Prokaryotic DNA replication : These slides contains basics of the prokaryotic DNA replication for S.Y.B.Sc and T.Y.B.Sc students of Microbiology and biotechnology
It covers topics like Enzymes used in replication, Semiconservative replication, Meselson and Stahl experiment, Termination of replication, modes of replication: theta and rolling circle, basic rules of replication
Prokaryotic DNA replication : These slides contains basics of the prokaryotic DNA replication for S.Y.B.Sc and T.Y.B.Sc students of Microbiology and biotechnology
It covers topics like Enzymes used in replication, Semiconservative replication, Meselson and Stahl experiment, Termination of replication, modes of replication: theta and rolling circle, basic rules of replication
A powerpoint presentation for Mrs. Tabor's 7th grade science students. I have a FITB note sheet to accompany this presentation and would be happy to email it to you. Contact stabor@belgradeschools.com
Nucleic Acids
DNA
Eukaryotic Chromosomes
The Histones
Deoxynucleic acid ( DNA )
Importance of Nucleotides
Base pairing
Denaturation and Renaturation
Determination GC content
Prokaryotic DNA synthesis
Prokaryotic DNA Replication
Transcription
Coding Strand and Template Strand
Steps of RNA synthesize
DNA replication is the process by which DNA makes a copy of itself during cell division. In molecular biology, DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule. DNA replication occurs in all living organisms acting as the basis for biological inheritance.
Step 1: Replication Fork Formation. Before DNA can be replicated, the double stranded molecule must be “unzipped” into two single strands. ...
Step 2: Primer Binding. The leading strand is the simplest to replicate. ...
Step 3: Elongation. ...
Step 4: Termination.
According to the central dogma of molecular biology, genetic information usually flows (1) from DNA to DNA during its transmission from generation to generation and (2) from DNA to protein during its phenotypic expression in an organism
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.
Dna chemistry structure,fuctions and its orgainizationneha sheth
DNA, Nucleotides, Structure of DNA, Features of DNA, watson-crick Model of DNA,base pairing rule, Denaturation of DNA,Higher organization of DNA, Histones, chromosomes, nucleosomes, introns, extrons, repeat sequences of DNA
A powerpoint presentation for Mrs. Tabor's 7th grade science students. I have a FITB note sheet to accompany this presentation and would be happy to email it to you. Contact stabor@belgradeschools.com
Nucleic Acids
DNA
Eukaryotic Chromosomes
The Histones
Deoxynucleic acid ( DNA )
Importance of Nucleotides
Base pairing
Denaturation and Renaturation
Determination GC content
Prokaryotic DNA synthesis
Prokaryotic DNA Replication
Transcription
Coding Strand and Template Strand
Steps of RNA synthesize
DNA replication is the process by which DNA makes a copy of itself during cell division. In molecular biology, DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule. DNA replication occurs in all living organisms acting as the basis for biological inheritance.
Step 1: Replication Fork Formation. Before DNA can be replicated, the double stranded molecule must be “unzipped” into two single strands. ...
Step 2: Primer Binding. The leading strand is the simplest to replicate. ...
Step 3: Elongation. ...
Step 4: Termination.
According to the central dogma of molecular biology, genetic information usually flows (1) from DNA to DNA during its transmission from generation to generation and (2) from DNA to protein during its phenotypic expression in an organism
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.
Dna chemistry structure,fuctions and its orgainizationneha sheth
DNA, Nucleotides, Structure of DNA, Features of DNA, watson-crick Model of DNA,base pairing rule, Denaturation of DNA,Higher organization of DNA, Histones, chromosomes, nucleosomes, introns, extrons, repeat sequences of DNA
A detail ppt about Genome organization with focus on all levels of organization. Most recent research and findings about CT is also added in this ppt. Detail account of 30nm fiber and its ultra structure and types is also included.
