DNA replication is the process whereby a cell makes an identical copy of its DNA during cell division. It involves unwinding the DNA double helix into single strands, which then serve as templates for new strands to be synthesized in the opposite direction by DNA polymerases. The DNA polymerases can only add nucleotides to the 3' end of the growing strand, so replication occurs in both the 5' to 3' direction on one strand (the leading strand) and in short fragments joined together on the other (the lagging strand). Telomeres protect chromosome ends from erosion during replication. A complex team of enzymes including DNA polymerases, helicase, primase, ligase and single-stranded binding proteins work together to efficiently and
DNA replication is semi-conservative and involves many enzymes. It begins at a replication origin where the DNA unwinds. RNA primers are added and DNA polymerase adds nucleotides to the 3' end of the primers to synthesize new DNA strands. The leading strand is synthesized continuously while the lagging strand is synthesized in fragments that are later joined. Transcription and translation then convert gene information into proteins.
This document provides an overview of DNA replication and protein synthesis. It begins by outlining the learning objectives, which are to describe basic cell chemicals, explain their physical and chemical characteristics, and understand their physiological functions. The topics covered include the basic chemical substances in cells, with a focus on nucleic acids such as DNA and RNA. DNA replication is then described as the process by which DNA makes identical copies of itself. Finally, proteins are defined as large organic compounds composed of amino acid chains that are specified by genes.
#2 donohue dna, protein synthesis and biotechMaria Donohue
The document provides an overview of DNA structure and function, explaining that DNA contains genetic information that is copied through DNA replication and used to direct protein synthesis. It describes the basic units of DNA including nucleotides, bases, and the DNA double helix, and explains how genes are expressed through transcription of DNA to mRNA and translation of mRNA to proteins. The document also discusses DNA analysis techniques like DNA fingerprinting used in forensics.
This document discusses DNA structure and replication. It begins by describing DNA as a chemical that stores genetic information and can be copied from one generation to the next. DNA and RNA are made of nucleotides consisting of a nitrogenous base, sugar, and phosphate. Watson and Crick discovered that DNA has a double helix structure, where the bases on each strand pair in a complementary fashion. DNA replicates via a semi-conservative mechanism using DNA polymerases. The genetic information in DNA is expressed through transcription of DNA to mRNA and translation of mRNA to proteins.
1) The document reviews biological compounds including carbohydrates, lipids, proteins, and nucleic acids.
2) It describes the structures of proteins including primary, secondary, tertiary, and quaternary structure.
3) Nucleic acids are composed of nucleotides that are made up of phosphate groups, sugars (ribose or deoxyribose), and nitrogenous bases. DNA and RNA differ in their sugar and base components.
The document summarizes key concepts about the structure and function of DNA and genes. It describes experiments that showed DNA is the genetic material, including Griffith's transformation experiment and the Hershey-Chase experiment. It explains that DNA is made of nucleotides, has a double helix structure, and replicates semiconservatively. The flow of genetic information from DNA to RNA to protein is summarized, including transcription, RNA processing, the genetic code, translation, and protein synthesis.
This document is a multiple choice test on chapters 12 and 13 of an AP Biology textbook. It contains 23 multiple choice questions about DNA structure and replication. The questions cover topics like Griffith's experiments, Chargaff's rules, Watson and Crick's discovery of the DNA structure, semiconservative replication, Meselson and Stahl's experiments, replication forks, Okazaki fragments, and replication in bacteria and eukaryotes. It also includes a diagram labeling exercise related to DNA replication.
Caesar's wife Agrippina poisoned him by mixing poisonous Amanita caesarea mushrooms into his favorite mushroom dish, as these mushrooms contain a substance that blocks the enzyme needed for cells to transcribe mRNA from DNA, leading to liver failure and death for Caesar two days later. DNA holds the genetic instructions for cells and is replicated before cell division so each new cell has a copy, while RNA carries copies of the DNA instructions out of the nucleus to direct protein production through transcription and translation.
DNA replication is semi-conservative and involves many enzymes. It begins at a replication origin where the DNA unwinds. RNA primers are added and DNA polymerase adds nucleotides to the 3' end of the primers to synthesize new DNA strands. The leading strand is synthesized continuously while the lagging strand is synthesized in fragments that are later joined. Transcription and translation then convert gene information into proteins.
This document provides an overview of DNA replication and protein synthesis. It begins by outlining the learning objectives, which are to describe basic cell chemicals, explain their physical and chemical characteristics, and understand their physiological functions. The topics covered include the basic chemical substances in cells, with a focus on nucleic acids such as DNA and RNA. DNA replication is then described as the process by which DNA makes identical copies of itself. Finally, proteins are defined as large organic compounds composed of amino acid chains that are specified by genes.
#2 donohue dna, protein synthesis and biotechMaria Donohue
The document provides an overview of DNA structure and function, explaining that DNA contains genetic information that is copied through DNA replication and used to direct protein synthesis. It describes the basic units of DNA including nucleotides, bases, and the DNA double helix, and explains how genes are expressed through transcription of DNA to mRNA and translation of mRNA to proteins. The document also discusses DNA analysis techniques like DNA fingerprinting used in forensics.
This document discusses DNA structure and replication. It begins by describing DNA as a chemical that stores genetic information and can be copied from one generation to the next. DNA and RNA are made of nucleotides consisting of a nitrogenous base, sugar, and phosphate. Watson and Crick discovered that DNA has a double helix structure, where the bases on each strand pair in a complementary fashion. DNA replicates via a semi-conservative mechanism using DNA polymerases. The genetic information in DNA is expressed through transcription of DNA to mRNA and translation of mRNA to proteins.
