...Describe how proteins are synthesized Protein synthesis is extremely important for the survival of cells. This process is tightly regulated in order to ensure protein production is properly controlled. Assembly of a protein occurs in several steps, however the two major processes can be outlined as transcription and translation.1 Before understanding the details of how proteins are synthesized, one needs to understand the general notions of DNA. DNA is found within a cell’s nucleus, and protein synthesis occurs in the cytoplasm; therefore genetic information must be transferred from the nucleus to the cell. The first step of protein synthesis is transcription, which involves the formation of messenger RNA (mRNA) from DNA. mRNA holds information about a specific gene which will be carried out of the nucleus. mRNA is single stranded and is the template for protein synthesis. mRNA is simply a complementary copy of one of the strands of the DNA double helix that encodes for a specific protein.2 Transcription can be divided into three main steps: initiation, elongation, and termination. To initiate transcription, the enzyme RNA polymerase binds to a promoter sequence on the DNA strand.3 As a result, the binding causes the double stranded DNA to denature, revealing the template strand and formation of a transcription bubble. mRNA is synthesized within this transcription bubble through the addition of ribonucleotides complementary to the DNA template strand by RNA polymerase....
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...of Structure in Nucleic Acids Primary (1o) Structure – order of bases in the polynucleotide sequence Secondary (2o) Structure – 3D conformation of backbone Tertiary (3o) Structure – supercoiling of the molecule Quaternary (4o) Structure – interaction between DNA & proteins Two principle types of nucleic acids - DNA (deoxyribonucleic acid) - RNA (ribonucleic acid) How do DNA and RNA differ? Ribosomes: polypeptide-generating machinery of the cell Tobacco mosaic virus: nucleic acid strand winds through a cylinder of coat-protein subunits 9.2 The Covalent Structure of Polynucleotides Nucleotides: monomers of nucleic acids 1. Nitrogenous base 2. Sugar 3. Phosphoric acid residue Order of nucleic acids of DNA contains the information necessary to produce the correct amino acid sequence in the cell’s proteins What are the structures and components of the nucleotides? Nucleic acid bases (nucleobases): one or two-ring nitrogenous aromatic compound - Pyrimidines – single-ring aromatic compounds Cytosine – DNA & RNA Thymine – substitute for Uracil in DNA (sometimes in RNA) Uracil – RNA only - Purines – double-ring aromatic compounds Adenine – DNA & RNA Guanine – DNA & RNA Methylation can modify bases Nucleoside - base + sugar covalently bonded - lacks phosphate group - base forms a glycosidic linkage with sugar Ribonucleoside: β-D-ribose Deoxyribonucleoside: β-D-deoxyribose The glycosidic linkage is from C-1’ carbon...
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...1. Write an essay on protein structure and synthesis Protein synthesis is a cellular process leading to the production of proteins. This term is also synonymous to protein translation. It begins with a sequential process of transcription of DNA into mRNA, which is then used as input for translation after exon-intron splicing. The addition of successive tRNA molecules based on the code of mRNA matched up by base-pairing through their anti-codons in the ribosomes creates the nascent protein. After the protein chain has been synthesized, post-translation modification occurs, e.g. phosphorylation, motifs added to the protein. This may happen at various levels: secondary (alpha-helix, beta-sheets, turn, random coiling), tertiary and quarternary. Protein synthesis is also the process wherein peptide bonds between two amino acids whose formation is controlled. The synthesis begun when the mRNA combines in a little subunit of ribosomes close to an AUG sequence in mRNA. Start codon which is the AUG codon is being such because it does the coding of the first amino acid to be made of protein. “The AUG codon base-pairs with the anticodon of tRNA carrying methionine. A large ribosomal subunit binds to the complex, and the reactions of protein synthesis itself can begin. The aminoacyl-tRNA to be called for next is determined by the next codon (the next three bases) on the mRNA. Each amino acid is coded for by one or more (up to six) codons” (Center for Bioenergy and Photosynthesis...
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...Protein synthesis is used by mRNA to carry coded information for the sequence of amino acids in proteins. mRNA carries the coded information for the group of proteins from the DNA to the ribosomes. Protein synthesis and how each of the medications inhibits help understand which infections are treated by which medications. The Ciprofaxacin stops the protein synthesis, stops the recoiling, it is a g+ bacteria & allows the antibiotic in to kill bacteria bc of the peptidoglycan layer permeability. This antibiotic has some side effects to the host bc of the cell wall damage, nausea, vomiting, diarrhea & rash are the most common. Erythromycin is a antibiotic that is used for the g- bacteria & binds to the front of Asite of 50S subunit of ribosome of susceptible bacteria & suppresses protein synthesis. This is due to the role of the ribosomes in protein synthesis as they are released from the DNA. The codons allow for a certain amount of protein alteration & when this is near completion, the antibiotic disrupts the molecule before it starts all over again. The effects that this drug will have on the hosts cells are nausea, vomiting, diarrhea, hepatotoxicity, seizures & rash at iv site bc of the damage to the cell walls. With the Acyclovir, the protein synthesis is interrupted in a virally infected cell. It blocks the DNA synthesis by thymidine & alters & converts the acyclovir. The acyclovir doesn’t have any effect on a cell wall that isn’t infected by a virus so it won’t affect the...