DNA organization or Genetic makeup in Prokaryotic and Eukaryotic SystemsBir Bahadur Thapa
DNA organization or Genetic makeup in Prokaryotic and Eukaryotic Systems!! It is prepared under the syllabus of Tribhuwan University, Nepal, MSc. 3rd Semester as a lecture class!!
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
1. DNA structure determination
10/10/0533
• Franklin collected x-ray
diffraction data (early 1950s)
that indicated 2 periodicities
for DNA: 3.4 Å and 34 Å.
• Watson and Crick proposed a
3-D model accounting for the
data.
2. CELL STRUCTURE AND
BIOMOLECULES
Molecular biology- Energy based flow of
information from DNA to RNA to
proteins and enzymes i.e. from Hypo
pituitary access to hormones to
homeostatic etc.
3. The mother of all biomolecules
10/10/05
42
1ffk
Large subunit of the ribosome(proteins at least)
8. INACTIVE &ACTIVE CHROMATIN
• Active (transcriptionally active)differ
from from inactive region.
• DNA in active region contain large
regions(100,000bp)prone to digestion by
Dnase- I (single strand cut)
9. MAJOR AND MINOR
GROOVES
• MINOR
– EXPOSES EDGE FROM WHICH C1’ ATOMS
EXTEND
• MAJOR
– EXPOSES OPPOSITE EDGE OF BASE PAIR
• THE PATTERN OF H-BOND POSSIBILITIES IS
MORE SPECIFIC AND MORE
DISCRIMINATING IN THE MAJOR GROOVE
10.
11. DNA structure
10/10/05
34
Fig. 8-15
•DNA consists of two
helical chains wound
around the same axis in
a right-handed fashion
aligned in an antiparallel
fashion.
• There are 10.5 base pairs,
or 36 Å, per turn of the
helix.
• Alternating deoxyribose and
phosphate groups on the
backbone form the outside
of the helix.
• The planar purine and
pyrimidine bases of both
strands are stacked inside
the helix.
12.
13. Much of Genome is not
TRANSCRIBED
• The entire human haploid
genome contain sufficent DNA to
code for app. 1.5 million genes.
• Human genome encodes less
than 100,000 proteins ie 1% of
human genome.
• 24% of genome as Introns
14. More than half DNA of Eukaryotic is
non Repetitive Sequences.
• In humans 10,000 to 15000 . genes are
expressed.
• Different combination of genes are
expressed in each tissue,of course and
how this is accomplished in one of the
major unanswered question in biology.
15. 30% of Human Genome has
Repetitive sequences
• A.Highly repetitive: 5-500 bp length
repeated many times.(these seq. are
transcriptionaly inactive)may play role in
structure of ch.
• B. Moderately repetitive: 106
copies
per haploid genome are not clustered but
are interspred with unique seq.
• C. Microsatelite repeat seqs.2-6bp
repeated up to 50 times(AC=TG)AC
repeat seqs. Are50000-100000 locations
in genome.
16. TELOMERE
• The ends of each chromosome
contains structures called TELOMERES
• Telomere consist of short repeat TG
sequences.(5’-TTAGGG-3’)can run for
kb.
• TELOMERASE ( RNA+RNA dependent
DNA polymerasesor{ Reverse
transcriptase} is responsible for
telomere synthesis) & maintains length
of telomere.
17. Cont………………………….
• Genome of Prokaryotes are
circular.human &Eukaryotes is linear as
result the lagging strand has incomplete
51 end. Each round of replication would
shorten the chromosome.Telo=End.
• How are repeated sequences generated
the enzyme TELOMERASE performs this
function.
• The protein component of
telomerases,hence it acts as reverse
transcriptase.that carries its own template.
• Telomerase levels are raised in cancer
cells.
18. DNA
• Two helical polynucleotide chains
are coiled around a common axis.
• The chains run in opposite
directions.(Template and Coding)
• Sugar-Phosphate backbones are
on the outer side and Purine
&Pyrimidene bases lie on the
inside of helix.
