This pdf is about the structure of ribosomes.
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General overview of Plasma/ Cell membrane.
Definition of Plasma/ Cell membrane
Structure of Plasma membrane
1. Sandwitch model ORDanielli- Davson Model
2. Fluid mosaic model
Plasma Membrane Proteins
Chemical Composition of Plasma/ Cell Membrane
Movement across the Cell Membrane
Channels through cell membrane
General overview of Plasma/ Cell membrane.
Definition of Plasma/ Cell membrane
Structure of Plasma membrane
1. Sandwitch model ORDanielli- Davson Model
2. Fluid mosaic model
Plasma Membrane Proteins
Chemical Composition of Plasma/ Cell Membrane
Movement across the Cell Membrane
Channels through cell membrane
RECOMBINATION MOLECULAR BIOLOGY PPT UPDATED new.pptxSabahat Ali
This ppt is about recombination and where it occurs. Types of recombination and models of recombination along with many factors in prokaryotic and eukaryotic recombination
Gel electrophoresis native, denaturing&reducingLovnish Thakur
Electrophoresis is a technique used to separate and sometimes purify macromolecules - especially proteins and nucleic acids - that differ in size, charge or conformation.
Definition - Rolling circle replication is a process of unidirectional nucleic acid replication.
* can rapidly synthesize multiple copies of circular molecules of DNA or RNA, such as plasmids.
* Eucaryotic also replicate.
* widely used in molecular biology & biomedical
nanotechnology, especially in the field of
biosensing (as a method of signal Amplification).
Steps:
Circular ds DNA will be “nicked”
3` end is elongated →Leading strand
5` end displaced → Lagging strand
made up of double stranded by OKAZAKI fragments.
4) Replication of both “ unnicked” and displaced ss DNA
5) Displaced DNA circulates and synthesis its own complementary strand.
Initation-- phosphate ends, by the action of:
a) Helicase
b) Topoisomerases
c) Single stranded binding proteins(SSBPs)
Elongation-OH group of broken strand, using the unbroken strand as a template. The polymerase will start to move in a circle for elongation, due to which it is named as Rolling Circle Model.
end will be displaced and will grow out like a waving thread.
Termination-* At the point of termination, the linear DNA molecule is cleaved from the circle resulting in a double stranded circular DNA molecule and a single- stranded linear DNA molecule.
* The linear single stranded molecule is circularized by the action of ligase and then replication to double stranded circular plasmid molecule.
Example- Conjugation of F+ and F- bacteria
Diagrammatic representation of Rolling circle
some Examples-Viral DNA
* Human herpes virus
* Human papilloma virus
* Geminivirus
Viral RNA
* pospiviridiae
* Avsunviridiae
Reference:- https://en. m. wikipedia.org
what- when- how.com
https//www.sciencedirect.com
www.slideshare.com
Genetics-notes.wikispace.com
you tube
Prescott 5th edition page.no: 236, 237
Brock biology of microorganism , page.no: 253,616
Prokaryotic and eukaryotic gene structurestusharamodugu
Organization of genome in Prokaryotes:
The term prokaryote means “primitive nucleus”. Cell in prokaryotes have no nucleus. The prokaryotic chromosome is dispersed within the cell and is not enclosed by a separate membrane. Much of the information about the structure of DNA comes from studies of prokaryotes, because they are less complex than eukaryotes. Prokaryotes are monoploids they have only one set of genes (one copy of the genome). In most viruses and prokaryotes, the single set of genes is stored in a single chromosome (single molecule either RNA or DNA).
