list the 3 basic steps of dna replication

The three steps in the process of DNA replication are initiation, elongation and termination. Step by step Solved in 2 steps See solution Check out a sample Q&A here Half of the parent DNA molecule is conserved in each of the two daughter DNA molecules. On the other hand, the telomerase genes are active in normal dividing cells (e.g., stem cells) and cancer cells, which contain abundant telomerase. Grey indicates the original DNA strands, and blue indicates newly synthesized DNA. There is no attached model, but the greatest discoveryin biologyin 1953 could be only the discovery of DNA double helix. G At the most basic level, different sections of DNA strands (sequences of nitrogenous bases) provide instructions for the synthesis of proteins. DNA polymerase III is the main enzyme that then elongates new DNA. A sensitive film was placed over the membrane and time was allowed for the radiation to expose the film. Legal. In the elongation phase, the fully-assembled ribosome starts to slide along the mRNA. This is because A-T base pairs have two hydrogen (H-) bonds that require less energy to break than the three H-bonds holding G-C pairs together. 5.1: DNA Replication - Biology LibreTexts These organisms need both carbon and nitrogen to survive. The specific nucleotide sequence, A: DNA replicationis theprocessby whichDNA makes a copy of itself during cell division. ATP Carbohydrates Condensation Reaction DNA and RNA DNA replication Denaturation Enzymes Factors Affecting Enzyme Activity Fatty Acids Hydrolysis Reaction Inorganic Ions Lipids Measuring enzyme-controlled reactions Monomers Monomers and Polymers Monosaccharides Nucleic Acids Nucleotides Polymer Polysaccharides Protein Structure Proteins The. A student heats a liquid on a burner. The separated DNA strands serve as templates for new DNA synthesis. There are three main steps to DNA replication: initiation, elongation, and termination. DNA replication is a sequence of repeated condensation (dehydration synthesis) reactions linking nucleotide monomers into a DNA polymer. b. is a recessive trait. c. survivorship Increased DNA unwinding would cause the phosphodiester bonds in the DNA to rupture, fragmenting the DNA. This tRNA carries the amino acid Methionine (Met). A tRNA molecule with the anticodon CGA will bind to the first position (A) site of the ribosome. DNA, A: DNA replication is the synthesis of new copies of DNA and occurs before cell division. Initiation Stage. What is DNA replication? DNA is a double standard structure that is formed of 4 bases called cytosine thymine adenine guanine, hence before we start its replication we must separate the two strands individually. C These two different breathing systems allow adult frogs to shift between aquatic habitats (which require skin respiration) and land habitats (which are more suited to lung respiration). 5.4 DNA Replication - Human Biology - Thompson Rivers University Cells Can Replicate Their DNA Precisely - Nature This energy being lost cannot be used by the organisms on the next level. Patterns of death rate indicate how age at death influences population size. This is even true for circular bacterial chromosomes, if the circle is broken! This video is an update from our old D. The requirement for primases at replication forks is shown below. The amino acid its carrying (alanine) forms a peptide bond with Met. The graph below summarizes their results. This way it will be minimized damage of DNA molecules in healthy cells. 180 Okazaki Experiments & Fragments - Solving a Problem at an RF, 181 Okazaki Fragments are Made Beginning with RNA Primers. This process is called proofreading.If the polymerase detects that a wrong (incorrectly paired) nucleotide has been added, it will remove and replace the nucleotide right away, before continuing with DNA synthesis 1 ^1 1 start . Each time a cell divides, the two resulting daughter cells must contain exactly the same genetic information, or DNA . DNA Replication Steps: 3 Steps | Biochemistry - Biology Discussion The first position site is then ready to accept a new tRNA. The replication occurs in three basic steps as Initiation Elongation Termination. b) GCTGGAAGGCATTTAGCACG, Question:- Look at the two drawings of his autoradiographs on the next page. Accessibility StatementFor more information contact us atinfo@libretexts.org. tRNA is a type of RNA that has a place to bind to free amino acids and a special sequence of three nitrogenous bases (an anticodon) that binds to the ribosome. 