1) The document reviews biological compounds including carbohydrates, lipids, proteins, and nucleic acids.
2) It describes the structures of proteins including primary, secondary, tertiary, and quaternary structure.
3) Nucleic acids are composed of nucleotides that are made up of phosphate groups, sugars (ribose or deoxyribose), and nitrogenous bases. DNA and RNA differ in their sugar and base components.
The document summarizes key concepts about the structure and function of DNA and genes. It describes experiments that showed DNA is the genetic material, including Griffith's transformation experiment and the Hershey-Chase experiment. It explains that DNA is made of nucleotides, has a double helix structure, and replicates semiconservatively. The flow of genetic information from DNA to RNA to protein is summarized, including transcription, RNA processing, the genetic code, translation, and protein synthesis.
This document is a multiple choice test on chapters 12 and 13 of an AP Biology textbook. It contains 23 multiple choice questions about DNA structure and replication. The questions cover topics like Griffith's experiments, Chargaff's rules, Watson and Crick's discovery of the DNA structure, semiconservative replication, Meselson and Stahl's experiments, replication forks, Okazaki fragments, and replication in bacteria and eukaryotes. It also includes a diagram labeling exercise related to DNA replication.
Caesar's wife Agrippina poisoned him by mixing poisonous Amanita caesarea mushrooms into his favorite mushroom dish, as these mushrooms contain a substance that blocks the enzyme needed for cells to transcribe mRNA from DNA, leading to liver failure and death for Caesar two days later. DNA holds the genetic instructions for cells and is replicated before cell division so each new cell has a copy, while RNA carries copies of the DNA instructions out of the nucleus to direct protein production through transcription and translation.
Genetics molecules like DNA and RNA have the ability to carry genetic instructions and replicate themselves perfectly. DNA contains genes which provide the code for protein production. The genetic code is expressed through transcription of DNA to mRNA and translation of mRNA to proteins. DNA replication ensures genetic information is preserved as cells divide. Mutations can occur through changes in DNA sequence or structure and generate genetic variability in populations.
This document summarizes the process of DNA replication. It discusses that DNA replication involves duplicating the genetic material in a parent cell to produce two identical copies in two daughter cells. The key steps include the unwinding of the DNA double helix at the origin of replication by helicase. RNA primers are laid down by primase and DNA polymerase adds complementary nucleotides to produce new DNA strands in the 5' to 3' direction. DNA replication results in semi-conservative replication that conserves the parental DNA strands. Replication occurs through initiation, elongation and termination stages using the enzymes DNA polymerase, helicase, primase and ligase.
Replication is the process by which DNA duplicates itself for transmission to daughter cells. It ensures exact transmission of genetic information from one cell generation to the next. Replication involves semi-conservative synthesis of new DNA strands based on existing DNA templates. It requires specific enzymes and occurs through initiation, elongation, and termination steps. Initiation begins at an origin of replication and results in unwinding and denaturation of the DNA helix. Elongation then extends the new strands bidirectionally until replication forks from adjacent origins meet and terminate the process.
Franklin collected x-ray diffraction data in the early 1950s that showed DNA has two periodicities: 3.4 Å and 34 Å. Watson and Crick then proposed a 3D model of DNA that accounted for Franklin's data, representing the first model of the DNA double helix structure. This established that DNA is made of two antiparallel strands coiled around each other.
Replication is the fundamental process by which a cell copies its DNA in order to transfer genetic information to daughter cells. It involves DNA-directed DNA synthesis where the base sequence of the newly synthesized daughter DNA is identical to the parent DNA template. Replication is semi-conservative and proceeds bidirectionally from an origin of replication. It requires various enzymes and is a highly regulated process involving initiation, elongation, and termination steps to accurately duplicate the entire genome. Precise replication is essential for preventing genetic abnormalities and maintaining inheritance of traits from parent to daughter cells.
This document discusses nucleic acids and their components. It covers topics like the different types of nucleic acid sugars (ribose, deoxyribose, dideoxy ribose), bases (purines and pyrimidines), nucleosides, nucleotides, polynucleotides, DNA vs RNA, DNA structure (double helix, hydrogen bonding between bases), Chargaff's rule, and more. It also includes review questions related to nucleic acids.
DNA and RNA molecules are linear polymers built from individual units called nucleotides connected by bonds called phosphodiester linkages. DNA and RNA are used to store and pass genetic information from one generation to the next.
The document discusses the structure and replication of DNA. It describes how DNA is made up of nucleotides containing phosphate, sugar and a nitrogenous base. The nucleotides bond together via hydrogen bonds between complementary bases to form the DNA double helix structure. DNA replication involves unwinding the double helix, synthesizing new strands complementary to each original strand, and resulting in two identical copies of the original DNA molecule. Key enzymes involved in replication include helicase, DNA polymerase, primase, ligase and others.
DNA replication is the process by which DNA copies itself for cell division. It is semi-conservative, starting at the origin and proceeding bidirectionally. The leading strand is synthesized continuously while the lagging strand is synthesized discontinuously in fragments called Okazaki fragments. RNA primers are required for initiation. DNA polymerase adds nucleotides to the 3' end of the growing strand based on complementary base pairing. Topoisomerases relieve torsional strain from unwinding. DNA ligase seals fragments on the lagging strand. Replication terminates when forks meet on the opposite side of circular DNA in prokaryotes.