• The bases are prepandicular to the
helix axis. (10 bases per turn of
Helix)
• Diameter of helix is 20 Ao.
19. Cont………………………..
• In between large regions there
are shorter streches (100-
300)which are more sensative
to Dnase-I These sites provides
a sight for transcription.
(euchromatin)
• Transcriptionally inactive ch. Is
densly packed.
(Hetrochromatin)
20. A-DNA
• RIGHT-HANDED HELIX
• WIDER AND FLATTER THAN B-DNA
• 11.6 BP PER TURN
• PITCH OF 34 A
AN AXIAL HOLE
• BASE PLANES ARE TILTED 20 DEGREES
WITH RESPECT TO HELICAL AXIS
– HELIX AXIS PASSES “ABOVE” MAJOR GROOVE
DEEP MAJOR AND SHALLOW MINOR
GROOVE
• OBSERVED UNDER DEHYDRATING
CONDITIONS
21. B-DNA
• B-DNA Right handed double helix.
• Supercoils store energy.
• Supercoiled DNA is prefered form.
• DNA of E.coli is1.4mm, 4.7million
bp.
• Eukaryotes contain more than ten
times of DNA as compaired to
prok.
22. Z-DNA
• A LEFT-HANDED HELIX
• SEEN IN CONDITIONS OF HIGH SALT
CONCENTRATIONS
– REDUCES REPULSIONS BETWEEN CLOSEST
PHOSPHATE GROUPS ON OPPOSITE
STRANDS (8 A VS 12 A IN B-DNA)
• IN COMPLEMENTARY POLYNUCLEOTIDES WITH
ALTERNATING PURINES AND PYRIMIDINES
– POLY d(GC) · POLY d(GC)
– POLY d(AC) ⋅ POLY d(GT)
• MIGHT ALSO BE SEEN IN DNA SEGMENTS WITH
ABOVE CHARACTERISTICS
23. B,A and Z DNA
10/10/0538
Fig. 8-19
• B form - The most common
conformation for DNA.
• A form - common for RNA
because of different sugar
pucker. Deeper minor groove,
shallow major groove
• A form is favored in conditions
of low water.
• Z form - narrow, deep minor
groove. Major groove hardly
existent. Can form for some
DNA sequences; requires
alternating syn and anti base
configurations.
36 base pairs
Backbone - blue;
Bases- gray
24. DNA strands
10/10/05
37
Fig. 8-16
• The antiparallel strands of DNA
are not identical, but are
complementary.
• This means that they are
positioned to align complementary
base pairs: C with G, and A with
T.
• So you can predict the sequence
of one strand given the sequence
of its complement.
• Useful for information storage
and transfer!
• Note sequence conventionally is
given from the 5' to 3' end
25. Discovering the structure of DNA
• DNA = Deoxyribose nucleic acid
• Made out of sugars (deoxyribose), phosphates
and nitrogen bases
26. Difference between
DNA and RNA
• Sugar: DNA;deoxyribose.
• RNA; Ribose.
• DNA: A,T,G,C.: RNA;A,U,G,C.
• DNA Double,RNA single stranded.
• DNA A=T,G=C, RNA; U=A,,G=C not.
• RNA can be hydrolysed by
Alkali,DNA not.
27. HISTONES:
• H1
• H2A
• H2B
• H3
• H4
Acetylation linked with replication,H1
with condensation,DNA
repair,transcription
repression,methylation of histones
activation and repression of gene.
28.
29.
30. HISTONES
• Most abundant basic chr.protein.
• H1Loosly bound to chr,¬ not
necessary,but adjecent nucleosome
is joined by H1, nucleosome
• Nucleosome contain four types of
histones.H2A,H2B,H3 and H4
• Function identical in all eukaryotes.