7.4 years 9.8 years 13.2 years 15.6 years, Andrew Jackson was the first President of the United States who did not come from aristocracy. Frogs have four legs with strong hind legs and no tails. See our privacy policy for additional details. They remove segments called introns and then splice the remaining segments, called exons, together. This is called the start codon (AUG). Energy sustainability can best be achieved by using ______. Cairns therefore interpreted these images to be bacterial DNA in the process of replication. At this point, the large ribosomal subunit gets in position as well (its above the mRNA and the small subunit is below). A: Answer is option c.) Binds DNA sequences together to generate acontinuous strand. The Initiation Step: As seen above, no DNA polymerase can perform any de novo synthesis (contrary to RNA polymerases which can initiate by placing a complementary ribonucleoside-5-triphosphate opposite to the DNA to be transcribed). How DNA is copied - knowablemagazine.org 176 Semiconservative Bidrectional Replication From Two RFs. During translation, ribosomes and tRNA follow the instructions on the mRNA and assemble amino acids into proteins. 14.3 Basics of DNA Replication - Biology 2e | OpenStax At the same time as the RNA nucleotides are removed, DNA polymerase I catalyzes their replacement by the appropriate deoxynucleotides. We also acknowledge previous National Science Foundation support under grant numbers 1246120, 1525057, and 1413739. DNA and RNA Basics: Replication, Transcription, and Translation 14.3C: DNA Replication in Eukaryotes - Biology LibreTexts Farming became more difficult in Iraq in the 1970s because. When two daughter DNA copies are formed, they have the same sequence and are divided equally into the two daughter cells. List the 3 Basic Steps of Dna Replication Other replication mistakes can generate mutations somatic cells. Alternative splicing is the reason why: before the mRNA leaves the nucleus, its exons can be spliced together in different ways. Processes that increase the density of seawater include evaporation and sea ice formation. The elucidation of the structure of the double helix provided a hint as to how DNA divides and makes copies of itself. Polymerase chain reaction (PCR) (article) | Khan Academy In the US which is responsible for ensuring the safety of the country's drinking water, Processes that increase the density of seawater include evaporation and, Since frog lungs are poorly developed, what else do frogs do to breathe. Exons are the sequences that actually code for proteins, so theyre the ones the mRNA needs to keep. An In-depth Look at the 7 Major Steps of DNA Replication like the Greek letter \(\theta \), Cairns called them theta images. Video footage from animation in Visible Biology. Cairns recorded many images of E.coli of the sort shown below. 1.Initiation. A Either this other strand must grow in pieces in the opposite direction, or it must wait to begin synthesis until the double helix is fully unwound. When temperature is decreased and salinity is increased, the density increases. Except, A: Prokaryotes consist of a small amount of DNA, which occurs in the form of single, circular, A: Replication occurs in three major steps:the opening of the double helix and separation of the DNA, A: The DNA replication is the process of formation of DNA in which one strand of DNA act as the, A: Transcription is a process in which the information in the template strand of a DNA is copied into a, A: DNA replication is the process by which new DNA is synthesized from the old DNA. Growing awareness of time and orientation for the future. Today, were going to give you a primer on the basics of DNA. Since no known DNA polymerase can start synthesizing new DNA strands from scratch, this is a problem! The US Environmental Protection Energy or EPA is responsible for ensuring the country's drinking water to be safe and with good quality. Molecular structure of DNA. If you want to learn more about cells, check out these related VB Blog posts: For more information about the structure of DNA and chromosomes, check out our DNA eBook! Sometimes I get tired because it seems like all we do is work, work, work! Telomerase consists of several proteins and an RNA. He saw collectivism as intrinsically tied, as well as socialism and dictatorships. Click the card to flip The double helix must "unwind" Click the card to flip 1 / 17 Flashcards Learn Test Match Created by megaboo Terms in this set (17) What is the 1st step of DNA replication? Which of these materials in the compost bin is MOST LIKELY a good source of nitrogen? Of course, not all mistakes are caught by this or other repair mechanisms (see DNA Repair, below). The answer would be B. We have considered most of the molecular players in replication. Afterward, the CGA tRNA (carrying the Met-Ala chain) moves to the second position and the UAC tRNA enters the E binding site. Renewable energy compares to the provision of energy via renewable sources which are simply replaced fast enough as being used. Each Okazaki fragment would have to begin with a 5 RNA primer, creating yet another dilemma! Animals that are the least specialized generally stand the best chance of survival when the environment