Organization of genome in Prokaryotes:
The term prokaryote means “primitive nucleus”. Cell in prokaryotes have no nucleus. The prokaryotic chromosome is dispersed within the cell and is not enclosed by a separate membrane. Much of the information about the structure of DNA comes from studies of prokaryotes, because they are less complex than eukaryotes. Prokaryotes are monoploids they have only one set of genes (one copy of the genome). In most viruses and prokaryotes, the single set of genes is stored in a single chromosome (single molecule either RNA or DNA). Organization of genome in Prokaryotes:
The term prokaryote means “primitive nucleus”. Cell in prokaryotes have no nucleus. The prokaryotic chromosome is dispersed within the cell and is not enclosed by a separate membrane. Much of the information about the structure of DNA comes from studies of prokaryotes, because they are less complex than eukaryotes. Prokaryotes are monoploids they have only one set of genes (one copy of the genome). In most viruses and prokaryotes, the single set of genes is stored in a single chromosome (single molecule either RNA or DNA).
Transcription in eukaryotes: A brief view
Transcription is the process by which single stranded RNA is synthesized by double stranded DNA. Transcription in eukaryotes and prokaryotes has many similarities while at the same time both showing their individual characteristics due to the differences in organization. RNA Polymerase (RNAP or RNA Pol) is different in prokaryotes and eukaryotes. Coupled transcription is seen in prokaryotes but not in Eukaryotes. In eukaryotes the pre-RNA should be spliced first to be translated.
In Eukaryotic transcription, synthesis of RNA occurs in the 3’→5’ direction. The 3’ end is more reactive due to the hydroxide group. 5’ end containing phosphate groups meanwhile, is not very reactive when it comes to adding new nucleotides. In Eukaryotes, the whole genome is not transcribed at once. Only a part of the genome is transcribed which also acts as the first, principle stage of genetic regulation.
Eukaryotes have five nuclear polymerases:
• RNA Polymerase I: This produces rRNA (23S, 5.8S, and 18S) which are the major components in a ribosome. This also produces pre-rRNA in yeasts.
• RNA Polymerase II: Helps in the production of mRNA (messenger RNA), snRNA (small, nuclear RNA), miRNA. This is the most studied type and requires several transcription factors for its binding
• RNA Polymerase III: This synthesizes tRNA (transfer RNA), 5S rRNA and other small RNAs required in the cytosol and nucleus.
• RNA Polymerase IV: Synthesizes siRNA (small interfering RNA) in plants.
• RNA Polymerase V: This is the least studied polymerase and synthesizes siRNA-directed heterochromatin in plants.
Eukaryotic transcription can be broadly divided into 4 stages:
• Pre-Initiation
• Initiation
• Elongation
• Termination
Transcription is an elaborate process which cells use to copy the genetic information stored in DNA into RNA. This pre-RNA is modified into mRNA before being transcribed to proteins. Transcription is the first step to utilizing the genetic information in a cell. Both Eukaryotes and Prokaryotes employ this process with the basic phases remaining the same. However eukaryotic transcription is more complex indicating the changes transcription has undergone towards perfection during evolution.
RECOMBINATION MOLECULAR BIOLOGY PPT UPDATED new.pptxSabahat Ali
This ppt is about recombination and where it occurs. Types of recombination and models of recombination along with many factors in prokaryotic and eukaryotic recombination
Gel electrophoresis native, denaturing&reducingLovnish Thakur
Electrophoresis is a technique used to separate and sometimes purify macromolecules - especially proteins and nucleic acids - that differ in size, charge or conformation.
Definition - Rolling circle replication is a process of unidirectional nucleic acid replication.
* can rapidly synthesize multiple copies of circular molecules of DNA or RNA, such as plasmids.
* Eucaryotic also replicate.
* widely used in molecular biology & biomedical
nanotechnology, especially in the field of
biosensing (as a method of signal Amplification).
Steps:
Circular ds DNA will be “nicked”
3` end is elongated →Leading strand
5` end displaced → Lagging strand
made up of double stranded by OKAZAKI fragments.
4) Replication of both “ unnicked” and displaced ss DNA
5) Displaced DNA circulates and synthesis its own complementary strand.