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...Protein Synthesis Protein synthesis is the process in which protein is made. The first part of protein synthesis is transcription. Transcription is the process if transcribing genetic information from DNA to RNA and it occurs inside the nucleus. DNA has four nitrogenous bases (adenine (A), guanine (G), cytosine (C) and thymine (T) that are paired together as A-T and G-C. Since DNA is a double helix the second strand has the corresponding nitrogenous bases. The second base has the complementary pairs to the nitrogenous bases of the nucleotides in the first strand. During the process of protein synthesis, DNA helicase unwinds or unzips the double helix of DNA creating two separate strands. An enzyme called RNA polymerase, which bind the RNA nucleotides to the DNA strand bases using complementary pairing, then binds to the strand of DNA and waits for a starter signal to start transcribing the DNA. This forms mRNA (messenger RNA) which is the newly transcribed RNA from the DNA and the mRNA is then transported out of the nucleus into the cytoplasm. Now the mRNA must be translated to protein. This happens in a process called translation. The initiation codon of the process of translation is AUG (adenine, uracil, and guanine). During translation tRNA turns the sequence of nitrogenous bases into codons. A codon is a sequence of three nitrogenous bases. The codons create amino acids which the tRNA carries to ribosomes in the cell. The ribosome is what actually constructs protein synthesis...
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... synthesizing. E. using energy. 4. Which of the following is NOT a characteristic function of a cell? A. reproduction and inheritance B. metabolism and energy use C. movement D. synthesis E. communication 5. Which of the following could be used to study general features of cells? A. a magnifying glass B. scanning electron microscope C. transmission electron microscope D. binoculars E. light microscope 6. In order to study in detail the anatomy of internal cell parts, it would be best to use A. x-rays. B. flashlights. C. a transmission electron microscope (TEM). D. tissue cultures. E. a scanning electron microscope (SEM). 7. The plasma membrane A. separates the nucleus from the rest of the cell. B. is a rigid protein membrane. C. is not permeable. D. has a single layer of phospholipids. E. regulates movement of materials into and out of the cell. 8. The environment outside the plasma membrane is most appropriately referred to as A. intracellular. B. extracellular. C. multicellular. D. centrocellular. E. None of these choices is correct. 9. Glycolipids would contain both lipids and A. carbohydrates. B. proteins. C. electrolytes. D. cholesterol. E. amino acids. 10. The main components of the plasma membrane are A. carbohydrates and lipids. B. lipids and ions. C. proteins and carbohydrates. D....
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...Material DNA Worksheet Answer the following in at least 100 words: 1. Describe the structure of DNA. A DNA molecule which is abbreviation for deoxyribonucleic acid is made up of very long chains of monomers and polymers that are called nucleotides. These two chains in particular which composes of DNA strain are then formed by the grouping of the nucleotides into the polynucleotides. The nucleotide is made up of a nitrogenous base, of sugar and of a phosphate group. In the DNA case, there are four nucleotides that are found along the DNA chain, the four nucleotides ate (T) thyme, (A) adenine, (C) cytosine, and (G) guanine. These four nucleotides are joined together by their covalent bonds, or more specific, the phosphates and the sugar which composes the sugar/phosphate back bone of the polynucleotide. 2. How does an organism’s genotype determine its phenotype? The genotype of an organism is the genetic makeup of that organism, it is the nucleotide bases in the organism’s DNA. The phenotype is considered the physical traits of the organism which comes from the actions of the broad variety of proteins. The body of an organism is made up by the structural proteins and the metabolic activities are catalyzed by the enzymes. The synthesis of the proteins is specified by the DNA. However, a protein is not directly built by a gene, but dispatches the instructions to do so in the form of the RNA, which in turn programs the synthesis of the protein. ...