suddenly and drastically changes because they are able to -, Characteristics of the cell wall include which of the following. REPLICATION : It is the process in the central dogma where DNA strands unwinds and, A: Initiation of DNA replication involves making the target DNA accessible to the enzymes and proteins, A: Complementary base pairing occurs between the base pairs of DNA. DNA replication is the process by which cells make copies of their genetic material. During initiation, the strand of mRNA forms a loop, and a small ribosomal subunit (the bottom of the ribosome) hooks onto it and finds a sequence of bases that signals it to begin transcription. Essentially, what happens during transcription is that an mRNA copies down the instructions for making a protein from DNA. In 1904, Russia went to war with __________. For example, if allele a is for the red color of the flower and A for the white, heterozygous Aa will give pink color. It is known that gamma rays are able to damage DNA molecules in the cells by interrupting DNA strands. The density of seawater primarily depends on two factors, temperature and its salinity. 2.Elongation. If these somatic mutations escape correction, they can have serious consequences, including the generation of tumors and cancers. This process takes us from one starting molecule to two "daughter" molecules, with each newly formed double helix containing one new and one old strand. This page titled 9.2: DNA Replication is shared under a CC BY license and was authored, remixed, and/or curated by Gerald Bergtrom. Limiting contact between gamma rays and healthy tissue is important because? Another enzyme, RNA primase, synthesizes an RNA primer that is about five to ten nucleotides long and complementary to the DNA. If one strand of DNA must be replicated in fragments, then those fragments would have to be stitched (i.e., ligated) together. However, the implementation of such is governed by the EPA. The semi-conservative method suggests that each of the two parental DNA strands act . Since RNA polymerases (enzymes that catalyze RNA synthesis) are the only nucleotide polymerase that can grow a new nucleic acid strand against a DNA template from scratch (i.e., from the first base), it was suggested that RNA might be the primer, After synthesis of a short RNA primer, new deoxynucleotides would be added to its 3 end by DNA polymerase. List problems if any A: DNA replication is the process through which two identical DNA molecules are produced from a, A: Introduction Click through this tutorial on DNA replication. This tiny biological structure is the ultimate instruction manual, containing the recipes for the proteins your body needs to develop and function. PLEASE DO THE HANDWRITING. C Obviously, this does not happen. DNA replication:- DNA replication is the biological process by which a molecule of DNA, A: DNA is a molecule made up of a chain of identical five-carbon sugars (polymers) that are linked, A: DNA replication is defined as the process through which the replication of DNA is achieved. Replication depends on the pairing of bases between the two strands of DNA. First week only $4.99! That characteristic of gamma rays is used in the treatment of tumors. An idea was that gamma rays will damage DNA molecules of tumor cells and, consequently, prevent uncontrollably divisions of tumor cells. Unwinds the DNA double helix at the Replication Fork. We also acknowledge previous National Science Foundation support under grant numbers 1246120, 1525057, and 1413739. As Cairns suggested and others demonstrated, replication proceeds in two directions from the origin to form a replicon with its two replication forks (RFs). DNA unwinds from the histones. The A = T and G C base pairs form the rungs of this helical . This is carried out by an enzyme called helicase which breaks the hydrogen bonds holding the complementary bases of DNA together (A with T, C with G). X and Y sex chromosomes only have certain regions (autosomal regions) that are homologous. DNA Replication - National Human Genome Research Institute DNA Replication Steps and Process - Study.com Definition Definition Mechanism by which deoxyribonucleic acid (DNA) is capable of producing an exact copy of itself. The cells were harvested and the DNA was isolated. Carol Greider, Jack Szostak and Elizabeth Blackburn shared the 2009 Nobel Prize in Physiology or Medicine for discovering telomerase. The sides of this twisted ladder are composed of alternating molecules of sugar (deoxyribose, to be precise) and a phosphate group. The process occurs in three main steps: DNA structure and storage. B is a dominant allele, determining the blue color of a butterfly. There were three models suggested (Figure \(\PageIndex{1}\)): conservative, semi-conservative, and dispersive. b. The arrangement, or sequence, of the nucleotides along, A: DNA replication is the process