Initation-- phosphate ends, by the action of:
a) Helicase
b) Topoisomerases
c) Single stranded binding proteins(SSBPs)
Elongation-OH group of broken strand, using the unbroken strand as a template. The polymerase will start to move in a circle for elongation, due to which it is named as Rolling Circle Model.
end will be displaced and will grow out like a waving thread.
Termination-* At the point of termination, the linear DNA molecule is cleaved from the circle resulting in a double stranded circular DNA molecule and a single- stranded linear DNA molecule.
* The linear single stranded molecule is circularized by the action of ligase and then replication to double stranded circular plasmid molecule.
Example- Conjugation of F+ and F- bacteria
Diagrammatic representation of Rolling circle
some Examples-Viral DNA
* Human herpes virus
* Human papilloma virus
* Geminivirus
Viral RNA
* pospiviridiae
* Avsunviridiae
Reference:- https://en. m. wikipedia.org
what- when- how.com
https//www.sciencedirect.com
www.slideshare.com
Genetics-notes.wikispace.com
you tube
Prescott 5th edition page.no: 236, 237
Brock biology of microorganism , page.no: 253,616
Prokaryotic and eukaryotic gene structurestusharamodugu
Organization of genome in Prokaryotes:
The term prokaryote means “primitive nucleus”. Cell in prokaryotes have no nucleus. The prokaryotic chromosome is dispersed within the cell and is not enclosed by a separate membrane. Much of the information about the structure of DNA comes from studies of prokaryotes, because they are less complex than eukaryotes. Prokaryotes are monoploids they have only one set of genes (one copy of the genome). In most viruses and prokaryotes, the single set of genes is stored in a single chromosome (single molecule either RNA or DNA).
Organization of genome in Prokaryotes:
The term prokaryote means “primitive nucleus”. Cell in prokaryotes have no nucleus. The prokaryotic chromosome is dispersed within the cell and is not enclosed by a separate membrane. Much of the information about the structure of DNA comes from studies of prokaryotes, because they are less complex than eukaryotes. Prokaryotes are monoploids they have only one set of genes (one copy of the genome). In most viruses and prokaryotes, the single set of genes is stored in a single chromosome (single molecule either RNA or DNA). Organization of genome in Prokaryotes:
The term prokaryote means “primitive nucleus”. Cell in prokaryotes have no nucleus. The prokaryotic chromosome is dispersed within the cell and is not enclosed by a separate membrane. Much of the information about the structure of DNA comes from studies of prokaryotes, because they are less complex than eukaryotes. Prokaryotes are monoploids they have only one set of genes (one copy of the genome). In most viruses and prokaryotes, the single set of genes is stored in a single chromosome (single molecule either RNA or DNA).
Transcription in eukaryotes: A brief view
Transcription is the process by which single stranded RNA is synthesized by double stranded DNA. Transcription in eukaryotes and prokaryotes has many similarities while at the same time both showing their individual characteristics due to the differences in organization. RNA Polymerase (RNAP or RNA Pol) is different in prokaryotes and eukaryotes. Coupled transcription is seen in prokaryotes but not in Eukaryotes. In eukaryotes the pre-RNA should be spliced first to be translated.
In Eukaryotic transcription, synthesis of RNA occurs in the 3’→5’ direction. The 3’ end is more reactive due to the hydroxide group. 5’ end containing phosphate groups meanwhile, is not very reactive when it comes to adding new nucleotides. In Eukaryotes, the whole genome is not transcribed at once. Only a part of the genome is transcribed which also acts as the first, principle stage of genetic regulation.
Eukaryotes have five nuclear polymerases:
• RNA Polymerase I: This produces rRNA (23S, 5.8S, and 18S) which are the major components in a ribosome. This also produces pre-rRNA in yeasts.
• RNA Polymerase II: Helps in the production of mRNA (messenger RNA), snRNA (small, nuclear RNA), miRNA. This is the most studied type and requires several transcription factors for its binding
• RNA Polymerase III: This synthesizes tRNA (transfer RNA), 5S rRNA and other small RNAs required in the cytosol and nucleus.