The document discusses different types of RNA, ribosomes, and the cell cycle. It describes 3 main types of RNA - messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA) - and provides details about their structure, function, and relative abundance in cells. It also explains that ribosomes are composed of rRNA and protein, and facilitate protein synthesis by allowing interaction between mRNA and tRNA. Finally, it outlines the four main phases of the cell cycle - G1, S, G2, and M phase - and control mechanisms that ensure proper cell division.
This document provides an overview of nucleotides, nucleic acids, and DNA/RNA structure. It discusses the components of nucleotides, including sugars, phosphates, and nitrogenous bases. Nucleic acids are polymers of nucleotides linked by phosphodiester bonds. The two main nucleic acids are DNA and RNA. DNA contains the sugar deoxyribose and thymine, while RNA contains ribose and uracil. DNA generally takes the form of a double helix with base pairing between adenine-thymine and guanine-cytosine. RNA can have various structures and functions such as mRNA, tRNA, and rRNA.
Ch09 lecture dna and its role in heredityTia Hohler
The document summarizes key concepts about DNA and its role in heredity from a biology textbook chapter. It describes how DNA was established as the genetic material based on its presence in cell nuclei and ability to direct protein synthesis. The discovery of DNA's double-helix structure by Watson, Crick, Wilkins and Franklin is summarized, including how base-pairing allows for storage and replication of genetic information. Semiconservative replication of DNA is explained, as are DNA mutations and repair mechanisms.
The document discusses the process by which genes are transcribed into mRNA and then translated into proteins. It explains that DNA is transcribed into mRNA, which is then translated on ribosomes into amino acid chains that fold into functional proteins. The genetic code is explained, where triplets of nucleotides in mRNA (codons) encode for specific amino acids. The nearly universal nature of the genetic code is also covered.
DNA contains the genetic material of organisms in the form of nucleotides arranged in a double helix structure. The double helix is composed of two strands of nucleotides linked by hydrogen bonds between complementary nucleotide bases. DNA stores and transmits genetic information from one generation to the next through replication and cell division. It controls the development of an organism's phenotype through gene expression and can produce variations through mutation that lead to evolution over time.
The document discusses the history and structure of DNA. It describes how Miescher first isolated DNA in 1869. Griffith and Avery's experiments in the early 20th century showed that DNA was the genetic material that could be transformed between bacteria. The structure of DNA was elucidated by Chargaff, Franklin, Watson and Crick in the 1950s. They discovered that DNA is a double helix with two antiparallel strands held together by hydrogen bonds between complementary nucleotide bases, with cytosine bonding with guanine and adenine bonding with thymine. DNA stores genetic information and can self-replicate to transmit this information from parent to daughter cells.
DNA and RNA are nucleic acids that store and help express genetic information. DNA is composed of nucleotides containing deoxyribose, phosphates, and one of four nitrogenous bases (adenine, guanine, cytosine, thymine). RNA is similar but contains ribose and uracil instead of thymine. The genetic code is stored in DNA as base pair sequences in chromosomes. During cell division, DNA replicates and genes direct protein production through transcription of DNA to mRNA and translation of mRNA to proteins.
Dna rtt packet comprehensive (1 3 to start)lvilleDrFox
DNA and RNA are made up of nucleotides. DNA exists as a double helix with complementary base pairing between strands. DNA is replicated through semiconservative replication that uses each strand as a template to produce new double helix molecules.
Genetic information flows from DNA to RNA to protein. Transcription produces mRNA from DNA which is then processed. Translation reads the mRNA codon by codon to produce a polypeptide chain using tRNA and the ribosome. Mutations can occur through changes to DNA bases.
Viruses can integrate their genes into host cells and replicate through lytic and lysogenic cycles. HIV is a retrovirus that inserts its RNA into the host cell DNA.
This document provides an overview of the course MDBC 204 which covers topics related to genes, DNA replication and expression, RNA synthesis and protein synthesis. It discusses the key discoveries in genetics including the identification of DNA as the genetic material and the discovery of its double helix structure. The summary also outlines the basic mechanisms of DNA replication, transcription, translation and protein targeting in both prokaryotes and eukaryotes.
1. The document outlines the structure and function of nucleic acids DNA and RNA.
2. Key points covered include the central dogma of molecular biology, the Watson-Crick structure of DNA, types of RNA like mRNA, tRNA and rRNA, and their roles in gene expression and protein synthesis.
3. The document also discusses properties of nucleic acids like denaturation and reannealing of DNA as well as unique features of eukaryotic mRNA.
Watson and Crick discovered the double helix structure of DNA in 1953, suggesting a copying mechanism for genetic material. DNA replication involves unwinding the DNA helix, building new strands using existing strands as templates, and ensuring accurate copying. Several enzymes work together at the replication fork to copy DNA semi-conservatively. DNA polymerase adds nucleotides to growing strands using energy from nucleoside triphosphates. Okazaki fragments are produced on the lagging strand and joined by ligase. Telomeres prevent chromosome erosion after each replication. Together, this complex process copies the genome with high fidelity in a matter of hours.
1) DNA replication is the process by which DNA copies itself during cell division. It involves unwinding the DNA double helix and using each strand as a template to build new partner strands.
2) Key enzymes involved in DNA replication include helicase, which unwinds the DNA; DNA polymerase, which builds the new strands; and ligase, which seals the DNA.
3) The two strands of DNA replicate in opposite directions from a replication fork. One strand replicates continuously while the other replicates in fragments that are later joined.