of making two identical copies of DNA (deoxyribonucleic acid) from, A: DNA replication is the process by which a double stranded DNA molecule is copied to produce two, A: Meanwhile, in the process of cell division, DNA replication is known to the state to follow the. In prokaryotic, A: Since you have posted a question with multi subparts, we will solve the first three subparts for, A: DNA polymerase 1 provides three distinct catalytic activities: Testing these hypotheses revealed the topoisomerase enzymes. An idea was that gamma rays will damage DNA molecules of tumor cells and, consequently, preventuncontrollably divisions of tumor cells. My family lives in a society based on agriculture, which is great because we get to stay in one place. The 3 basic steps of DNA replication are: initiation, elongation and termination. Eukaryotic DNA is bound to basic proteins known as histones to form structures called nucleosomes. Renewable energy is energy that is obtained from renewable resources, which are naturally provided on a human timescale, such as sunlight, wind, rain, tides, waves, and geothermal heat. There are four main biomolecules., A: A cell's genetic material is DNA. Finally, when a fragment is entirely DNA, DNA ligase links it to the rest of the already assembled lagging strand DNA. Codominance is one of the examples that there are exceptions. Polymerase chain reaction, or PCR, is a technique to make many copies of a specific DNA region in vitro (in a test tube rather than an organism). C Lastly, Cacilians have no legs and are burrowing animals. Lesson on translation from the Visible Biology YouTube series with Dr. Cindy Harley. 2. Ribosomal subunits can usually be found floating around in the cytoplasm, but a ribosome will dock on the rough endoplasmic reticulum if the protein its making needs to be put into a transport vesicle. It, A: Answer: Expert Answer. Once initiated, a replication bubble (replicon) forms as repeated cycles of elongation proceed at opposite replication forks. He saw tracks of silver grains in the autoradiographs (the same kind of silver grains that create an image on film in old-fashioned photography). They are G1-phase,, A: RNA replication is not seen in cellular RNA, it is the process found only in RNA viruses. Thus, these were the major characteristics of modernization. Once initiation proteins loosen H-bonds at a replication origin, DNA helicase uses the energy of ATP hydrolysis to unwind the double helix. around 99.9% of your DNA is the same as that of every other human, even the largest cells are just over 100m, wasnt observed by scientists until mid-20th century, Anatomy & Physiology: Parts of a Human Cell, Tiny Transportation: Passive vs. DNA (deoxyribonucleic acid) is one of the most important molecules in your body, and though around 99.9% of your DNA is the same as that of every other human, the 0.1% thats different is what makes you genetically unique! Rigor mortis typically disappears after how many hours? Before replication can start, the DNA has to be made available as a template. While replication requires the participation of many nuclear proteins in both prokaryotes and eukaryotes, DNA polymerases perform the basic steps of replication, as shown in the illustration below. hbspt.cta._relativeUrls=true;hbspt.cta.load(189659, '4e82a1a5-fc2d-449c-a047-ee8746bd8b8b', {"useNewLoader":"true","region":"na1"}); Be sure to subscribe to theVisible BodyBlog for more anatomy awesomeness! G The puzzlement surrounding how replication proceeds begins with experiments that visualize replicating DNA. Or is coordination defined and achieved in some other way? In conservative replication, the parental DNA remains together, and the newly formed daughter strands are together. It appeared that eukaryotic cells could not afford to double their DNA at a bacterial rate of replication! An enzyme called DNA helicase opens up the helix structure on a segment of DNA, breaking the bonds between the nitrogenous bases. The semi-conservative method suggests that each of the two parental DNA strands act as a template for new DNA to be synthesized; after replication, each double-stranded DNA includes one parental or old strand and one new strand. The synthesis of a DNA molecule (or) DNA Replication process can be divided into THREE stages: Initiation. Watson and Crick discovered the chemical structure of DNA molecule. Correctly order the steps of DNA replication: DNA | Chegg.com Replication may be processive, meaning both new DNA strands are replicated in the same direction at the same time, smoothing out the process. However, it might very well reassemble and go around the mRNA loop again. It does this in a zipper-like fashion, leaving a replication fork behind it. DNA replication is thus initiated at multiple points along each chromosome in eukaryotes as shown in Figure 5.1.3. Therefore, the offspring in the BB x bb cross