• RNA Polymerase IV: Synthesizes siRNA (small interfering RNA) in plants.
• RNA Polymerase V: This is the least studied polymerase and synthesizes siRNA-directed heterochromatin in plants.
Eukaryotic transcription can be broadly divided into 4 stages:
• Pre-Initiation
• Initiation
• Elongation
• Termination
Transcription is an elaborate process which cells use to copy the genetic information stored in DNA into RNA. This pre-RNA is modified into mRNA before being transcribed to proteins. Transcription is the first step to utilizing the genetic information in a cell. Both Eukaryotes and Prokaryotes employ this process with the basic phases remaining the same. However eukaryotic transcription is more complex indicating the changes transcription has undergone towards perfection during evolution.
Basics only
Ribosome’s are a cell structure that makes protein (seat of protein synthesis).
• Ribosomes are often referred as PROTEIN FACTORY of the cell.
• Protein is needed for many cell functions such as repairing damage or directing
chemical processes.
• The ribosome is a complex molecule made of ribosomal RNA molecules and
proteins that form a factory for protein synthesis in cells.
A ribosome is a complex cellular mechanism used to translate genetic code into chains of amino acids.
Long chains of amino acids fold and function as proteins in cells.
ultra structure of Ribosome, Prokaryotic Ribosome, Eukaryotic Ribosome, Svedberg unit, Centrifugal force, assembly of Ribosome, functions of Ribosome, models of Ribosomes, fine structure of Ribosome, Discovery of Ribosome,
Functionasites of ribosomes By KK Sahu SirKAUSHAL SAHU
INTRODUCTION
HISTORY
STRUCTURE
70s PROKARYOTIC RIBOSOMES
80s EUKARYOTIC RIBOSOME
CHEMICAL COMPOSITION
FUNCTIONAL SITES OF RIBOSOME
OVER VIEW OF PROTINE SYNTHESIS
FUNCTION
CONCLUSION
REFERENCE
THANKYOU
Ribosomes (from ribonucleic acid and Greek-”soma” meaning body) are complexes of RNA and proteins that are found in all cells.
Ribosomes are of basically two types- 70S and 80S.
The S refers to the Svedberg unit. This is a sedimentation coefficient which shows how fast a cell organelle sediment in an ultracentrifuge. The heavier the structure more is its sedimentation coefficient.
Ribosomes are the sites of protein synthesis in both prokaryotes and eukaryotes.
Ribosome is a non membrane cell organelles. it also know as protein factory of cell.. it was discovered by Emil Palade. It presents both in eukaryotes and prokaryotes. It has a major role in protein synthesis .
STRUCTURE & FUNCTION OF MAJOR ORGANELLES RIBOSOMES,LYSOSOMES,PEROXISOMES & EN...AJAYSOJITRA6
STRUCTURE AND FUCTION OF CELL ORGANELLES
INTRODUCTION:
While examining the animal and plant cell through a microscope, we might have seen numerous organelles that work together to complete the cell activities.
Aim: To study the effects of neurotoxins on the nervous system using photogra...SELF-EXPLANATORY
This pdf is about the Study of histopathological correlates of neurotoxicity using permanent slides/photographs.
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Insulin / Recombinant DNA Technique / Peptide HormoneSELF-EXPLANATORY
This pdf is about the Insulin / Recombinant DNA Technique / Peptide Hormone.
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This pdf is about the Fermentation Technology "Vinegar Production".
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This pdf is about the Cost of Assisted Reproductive Technology (Art).
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This pdf is about the Basal Lamina / Extracellular matrix / Base membrane.
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Chloride Channel / Ion Channels / Integral Membrane Proteins .pdfSELF-EXPLANATORY
This pdf is about the Chloride Channel / Ion Channels / Integral Membrane Proteins.
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This pdf is about the DNA Libraries / Genomic DNA vs cDNA.