Nucleic acids function to store genetic information. They are made up of nucleotides which consist of a nitrogen base, a pentose sugar, and a phosphate group. DNA and RNA are examples of nucleic acids, with DNA being double-stranded and RNA typically single-stranded. Nucleic acids store the blueprint of life in the form of genes and transfer this information from parent cells to offspring cells.
Genetics molecules like DNA and RNA have the ability to carry genetic instructions and replicate themselves perfectly. DNA contains genes which provide the code for protein production. The genetic code is expressed through transcription of DNA to mRNA and translation of mRNA to proteins. DNA replication ensures genetic information is preserved as cells divide. Mutations can occur through changes in DNA sequence or structure and generate genetic variability in populations.
This document summarizes the process of DNA replication. It discusses that DNA replication involves duplicating the genetic material in a parent cell to produce two identical copies in two daughter cells. The key steps include the unwinding of the DNA double helix at the origin of replication by helicase. RNA primers are laid down by primase and DNA polymerase adds complementary nucleotides to produce new DNA strands in the 5' to 3' direction. DNA replication results in semi-conservative replication that conserves the parental DNA strands. Replication occurs through initiation, elongation and termination stages using the enzymes DNA polymerase, helicase, primase and ligase.
Replication is the process by which DNA duplicates itself for transmission to daughter cells. It ensures exact transmission of genetic information from one cell generation to the next. Replication involves semi-conservative synthesis of new DNA strands based on existing DNA templates. It requires specific enzymes and occurs through initiation, elongation, and termination steps. Initiation begins at an origin of replication and results in unwinding and denaturation of the DNA helix. Elongation then extends the new strands bidirectionally until replication forks from adjacent origins meet and terminate the process.
Franklin collected x-ray diffraction data in the early 1950s that showed DNA has two periodicities: 3.4 Å and 34 Å. Watson and Crick then proposed a 3D model of DNA that accounted for Franklin's data, representing the first model of the DNA double helix structure. This established that DNA is made of two antiparallel strands coiled around each other.
Replication is the fundamental process by which a cell copies its DNA in order to transfer genetic information to daughter cells. It involves DNA-directed DNA synthesis where the base sequence of the newly synthesized daughter DNA is identical to the parent DNA template. Replication is semi-conservative and proceeds bidirectionally from an origin of replication. It requires various enzymes and is a highly regulated process involving initiation, elongation, and termination steps to accurately duplicate the entire genome. Precise replication is essential for preventing genetic abnormalities and maintaining inheritance of traits from parent to daughter cells.
This document discusses nucleic acids and their components. It covers topics like the different types of nucleic acid sugars (ribose, deoxyribose, dideoxy ribose), bases (purines and pyrimidines), nucleosides, nucleotides, polynucleotides, DNA vs RNA, DNA structure (double helix, hydrogen bonding between bases), Chargaff's rule, and more. It also includes review questions related to nucleic acids.
DNA and RNA molecules are linear polymers built from individual units called nucleotides connected by bonds called phosphodiester linkages. DNA and RNA are used to store and pass genetic information from one generation to the next.
The document discusses the structure and replication of DNA. It describes how DNA is made up of nucleotides containing phosphate, sugar and a nitrogenous base. The nucleotides bond together via hydrogen bonds between complementary bases to form the DNA double helix structure. DNA replication involves unwinding the double helix, synthesizing new strands complementary to each original strand, and resulting in two identical copies of the original DNA molecule. Key enzymes involved in replication include helicase, DNA polymerase, primase, ligase and others.
DNA replication is the process by which DNA copies itself for cell division. It is semi-conservative, starting at the origin and proceeding bidirectionally. The leading strand is synthesized continuously while the lagging strand is synthesized discontinuously in fragments called Okazaki fragments. RNA primers are required for initiation. DNA polymerase adds nucleotides to the 3' end of the growing strand based on complementary base pairing. Topoisomerases relieve torsional strain from unwinding. DNA ligase seals fragments on the lagging strand. Replication terminates when forks meet on the opposite side of circular DNA in prokaryotes.
The document discusses different types of RNA, ribosomes, and the cell cycle. It describes 3 main types of RNA - messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA) - and provides details about their structure, function, and relative abundance in cells. It also explains that ribosomes are composed of rRNA and protein, and facilitate protein synthesis by allowing interaction between mRNA and tRNA. Finally, it outlines the four main phases of the cell cycle - G1, S, G2, and M phase - and control mechanisms that ensure proper cell division.
This document provides an overview of nucleotides, nucleic acids, and DNA/RNA structure. It discusses the components of nucleotides, including sugars, phosphates, and nitrogenous bases. Nucleic acids are polymers of nucleotides linked by phosphodiester bonds. The two main nucleic acids are DNA and RNA. DNA contains the sugar deoxyribose and thymine, while RNA contains ribose and uracil. DNA generally takes the form of a double helix with base pairing between adenine-thymine and guanine-cytosine. RNA can have various structures and functions such as mRNA, tRNA, and rRNA.
Ch09 lecture dna and its role in heredityTia Hohler
The document summarizes key concepts about DNA and its role in heredity from a biology textbook chapter. It describes how DNA was established as the genetic material based on its presence in cell nuclei and ability to direct protein synthesis. The discovery of DNA's double-helix structure by Watson, Crick, Wilkins and Franklin is summarized, including how base-pairing allows for storage and replication of genetic information. Semiconservative replication of DNA is explained, as are DNA mutations and repair mechanisms.