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...following terms: chromatin, chromosomes, DNA, gene. DNA, CHROMOSOMES AND GENES 2. What is a polynucleotide? 3. Diagram a typical nucleotide and name the three principle parts. COMPOSITION OF NUCLEIC ACIDS 4. Nucleosides differ from nucleotides in what way? 5. There are five Nitrogen bases in nucleic acids. Name them and group them according to their structure. Which of the five bases is found only in RNA and which base does it substitute? 6. Draw a ribose and a deoxyribose sugar side-by-side and highlight what makes them different. Identify the carbon atoms in your diagrams by their proper number. NUCLEOSIDES 7. Summarize the differences between DNA and RNA. NUCLEOTIDES 8. Between what two atoms do ester bonds occur? 9. What types of bonds join individual nucleotides WITHIN a single DNA strand? 10. What does the term "antiparallel" mean when applied to a DNA double helix? Why is this term necessary? 1. Draw a normal ladder and compare it to the structure of DNA. THE STRUCTURE OF NUCLEIC ACID CHAINS 12. What force holds the two halves of the DNA double helix together? 13. Explain what is meant by "Complementary Base Pairing" and don't forget to mention the numbers of hydrogen bonds involved! THE WATSON-CRICK MODEL: BASE PAIRING IN DNA 14. Diagram and explain the Central Dogma of Molecular Genetics. NUCLEIC ACIDS AND HEREDITY 15. Explain how DNA is replicated including all relevant enzymes and other terms. 16. How does the DNA polymerase "know" which base needs to be...
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...The Process of DNA Replication Western Governors University The Process Of DNA Replication The process of DNA replication at the biochemistry level starts with DNA to RNA and RNA to protein. DNA is “The Master” molecule of every cell. It contains vital information that is passed onto every generation. It has information on how to make itself as well as other molecules. DNA is the key to life. RNA leaves the nucleus of the cell and makes proteins. (Sally Seller December 2013) http:/ /www.cytochemistry.net/cell-biology/ ribosome.htm The process by which both strands are replicated starts with the strands being separated and unwound by DNA Helicase. DNA polymerases, an enzymes which catalyze the synthesis of new complementary strands will add nucleotides to the 3’ end of the growing nucleotide strand. An RNA primer is needed to start the synthesis of a new strand to make the first 3’ end the enzyme needs. After that, the RNA is taken out and replace with DNA. The synthesis of both complementary strands start in the 5’ to 3’ direction. The leading strand will then grow continuously in the direction of the replication fork. On the leading strand, RNA primase comes in and add RNA primer. ! ! (thinkwell biochemistry 6.4.2) Newly synthesized DNA The lagging strand will point away from the opening of the fork. RNA primase will constantly add RNA primer as the strand opens up On the leading strand, DNA polymerase III will work to add all the DNA nucleotide . On...
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... Deoxyribonucleic acid or DNA is found in basically all organisms including humans. It is the hereditary material that basically every person has and is found in both the cell nucleus and the mitochondria. Most of a person’s DNA is nuclear DNA because it is found in the nucleus; small portions of DNA can also be found in the mitochondria, giving this type the name mtDNA or mitochondrial DNA. DNA has many properties; one of its most important is that it can copy itself. When this process occurs, the double helix strands of DNA are used as a pattern for replicating the base sequences. This is crucial during cell division due to the imperative need for each new cell to carry a precise copy of the DNA found in the old cell. Adenine (A), thymine (T), guanine (G), cytosine (C) and uracil (U) are five out of about three billion chemical bases that store DNA’s coded information; over 99% of these bases have been found to be consistent in all people. The sequence of the bases is extremely important because the order that they are found in, reveals the information necessary and accessible for creating and upholding an organism. A simple way to comprehend this explanation is that DNA works in similar ways to alphabet letters; letters are put in certain orders to form a word or sentence and if they were to be mixed up, they would have a much different meaning. DNA is composed of two long strands that form a spiral made up of nucleotides called...
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...generations. This process of replication is universal for all the different types of cells. The genome constitutes the complete store of information of an organism and it specifies all the ribonucleic acid (RNA) molecules and proteins that the organism will ever synthesize, through the processes of transcription and translation, respectively. All the genetic information is encrypted...