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This pdf is about the Effect of Gut Microbiome on SCHIZOPHRENIA.
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This pdf is about the Schizophrenia.
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Behavioral Disorder: Schizophrenia & it's Case Study.pdfSELF-EXPLANATORY
This pdf is about the Behavioral Disorder: Schizophrenia & it's Case Study.
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Protein structure classification/domain prediction: SCOP and CATH (Bioinforma...SELF-EXPLANATORY
This pdf is about the protein structure classification/domain prediction: SCOP and CATH (Bioinformatics).
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This pdf is about the Guillain-Barré Syndrome (GBS).
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This pdf is about the Vulture Conservation.
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This pdf is about the Great Sparrow Campaign.
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This pdf is about the obesity.
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This pdf is about the different types of Energy Resources.
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This pdf is about the differences between REM & NON REM Sleep.
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This pdf is about the Positron Emission Tomography (PET) technique.
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Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Normal Labour/ Stages of Labour/ Mechanism of LabourWasim Ak
Normal labor is also termed spontaneous labor, defined as the natural physiological process through which the fetus, placenta, and membranes are expelled from the uterus through the birth canal at term (37 to 42 weeks
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
5. ▪ Ribosomes were first observed in the mid-1950s
by Romanian-American cell biologist George
Emil Palade, using an electron microscope, as
dense particles or granules.
▪ The term “ribosome” was proposed by scientist
Richard B. Roberts in the end of 1950s: while
examining the animal and plant cell through a
microscope, you might have seen numerous
organelles that work together to complete the cell
activities.
▪ One of the essential cell organelles are
ribosomes, which are in charge of protein
synthesis.
Discovery
6. Introduction
▪ The ribosome word is derived – ‘ribo’ from ribonucleic acid
and ‘somes’ from the Greek word ‘soma’ which means ‘body’.
▪ Ribosomes are tiny spheroidal dense particles (of 150 to 200 A°
diameters) that are primarily found in most prokaryotic and
eukaryotic.
▪ They are sites of protein synthesis.
▪ They are structures containing approximately equal amounts of
RNA and proteins and serve as a scaffold for the ordered
interaction of the numerous molecules involved in protein
synthesis.
▪ Ribosomes are organelles located inside the animal, human
cell, and plant cells.
▪ The ribosomes occur in cells, both prokaryotic and eukaryotic
cells.
▪ In prokaryotic cells, the ribosomes often occur freely in the
cytoplasm.
7. ▪ In eukaryotic cells, the ribosomes either occur freely in the
cytoplasm or remain attached to the outer surface of the
membrane of the endoplasmic reticulum.
▪ The location of the ribosomes in a cell determines what kind
of protein it makes.
▪ If the ribosomes are floating freely throughout the cell, it will
make proteins that will be utilized within the cell itself.
▪ When ribosomes are attached to the endoplasmic reticulum,
it is referred to as rough endoplasmic reticulum or rough
ER.
▪ Proteins made on the rough ER are used for usage inside the
cell or outside the cell.
▪ The number of ribosomes in a cell depends on the activity of
the cell.
▪ On average in a mammalian cell, there can be about 10
million ribosomes.
Introduction
8. ▪ A ribosome is made from complexes of
RNAs and proteins and is, therefore, a
ribonucleoprotein.
▪ Around 62% of ribosomes are
comprised of RNA, while the rest is
proteins.
▪ Each ribosome is divided into two
subunits:
▪ A smaller subunit which binds to a larger
subunit and the mRNA pattern, and
▪ A larger subunit which binds to the tRNA,
the amino acids, and the smaller
subunit.
Figure:StructureofRibosomes
9. ▪ Prokaryotes: have 70S ribosomes respectively subunits
comprising the little subunit of 30S and the bigger subunit of 50S.
▪ Their small subunit has a 16S RNA subunit (consisting of 1540
nucleotides) bound to 21 proteins.