The document discusses the process by which genes are transcribed into mRNA and then translated into proteins. It explains that DNA is transcribed into mRNA, which is then translated on ribosomes into amino acid chains that fold into functional proteins. The genetic code is explained, where triplets of nucleotides in mRNA (codons) encode for specific amino acids. The nearly universal nature of the genetic code is also covered.
DNA contains the genetic material of organisms in the form of nucleotides arranged in a double helix structure. The double helix is composed of two strands of nucleotides linked by hydrogen bonds between complementary nucleotide bases. DNA stores and transmits genetic information from one generation to the next through replication and cell division. It controls the development of an organism's phenotype through gene expression and can produce variations through mutation that lead to evolution over time.
The document discusses the history and structure of DNA. It describes how Miescher first isolated DNA in 1869. Griffith and Avery's experiments in the early 20th century showed that DNA was the genetic material that could be transformed between bacteria. The structure of DNA was elucidated by Chargaff, Franklin, Watson and Crick in the 1950s. They discovered that DNA is a double helix with two antiparallel strands held together by hydrogen bonds between complementary nucleotide bases, with cytosine bonding with guanine and adenine bonding with thymine. DNA stores genetic information and can self-replicate to transmit this information from parent to daughter cells.
DNA and RNA are nucleic acids that store and help express genetic information. DNA is composed of nucleotides containing deoxyribose, phosphates, and one of four nitrogenous bases (adenine, guanine, cytosine, thymine). RNA is similar but contains ribose and uracil instead of thymine. The genetic code is stored in DNA as base pair sequences in chromosomes. During cell division, DNA replicates and genes direct protein production through transcription of DNA to mRNA and translation of mRNA to proteins.
Dna rtt packet comprehensive (1 3 to start)lvilleDrFox
DNA and RNA are made up of nucleotides. DNA exists as a double helix with complementary base pairing between strands. DNA is replicated through semiconservative replication that uses each strand as a template to produce new double helix molecules.
Genetic information flows from DNA to RNA to protein. Transcription produces mRNA from DNA which is then processed. Translation reads the mRNA codon by codon to produce a polypeptide chain using tRNA and the ribosome. Mutations can occur through changes to DNA bases.
Viruses can integrate their genes into host cells and replicate through lytic and lysogenic cycles. HIV is a retrovirus that inserts its RNA into the host cell DNA.
This document provides an overview of the course MDBC 204 which covers topics related to genes, DNA replication and expression, RNA synthesis and protein synthesis. It discusses the key discoveries in genetics including the identification of DNA as the genetic material and the discovery of its double helix structure. The summary also outlines the basic mechanisms of DNA replication, transcription, translation and protein targeting in both prokaryotes and eukaryotes.
1. The document outlines the structure and function of nucleic acids DNA and RNA.
2. Key points covered include the central dogma of molecular biology, the Watson-Crick structure of DNA, types of RNA like mRNA, tRNA and rRNA, and their roles in gene expression and protein synthesis.
3. The document also discusses properties of nucleic acids like denaturation and reannealing of DNA as well as unique features of eukaryotic mRNA.
Watson and Crick discovered the double helix structure of DNA in 1953, suggesting a copying mechanism for genetic material. DNA replication involves unwinding the DNA helix, building new strands using existing strands as templates, and ensuring accurate copying. Several enzymes work together at the replication fork to copy DNA semi-conservatively. DNA polymerase adds nucleotides to growing strands using energy from nucleoside triphosphates. Okazaki fragments are produced on the lagging strand and joined by ligase. Telomeres prevent chromosome erosion after each replication. Together, this complex process copies the genome with high fidelity in a matter of hours.
1) DNA replication is the process by which DNA copies itself during cell division. It involves unwinding the DNA double helix and using each strand as a template to build new partner strands.
2) Key enzymes involved in DNA replication include helicase, which unwinds the DNA; DNA polymerase, which builds the new strands; and ligase, which seals the DNA.
3) The two strands of DNA replicate in opposite directions from a replication fork. One strand replicates continuously while the other replicates in fragments that are later joined.
Nucleic acids function to store genetic information. They are made up of nucleotides which consist of a nitrogen base, a pentose sugar, and a phosphate group. DNA and RNA are examples of nucleic acids, with DNA being double-stranded and RNA typically single-stranded. Nucleic acids store the blueprint of life in the form of genes and transfer this information from parent cells to offspring cells.
Cytogenetics 2 replication, transcription and translationTaghreed Albalawi
DNA replication, transcription, and translation are essential biological processes. DNA replication involves unwinding the DNA double helix and using each strand as a template to synthesize new strands through the actions of enzymes like DNA polymerase and ligase. Transcription copies the information in DNA to messenger RNA (mRNA) in the cell nucleus. Translation then uses the mRNA template to assemble a protein from amino acids on ribosomes based on the genetic code. These processes are precisely coordinated to allow genetic information to direct the synthesis of proteins.
- DNA replication involves unwinding the DNA double helix at the replication fork and using each single strand as a template to build new complementary strands in a semi-conservative manner, where each new double helix contains one original and one new strand.
- Replication proceeds bidirectionally from an origin of replication as the replication fork moves along the DNA in both directions. The leading strand is synthesized continuously while the lagging strand is synthesized discontinuously in fragments called Okazaki fragments.
- Several DNA polymerases and other proteins work together accurately and efficiently to copy the billions of bases in human DNA within a few hours during cell division.