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...DNA & RNA DNA Replication is semi conservative; meaning each strand of DNA is a template for new strands of DNA. DNA helicase is an enzyme that starts the process of DNA replication by opening the double helix stranded unwinding it. The Single stranded binding protein helps prevent DNA from attaching during the replication process( Hudon-Miller, 2013). DNA polymerase III is an enzyme that produces new strand, only reads in the 3’ to 5’ and adds new DNA strand in the 5’ to 3’ direction by forming replication bubbles and attaching at each replication fork. Because it can only add nucleotides to the 3’ direction there would be 2 different kinds of replication stands. The leading strand would be continuous towards the replication fork needing 1 RNA primer to initiate synthesis and the lagging strand would be fragmented away from the replication fork needing RNA primer to synthesize multiple times. Once RNA primer completes synthesis in the new DNA strand, DNA polymerase I fills the fragments with new nucleotides. DNA ligase is part of the last step of DNA. Its enzymes seal the Okazaki fragments together in creating a new DNA strand (Ahern & Rajogopal). In order to create new proteins for our bodies to perform its functions, DNA would have to go through a process called Transcription. Transcription is a process in which DNA is copied by mRNA. This takes place in the nucleus of the cell.DNA uses the help of RNA polymerase II which is an enzyme that initiates the synthesis...
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...Program Material DNA Worksheet Answer the following in at least 100 words: 1. Describe the structure of DNA. The three-dimensional structure of DNA – the double helix – arises from the chemical and structural feature of its two polynucleotide chains. Because these two chains are held together by hydrogen bonding between the bases on the different strands, all the bases are on the inside of the double helix, and the sugar-phosphate backbones are on the outside. In each case, a bulkier two ring base is paired with a single-ring base; A always pairs with T, and G with C. In this arrangement, each base pair is similar width, thus holding the sugar-phosphate backbones an equal distance apart along the DNA molecule. To maximize the efficiency of base-pair packing, the two sugar-phosphate backbones wind around each other to form a double helix, with one complete turn every ten base pairs. 2. How does an organism’s genotype determine its phenotype? An organism’s genotype, its genetic makeup, is the sequence of nucleotide bases in its DNA. The phenotype, the organism’s physical traits, arises from the actions of a wide variety of proteins. Structural proteins help make up the body of an organism, and enzymes catalyze its metabolic activities. DNA specifies the synthesis of proteins. However, a gene does not build a protein directly, but rather dispatches instructions in the form of RNA, which in turn programs protein synthesis. This molecular chain...
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...DNA Replication Jennifer Wilson Biochemistry GRT1 Margie Hayes January 18,2015 Deoxyribonucleic Acid (DNA) DNA is made of chemical building blocks called nucleotides. These building blocks (nucleotides) are made of phosphate, sugar and one of four types of nitrogen bases. The four types of nitrogen bases found in nucleotides are: adenine, thymine, guanine and cytosine. These nucleotides are either purine or pyrimidine based, called nucleotide subunits. The purine base are adenine and guanine. The pyrimidine based are thymine and cytosine. The DNA strand is formed when the nucleotides are linked into chains, with the phosphate and sugar group alternating. As you can see in the diagram above, adenine bonds with thymine and guanine bonds with cytosine. These bonds take place by hydrogen bonding. DNA Replication Fork Topoisomerases are enzymes that regulate the overwinding or underwinding of DNA, shown as the yellow wire above. Topoisomerases catalyze and guide the unknotting and unkinking of DNA. The double-helical configuration that DNA strands naturally reside makes them difficult to separate, so they must be separated by helicase enzymes. Helicase separates the strands of a DNA double helix by using the energy from ATP hydrolysis so replication can begin. The replication bubble allows replication to take place in 2 directions. Primase is an enzyme that synthesizes short RNA sequences called primers. These primers are the starting point for DNA synthesis at...
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...CITY AND ISLINGTON COLLEGE Assignment BriefFront Cover Centre: | Centre for Applied Sciences | | | Learner name: | Mohamed elrraik | | | Course Code: | AS2212A11/AS2211A11 | | | Programme Level &Title: | BTEC Level 3 Extended Diploma in Applied Science | | | Unit Number & Title: | Unit 18 Genetics & Genetic Engineering | | | Assignment Title: | Assignment 1 – DNA & Protein synthesis | | | Assessor Name: | Jasmin Bongrani | | | Date Issued: | AS2212A11 12/09/11AS2211A11 30/01/12 | DateDue: | AS2212A11 10/10/11AS2211A11 05/03/12 | | | | | Turn It In Score: | | Referral Due Date: | | | | | | Internal Verifier Name: | Lee Walker | Date IVed: | 08/09/11 | Grading criteria | Y/N | Feedback(including action where necessary) | P1 | Compare and contrast the structure of various nucleic acids | | | M1 | Explain how genetic information an be stored in a sequence of nitrogenous bases in DNA | | | D1 | Explain the steps involved in biosynthesis of protein including the roles of RNA | | | Additional Feedback and/or Action Plan: Date marked: | | Learner Declaration | I declare that all the work submitted for this assignment is my own work or, in the case of group work,the work of myself and the other members of the group in which I worked, and that no part of it has beencopied from any source. I understand that if any part of the...
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