▪ The large subunit is composed of a 5S RNA subunit (120
nucleotides), a 23S RNA subunit (2900 nucleotides) and 31 proteins.
▪ Eukaryotes: have 80S ribosomes respectively comprising of little
(40S) and substantial (60S) subunits.
▪ The smaller 40S ribosomal subunit is prolate ellipsoid in shape and
consists of one molecule of 18S ribosomal RNA (or rRNA) and 30
proteins (named as S1, S2, S3, and so on).
▪ The larger 60S ribosomal subunit is round in shape and contains a
channel through which growing polypeptide chain makes its exit.
▪ It consists of three types of rRNA molecules, i.e., 28S rRNA, 5.8
rRNA and 5S rRNA, and 40 proteins (named as L1, L2, L3 and so
on).
Figure:StructureofRibosomes
11. ▪ The differences between the ribosomes of bacterial and
eukaryotic are used to create antibiotics that can destroy
bacterial infection without harming human cells.
▪ The ribosomes seen in the chloroplasts of mitochondria of
eukaryotes are comprised of big and little subunits composed
of proteins inside a 70S particle.
▪ The ribosomes share a core structure that is similar to all
ribosomes despite differences in its size.
▪ The two subunits fit together and work as one to translate the
mRNA into a polypeptide chain during protein synthesis.
▪ Because they are formed from two subunits of non-equal size,
they are slightly longer in the axis than in diameter.
▪ During protein synthesis, when multiple ribosomes are
attached to the same mRNA strand, this structure is known
as polysome.
▪ The existence of ribosomes is temporary, after the synthesis of
polypeptide the two sub-units separate and are reused or
broken up.
Structure
of
Ribosomes
12. ▪ Ribosome contains three major active sites:
▪ aminoacyl (A) site – point of attachment of aa-loaded
tRNA
▪ peptidyl (P) site – point of attachment of tRNA
holding polypeptide
▪ exit E site – point where “unloaded” tRNA leaves the
ribosome
▪ In addition, there are there
▪ decoding center: located in the 30S subunit, this site
ensures proper codon/anticodon attachment. (A tRNA
matching a particular codon is called a cognate tRNA
with respect to that codon).
▪ peptidyl transferase center: located in the 50S
subunit, this active site catalyzes peptide bonds.
Figure: Structure of Ribosome
13. Functions of
Ribosomes
▪ The ribosome is a complex molecular machine, found within all living
cells, that serves as the site of biological protein synthesis
(translation).
▪ Ribosomes link amino acids together in the order specified by
messenger RNA (mRNA) molecules.
▪ Ribosomes act as catalysts in two extremely important biological
processes called peptidyl transfer and peptidyl hydrolysis.
▪ It assembles amino acid to form proteins that are essential to carry out
cellular functions.
▪ The DNA produces mRNA by the process of DNA transcription.
▪ The mRNA is synthesized in the nucleus and transported to the
cytoplasm for the process of protein synthesis.
▪ The ribosomal subunits in the cytoplasm are bound around mRNA
polymers.The tRNA then synthesizes proteins.
▪ The proteins synthesized in the cytoplasm are utilized in the cytoplasm
itself, the proteins synthesized by bound ribosomes are transported
outside the cell.
14. References
▪ Dr, lJ, Satyan arayana,Biochemistry 3rd Edition
▪ Jeremy M. Berg, John L Tymoczko, lubert Stryer, Biochemistry, 5th edition.
▪ https://microbenotes.com/ribosomes-structure-and-functions/
▪ https://byjus.com/biology/ribosomes/
▪ https://alevelbiology.co.uk/notes/ribosomes-structure-and-functions/
▪ https://biologydictionary.net/ribosome/
▪ http://www.bio.miami.edu/dana/250/250SS16_9.html
▪ https://useruploads.socratic.org/XYEERPSSHmBWIrcYdmQw_ribosom
e.jpg
▪ https://images.app.goo.gl/cPE5kfYQt8pVLkHR6