• Four core Histones are subject to 6
types of covalent modifications
32. The mother of all biomolecules
10/10/05
42
1ffk
Large subunit of the ribosome(proteins at least)
33. Z-DNA
• 12 (W-C) BASE PAIRS PER TURN
• A PITCH OF 44 DEGREES
• A DEEP MINOR GROOVE
• NO DISCERNIBLE MAJOR GROOVE
• REVERSIBLE CHANGE FROM B-DNA TO
Z-DNA IN LOCALIZED REGIONS MAY ACT
AS A “SWITCH” TO REGULATE GENE
EXPRESSION
– ? TRANSIENT FORMATION BEHIND
ACTIVELY TRAN-
SCRIBING RNA POLYMERASE
34. FORCES THAT STABILIZE
NUCLEIC ACID STRUCTURES
• SUGAR-PHOSPHATE CHAIN
CONFORMATIONS
• BASE PAIRING
• BASE-STACKING,HYDROPHOBIC
• IONIC INTERACTIONS
35. DNA TOPOLOGY
• THE TOPOLOGICAL PROPERTIES OF DNA HELP US
TO EXPLAIN
• DNA COMPACTING IN THE NUCLEUS
• UNWINDING OF DNA AT THE REPLICATION FORK
• FORMATION AND MAINTENANCE OF THE
TRANSCRIPTION BUBBLE
• MANAGING THE SUPERCOILING IN THE
ADVANCING TRANSCRIPTION BUBBLE
36.
37.
38.
39. mRNA (messenger RNA)
• mRNA is synthasized from DNA by
enzyme RNA Polymerase.
• Introns and Exons.(Hetrogenous
hnRNA)
• Most hetrogenous,highly elongated
and short lived.
• Has 5’—3’ polarity complimentary to
coding strand.
• For protein synthesis.
• Stable in Euk. Unstable in Pro.
40.
41.
42.
43. tRNA (Transfer RNA)
• Much smaller in size (75-90
ribonucleotide)Clover leaf shaped.
• 15% of total cellular RNA.
• 20 species of tRNA.
• It acts as adaptor molecule.
• 40 different tRNA.
• Five arms of tRNA: 1:D-Arm; 2:TUC-
Arm 3: CCA Arm(Acceptor) 4:
Anticodon Arm 5: Variable Arm or
Extra Arm (determine Sp.).
44. tRNA
• Amino Acid acceptor arm 7 base pair
stem
• 5’—3’ CCA.Links Amino Acid.AA are
linked co-valently to corresponding
tRNA by enz.AAtRNA Synthetase.
• Anticodon Arm Has 5-bp loop and
triplet nucleotide
sequence(anticodon) complimentary
to codon.
• DHU arm .3-4 base pairs.
• TUC arm stem has 5 bp.
45. RIBOSOMAL RNA
• Are present in Ribosomes in
association with many polypeptides.
• 80 % of total cellular RNA.
• Very complex in Euc. Two sub-units
(60S)and (40S)
• Protein Synthesis.
• Larger unit has 3 RNA ie 5S,5.8S,28S
with 50 polypeptides.
• Smaller subunit has 18S and 30
polypeptides.
46.
47.
48.
49.
50. MITOCHONDRIAL DNA
• 54 out of 67 genes are coded by
nuclear genes,rest are coded by
Mitochondria.(mt)
• It form 1% of total cellular DNA.
• It codes 13 proteins that play key role
in the respiratory chain.
51. Features of mtDNA
• Circular,double stranded
• Contains 16,569 bp
• Encodes 13 protein subunits.
• Encodes 22 mt. tRNA molecules.
• Encodes(16s) and a small (12s)mt rRNA
• Very few untranslated sequences.
• High mutation rate (5-10 times to nucl.)
• M for M (Maternaly inherited Mitochondria)
52. Discovering the structure of DNA
• DNA = Deoxyribose nucleic acid
• Made out of sugars (deoxyribose), phosphates
and nitrogen bases
53. The mother of all biomolecules
10/10/05
42
1ffk
Large subunit of the ribosome(proteins at least)