The document discusses the history and structure of nucleic acids. It describes how Friedrich Miescher first isolated nuclein in 1869 and how the tetranucleotide hypothesis proposed nucleic acids contained one of each nucleotide connected by phosphodiester linkages. Later, Avery, MacLeod and McCarty showed DNA could transform cells, supporting it as the molecule of heredity. Watson and Crick finally determined DNA's double helix structure in 1953. There are two main types of nucleic acids, DNA and RNA, which have similar structures but RNA contains uracil instead of thymine and has a 2' hydroxyl group.
DNA replication occurs semi-conservatively, with each parental strand serving as a template for synthesis of a new complementary strand. This results in two identical DNA molecules, each with one original parental strand and one newly synthesized strand. Replication is initiated at the origin of replication and proceeds bidirectionally around the circular bacterial chromosome. Enzymes such as helicase unwind the parental DNA, topoisomerases relieve supercoiling, and DNA polymerase adds complementary nucleotides using the parental strands as templates.
This document summarizes the process of DNA replication. It begins with parent DNA unwinding and separating into two strands. Each strand then serves as a template for new strand synthesis in a semi-conservative manner. In prokaryotes, replication occurs bidirectionally from a single origin of replication. Eukaryotes have multiple origins of replication to allow for simultaneous replication bubbles. The document discusses enzymes involved like DNA polymerases and primase, as well as mechanisms like Okazaki fragment formation and resolution. It concludes by describing the unique process of telomere replication through the reverse transcriptase telomerase to overcome the end-replication problem.
DNA replication is the process where a cell makes an identical copy of its DNA before cell division. It involves unwinding the DNA double helix into single strands, and using DNA polymerase to add complementary nucleotides to each strand to make two new double helix DNA molecules. It is semiconservative, starting at the origin of replication and proceeding bidirectionally. The leading strand is synthesized continuously while the lagging strand makes short Okazaki fragments that are later joined. DNA replication occurs with high fidelity to maintain genetic integrity as cells divide.
The document discusses DNA replication in prokaryotes and eukaryotes. It explains that replication involves initiation at an origin of replication, followed by unwinding of the DNA double helix by helicase. RNA primers are synthesized by primase and DNA polymerase adds nucleotides to the primers to elongate DNA strands. In prokaryotes, leading and lagging strands are synthesized continuously and discontinuously respectively to form Okazaki fragments. Enzymes like DNA polymerase, ligase, and topoisomerase ensure high fidelity and processivity of replication. Telomerase maintains telomere integrity in eukaryotes during DNA replication.
#2 donohue dna, protein synthesis and biotechMaria Donohue
The document provides an overview of DNA structure and function, explaining that DNA contains the genetic code for all living things and is made up of nucleotides containing nitrogenous bases that pair up in the DNA double helix. It describes how DNA is replicated through the process of transcription to make mRNA and then translated to synthesize proteins. The document also discusses mutations that can occur in DNA through errors in replication or recombination and their potential effects.
DNA replication and repair involve complex multi-step processes. DNA is copied through semiconservative replication during S phase. This requires unwinding of the DNA double helix by helicase, synthesis of new strands by DNA polymerase using the parental strands as templates, and ligation by ligase. DNA polymerase can only add nucleotides to the 3' end, so the leading strand is continuously synthesized while the lagging strand involves discontinuous Okazaki fragments. Telomerase protects chromosome ends from shortening during replication. DNA repair pathways such as base excision repair and nucleotide excision repair help correct errors and damage to maintain genome integrity.
The document discusses DNA replication and transcription. It describes:
1) DNA replication occurs during the S phase of the cell cycle in the nucleus, involving unwinding of the DNA double helix, synthesis of new strands, and production of two identical copies of DNA.
2) Transcription is the process by which a segment of DNA is used as a template to produce a complementary RNA message. There are three types of RNA involved in protein synthesis - mRNA, rRNA and tRNA.
This document discusses several key aspects of DNA structure and function:
1) Chromosomes contain DNA, histone proteins, and some RNA. DNA contains a code made up of four nucleotide bases that determines the sequence of amino acids in proteins.
2) DNA replicates semi-conservatively, with each parent strand serving as a template to produce two new DNA double helices.
3) Replication requires DNA polymerase, nucleotides, and energy and proceeds through initiation, elongation, and termination steps at the replication fork.
A reaction in which daughter DNAs are synthesized using the parental DNAs as the template.
Transferring the genetic information to the descendant generation with a high fidelity
Semi-conservative replication
Bidirectional replication
Semi-continuous replication
High fidelity
Replication starts from unwinding the dsDNA at a particular point (called origin), followed by the synthesis on each strand.
The parental dsDNA and two newly formed dsDNA form a Y-shape structure called replication fork.
The document discusses DNA replication in eukaryotes and prokaryotes. It provides details on:
1) The enzymes involved in DNA replication such as DNA polymerase, helicase, ligase, and primase.
2) The stages of DNA replication - initiation, elongation, and termination.
3) Differences in DNA replication between prokaryotes and eukaryotes such as the presence of multiple origins of replication in eukaryotes.
4) Features of DNA replication like the semi-conservative mode, discontinuous replication in the lagging strand forming Okazaki fragments, and proofreading to ensure high-fidelity replication.
This document provides a review for a Physical Science final exam, outlining 9 competencies covered on the exam. It includes 75 multiple choice and short answer questions testing understanding of concepts in motion, waves, electricity, thermodynamics, atomic structure, nuclear processes, bonding, and acids/bases. Sample questions assess knowledge of the scientific method, graphing, Newton's laws, energy transformations, electromagnetic radiation, the periodic table, nuclear reactions, and chemical equations.
