribose making the nucleotide either a ribonucleotide or a deoxyribonucleotide.
Nucleosides are compounds in which nitrogenous bases (purines and pyrimidines) are conjugated to the pentose sugars (ribose or deoxyribose) by a β-glycosidic linkage.
Ribose (RNA) is a sugar, like glucose, but with only five carbon atoms in its molecule.
Deoxyribose (DNA) is almost the same but lacks one oxygen atom.
In both types of nucleotides the pentoses exist in their ß-furanose (closed five-membered ring) forms.
Both molecules may be represented by the symbol:
Despite the complexity and diversity of life the structure of DNA is dependent on only 4 different nucleotides.
Diversity is dependent on the nucleotide sequence.
All nucleotides are 2 ring structures composed of:
Despite the complexity and diversity of life the structure of DNA is dependent on only 4 different nucleotides.
Diversity is dependent on the nucleotide sequence.
All nucleotides are 2 ring structures composed of:
A nucleoside consists of a nitrogen base linked by a glycosidic bond to C1’ of a ribose or deoxyribose.
Nucleosides are named by changing the nitrogen base ending to -osine for purines and –idine for pyrimidines
A nucleotide is a nucleoside that forms a phosphate ester with the C5’ OH group of ribose or deoxyribose
Nucleotides are named using the name of the nucleoside followed by 5’-monophosphate
Biochemistry of nucleic acids DNA RNA structures with the comparison chart between them chemistry of nucleic acids structures and composition and protein synthesis nucleotides and nucleosides
DNA and RNA molecules are linear polymers built from individual units called nucleotides connected by bonds called phosphodiester linkages. DNA and RNA are used to store and pass genetic information from one generation to the next.
Lymphocyte is a type of white blood cell in the immune system of jawed vertebrate. Lymphocytes include natural killer cells (which function in cell-mediated, cytotoxic innate immunity), T cells (for cell-mediated, cytotoxic adaptive immunity), and B cells (for humoral, antibody-driven adaptive immunity). They are the main type of cell found in lymph, which prompted the name "lymphocyte". Th all myeloid and lymphoid cells develop from one type of stem cell called as Hematopoietic stem cell is a undifferentiated cell give rise to further diffetentiation of all the immune cell as well as blood cells include the T- cell and B-cell. The B-cell is synthesis and matured in the Bone Marrow and T- cell is synthesis in Bone marrow but matured in the thymus. In this topic will be discussed how the B-cell and T-cell are developed
GENOMIC MAPPING:FISH(Fluorescent in situ hybridization )UTTARAN MODHUKALYA
Genomic mapping is a graphic representation of the arrangement of genes or DNA sequences on chromosome & used to identify and record the location of gene & distances between genes on chromosome.
There are mainly two kinds of genome maps are known : 1.Genetic or linkage maps & 2. Physical maps
Where Physical map provides detail of the actual physical distance between genetic markers, as well as the exact location of genes.
An example of Physical mapping is FISH. FISH is a powerful technique for detecting RNA or DNA sequences in cells, tissues & tumors
Different type of immunologic cells are involved against pathogen......here about different types of immolune system cell are showing on the basis of their origin and function
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
2. We are very much pleased to submit our seminar
topic on Structure of DNA for B.Sc. 2nd semester. We
sincerely thanks to our honorable principal Dr.
Prasanna Kr. Dutta to give us opportunity for
preparing the seminar topic and our Professors
Dr.Indira Baruah (HOD), Dr.Gayatri Agni Bora and
Dr.Bikramaditya Bakalial of Zoology department of
our college for guiding properly the same.
We are also thankful to our other respected teachers
of the department and our friends and parents for
supporting us and help to make the seminar on the
above topic.
3. Introduction
Discovery of DNA
Chemical composition of DNA
Phosphoric Acid
Pentose Sugar
Nitrogenous Base
Structure of DNA formed by three
main components
Position of DNA in the chromosome
Arrangement of DNA duplex
Double helical structure of DNA
Conclusion
Reference
4. DNA is the genetic materials of all organisms
which is present in chromosome bind with
histone protein. DNA has two polynucleotide
chain which form a helical structure. The main
chemical components of the DNA are
phosphoric acid, deoxyribose sugar and four
different types of nitrogenous bases. The
phosphoric acid bind with the sugar by ester
bond, sugar-base bond is glycosidic bond
and bases are bound by hydrogen bond.
These are the basic component that form the
complete DNA structure.
5. F. Miesher separate
DNA from nucleus in
1869.In 1889
Altmann gives the
term nucleic acid.
Watson and Crick
proposed the
acceptable DNA
double helix model
that can explain the
specificity and
replicablity of the
gene.
7. It may occur also
phosphate and forms the
backbone of DNA
molecule along with
sugar molecule. It links
the nucleotide by joining
the deoxyribose sugar of
two adjacent nucleotide
with an ester phosphate
bond. This bond connect
3prime carbon in one
nucleotide with 5prime
carbon in next.
8. Deoxyribose sugar is
the pentose sugar
bearing C5H10O4
chemical formula
.The structure of
pentose sugar is
pentagonal ring
where 3 prime and 5
prime carbon atom
attached to
phosphoric acid and
in 1 prime carbon
atom to the base .
9. It is of two types -
1.Purine
2.Pyrimidine
1.Purine :- It
compose of Adenine
and Guanine with two
heterocyclic ring and
contain C,H,O and N
atoms .
10. 2.Pyrimidine :–
Mainly cytosine and
thymine are the
base present in
DNA with single
heterocyclic ring .
11. In case of DNA the ribose sugar’s 1prime C join to the
base through glycosidic bond and this compound is
known as nucleoside .When the 5prime C is joined with
phosphoric acid by ester bond then the whole compound
is known as nucleotide. The deoxyribonucleotide joined
by phosphodiester bond and form a strand .Since DNA is
double helix so, It has two strand .The another strand
run in opposite or antiparallel direction i.e. if one strand
is 3 prime to 5prime end forward direction then the
another one is 5 prime to 3 prime end in backward
direction. The two strand is joined by hydrogen bond
between two nitrogenous base. The adenine always
forms two numbers of bond with thymine and cytosine
forms three bond with guanine base.
15. The diameter of DNA
is 20Ǻ. Distance of
major groove is 22Ǻ
and minor groove is
12Ǻ. The distance of
two base pair is 3.4Ǻ.
The diameter of
pyrimidine base is
3.3Ǻ and purine is
4.7Ǻ.
16. From the above discussion we can
concluded that DNA has the double
helix that having two polynucleotide
chain coiled with each other .We
discuss about B-form DNA in the
above topic .
17. 1. Textbook of medical biochemistry
2. A K Berry
3. Trueman elementary biology
4. Internet