are all blue in color. During elongation, a primer sequence is added with complementary RNA nucleotides, which are then replaced by DNA nucleotides. HAGGUAC Lesson on DNA structure from the Visible Biology YouTube series with Dr. Cindy Harley. This is also the deviation of Mendels laws. What is DNA replication? - YourGenome Book: Basic Cell and Molecular Biology (Bergtrom), { "9.01:_Introduction" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "9.02:_DNA_Replication" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "9.03:_DNA_Repair" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "9.04:_Key_Words_and_Terms" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()" }, { "00:_Front_Matter" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "01:_Cell_Tour_Lifes_Properties_and_Evolution_Studying_Cells" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "02:_Basic_Chemistry_Organic_Chemistry_and_Biochemistry" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "03:_Details_of_Protein_Structure" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "04:_Bioenergetics" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "05:_Enzyme_Catalysis_and_Kinetics" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "06:_Glycolysis_the_Krebs_Cycle_and_the_Atkins_Diet" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "07:_Electron_Transport_Oxidative_Phosphorylation_and_Photosynthesis" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "08:_DNA_Chromosomes_and_Chromatin" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "09:_Details_of_DNA_Replication_and_Repair" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "10:_Transcription_and_RNA_Processing" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "11:_The_Genetic_Code_and_Translation" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "12:_Regulation_of_Transcription_and_Epigenetic_Inheritance" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "13:_Post_Transcriptional_Regulation_of_Gene_Expression" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "14:_Repetitive_DNA_A_Eukaryotic_Genomic_Phenomenon" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "15:_DNA_Technologies" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "16:_Membrane_Structure" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "17:_Membrane_Function" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "18:_The_Cytoskeleton_and_Cell_Motility" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "19:_Cell_Division_and_the_Cell_Cycle" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "20:_The_Origins_of_Life" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()", "zz:_Back_Matter" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass230_0.b__1]()" }, [ "article:topic", "showtoc:no", "license:ccby", "authorname:gbergtrom" ], https://bio.libretexts.org/@app/auth/3/login?returnto=https%3A%2F%2Fbio.libretexts.org%2FBookshelves%2FCell_and_Molecular_Biology%2FBook%253A_Basic_Cell_and_Molecular_Biology_(Bergtrom)%2F09%253A_Details_of_DNA_Replication_and_Repair%2F9.02%253A_DNA_Replication, \( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}}}\) \( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash{#1}}} \)\(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\) \(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\)\(\newcommand{\AA}{\unicode[.8,0]{x212B}}\), A. Visualizing Replication and Replication Forks. Before you read further, you must know the basic structure of DNA. He inferred that replication starts at a single origin of replication on the bacterial chromosome, proceeding around the circle to completion. Cairns autoradiographs and the measurements that led him to conclude that he was looking at images of bacterial circular chromosomes are illustrated below. The ladders steps are composed of two nitrogenous bases, held together with hydrogen bonds. Examples are coffee grounds and grass clippings. After its all cleaned up and ready to go, the mRNA leaves the nucleus and goes out to fulfill its destiny: taking part in translation, the second half of protein construction. A Each one of these is called a chromosome. Without mutations in germ line cells (egg and sperm), there would be no mutations and no evolution, and without evolution, life itself would have reached a quick dead end! Available energy would increase from the mouse to the hawk. One of the key players is the enzyme DNA polymerase, also known as DNA pol. I have never been taught how to sequence so this to me is new and confusing i dont know what i am doing. Note in the left-hand strand the phosphate group is in the "up" position, and in the right-hand strand, the . The genetic material is usually the DNA, while RNA acts as a messenger.
Recurring Donations For Nonprofits, Multinational Companies In Namibia, Capital City Crush Softball, Who Owns Westminster Crackers, Articles L

list the 3 basic steps of dna replication 2023