This document provides 42 multi-part physics problems involving Newton's laws of motion. The problems cover concepts such as force, mass, acceleration, weight, and their relationships. Some sample answers are provided. The problems involve calculating unknown values like force, mass, or acceleration given information about real-world scenarios involving objects in motion or at rest under the influence of various forces.
1. This document discusses different types of waves including transverse, longitudinal, and electromagnetic waves. It defines key wave properties such as amplitude, wavelength, frequency, period, and wave speed.
2. Frequency is defined as the number of vibrations per second, measured in Hertz (Hz). Period is the time for one full vibration. Frequency and period are inversely related.
3. Examples are provided to demonstrate calculating wave properties like frequency, period, wavelength, and wave speed from information given about the wave.
This document discusses electrical power and energy. It explains that power is calculated as current multiplied by voltage, and is measured in watts. It asks the reader to calculate the power needed to operate a clock radio drawing 0.05 amps from a household circuit. The document also explains that electrical energy is provided by power companies and sold to homeowners in units of kilowatt-hours, which is 1000 watts delivered for one hour. It provides an example of calculating the electrical energy used and cost for a 1200W toaster oven used for 15 minutes.
This document explains the differences between alternating current (AC) and direct current (DC). It defines AC as an electric current that periodically reverses direction and changes its magnitude continuously with time in contrast to DC, which flows in one direction. The document also outlines the key characteristics of series and parallel electric circuits. Series circuits have the same current flowing through all elements and the total voltage is divided among the elements. Parallel circuits have the same voltage across each element and the total current is the sum of the currents in the individual branches. The document concludes by noting that fuses are used to prevent circuit overloading by melting and breaking the circuit if too much current passes through.
This document provides an Ohm's Law worksheet with 6 practice problems calculating voltage, current, and resistance using the equations: I = V/R, R = V/I, and V = IR. Students are asked to use these equations to find the missing value in each circuit scenario, such as calculating the voltage applied to a light bulb with a known current and resistance.
This document contains a worksheet on Ohm's Law with 14 problems. The worksheet provides the three forms of Ohm's Law and asks students to calculate values like voltage, current, and resistance using circuits with resistors and batteries. Students are asked to determine unknown values, total resistances, and currents in various circuit diagrams applying the relationships defined by Ohm's Law.
This document provides an Ohm's Law worksheet with 6 practice problems calculating voltage, current, and resistance using the equations: I = V/R, R = V/I, and V = IR. Students are asked to use these equations to find the missing value in each circuit scenario, such as calculating the voltage applied to a light bulb with a known current and resistance.
This document discusses resistance and Ohm's Law. It describes the key parts of Ohm's Law including volts, amps, and resistance. It also explains how to calculate an unknown value using two known values and Ohm's Law. Examples are provided to demonstrate calculating current and resistance using Ohm's Law. The document also discusses how resistance affects current and electric shock, and provides examples of calculating current through the body at different resistances and voltages.
Static electricity and electrical currantssbarkanic
This document defines static electricity and current electricity. It explains that static electricity is caused by an imbalance of electric charges, usually through rubbing materials together, while current electricity involves the controlled flow of electrons. It distinguishes conductors that allow electron flow from insulators that do not, and describes how static charges build up and arc in lightning.
This document covers acids and bases, including definitions, properties, examples and the pH scale. It also discusses acid rain, its effects and causes. For radioactivity, it defines different types and compares the strong force to the electric force in alpha and beta equations. It explains transmutation, half-life, fission and chain reactions. Additionally, it outlines nuclear power plants, how they create electricity from fission, reasons for past meltdowns and pros and cons of nuclear power. Finally, it addresses the big bang theory, evidence supporting it, the potential end of the universe, star formation, star types and life cycles.
This document discusses chemical equations and reactions. It explains that chemical equations are used to represent chemical reactions, and that they consist of reactants on the left side of the arrow yielding products on the right. It also describes how to balance chemical equations by adjusting coefficients so that the same number of each type of atom is on both sides of the equation. Balancing chemical equations ensures conservation of mass during chemical reactions.
Naming and writing compounds and moleculessbarkanic
This document provides instructions for writing formulas and naming ionic compounds, covalent molecules, and polyatomic ions. It explains that for ionic compounds, you write the symbols of the ions and use the crossover method to determine subscripts before naming the compound by writing the cation name followed by the anion name with "ide." For covalent molecules, Greek prefixes indicate subscripts and the name is written by specifying each element followed by the number of atoms. Polyatomic ions are also named and included in ionic compounds by looking up their formula and charge. Examples and practice problems are provided to demonstrate the process.
1) The document provides instructions for drawing Lewis structures to show ionic and covalent bonding between various elements. Students are asked to draw Lewis structures for pairs of elements, and indicate electron transfers or sharing to write chemical formulas. 2) For ionic bonds, students should draw Lewis structures, arrows to show electron transfer, charges for each ion, and chemical formulas. 3) For covalent bonds, the instructions are to draw Lewis structures, circles around shared electrons, bond structures, and chemical formulas.
The document discusses atomic spectra and the Bohr model. It explains that atoms can absorb and emit light at specific frequencies, and this atomic spectrum acts as a fingerprint that can be used to identify elements. The Bohr model describes electrons occupying different energy shells around the nucleus, and electrons absorbing and emitting energy by jumping between shells and releasing light. The document also briefly mentions flame tests and spectroscopes as methods to observe atomic spectra.
Ernest Rutherford (1871-1937) was a notable British physicist and chemist who made seminal contributions to the development of the modern atomic model. Through his gold foil experiment in 1911, Rutherford was able to formulate the Rutherford model of the atom, which established that atoms have a small, positively charged nucleus surrounded by low-mass electrons. For this breakthrough discovery, Rutherford received numerous honors including the Nobel Prize in Chemistry in 1908. His work fundamentally changed scientific understanding of atomic structure.
Lise Meitner was an Austrian/German physicist born in 1878 who made significant contributions to nuclear physics. She received her doctorate in 1905 as the second woman to earn a PhD from the University of Vienna. In 1938, Meitner, Otto Hahn, and Fritz Strassmann discovered nuclear fission when bombarding uranium with neutrons. This splitting of uranium atoms led to additional neutrons and the potential for an explosive chain reaction. Sadly, her discovery was later used in 1945 for the atomic bomb dropped on Hiroshima. Meitner received several honors for her work, including the Max Planck medal in 1949.
Murray Gell-Mann was born in 1929 and is still living. He graduated valedictorian from Columbia Grammar School and attended Yale University at age 15. Gell-Mann won the 1969 Nobel Prize in Physics. In 1964, he discovered the quark, which makes up protons and neutrons in the nucleus. Quarks have never been isolated due to their small size of 10-15 mm. Gell-Mann is also interested in activities like bird watching and collecting antiques.
Democritus was a Greek philosopher born around 460-457 BC in Abdera, Thrace. He developed the first atomic theory, proposing that all matter is made up of indivisible atoms moving through empty space. Democritus believed that atoms were the fundamental building blocks of the natural world and that their behavior determined natural phenomena. He and his mentor Leucippus are considered the founders of atomic theory. Democritus was highly respected in his lifetime for making discoveries and predictions that were later proven true.
3. Double helix structure of DNA
“It has not escaped our notice that the specific pairing we have postulated
immediately suggests a possible copying mechanism for the genetic
AP Biology
material.” Watson & Crick
4. Directionality of DNA
You need to PO nucleotide
4
number the
carbons!
it matters! N base
5′ CH2
This will be O
IMPORTANT!!
4′ ribose 1′
3′ 2′
AP Biology
OH
5. 5′
The DNA backbone PO4
Putting the DNA
backbone together base
5′ CH2
refer to the 3′ and 5′ O
4′ 1′
ends of the DNA C
3′ 2′
the last trailing carbon O
–
O P O
Sounds trivial, but…
O base
this will be 5′ CH2
IMPORTANT!! O
4′ 1′
3′ 2′
OH
AP Biology 3′
6. Anti-parallel strands
Nucleotides in DNA
backbone are bonded from
phosphate to sugar
between 3′ & 5′ carbons 5′ 3′
DNA molecule has
“direction”
complementary strand runs
in opposite direction
AP Biology 3′ 5′
7. Bonding in DNA
hydrogen
bonds
5′ 3′
covalent
phosphodiester
bonds
3′
5′
….strong or weak bonds?
AP Biology the bonds fit the mechanism for copying DNA?
How do
8. Base pairing in DNA
Purines
adenine (A)
guanine (G)
Pyrimidines
thymine (T)
cytosine (C)
Pairing
A:T
2 bonds
C:G
3 bonds
AP Biology
9. Copying DNA
Replication of DNA
base pairing allows
each strand to serve
as a template for a
new strand
new strand is 1/2
parent template &
1/2 new DNA
semi-conservative
copy process
AP Biology
10. Let’s meet
the team…
DNA Replication
Large team of enzymes coordinates replication
AP Biology
11. I’d love to be
helicase & unzip
Replication: 1st step your genes…
Unwind DNA
helicase enzyme
unwinds part of DNA helix
stabilized by single-stranded binding proteins
helicase
single-stranded binding proteins
AP Biology replication fork
12. Replication: 2nd step
Build daughter DNA
strand
add new
complementary bases
DNA polymerase III
But…
Where’s the
We’re missing
ENERGY
DNA something!
for the bonding!
Polymerase III What?
AP Biology
13. Energy of Replication
Where does energy for bonding usually come from?
We come
with our own
energy!
You energy
remember energy
ATP!
Are there
other ways
other energy
to get energy
nucleotides?
out of it?
You bet!
And we
leave behind a
CTP
GTP
TTP
ATP nucleotide! CMP
TMP
GMP
AMP
ADP
AP Biology modified nucleotide
14. Energy of Replication
The nucleotides arrive as nucleosides
DNA bases with P–P–P
P-P-P = energy for bonding
DNA bases arrive with their own energy source
for bonding
bonded by enzyme: DNA polymerase III
ATP GTP TTP CTP
AP Biology
15. 5′ 3′
Replication energy
DNA
Adding bases Polymerase III
can only add energy
nucleotides to DNA
3′ end of a growing Polymerase III
DNA strand energy
need a “starter”
DNA
Polymerase III
nucleotide to
bond to
DNA
energy
strand only grows Polymerase III
5′→3′
B.Y.O. ENERGY!
The energy rules 3′ 5′
the process
AP Biology
16. 5′ 3′ 5′ need “primer” bases to add on to 3′
energy
no energy
to bond
energy
energy
energy
energy
ligase
energy
energy
AP Biology
3′ 5′ 3′ 5′
17. Okazaki
Leading & Lagging strands
Limits of DNA polymerase III
can only build onto 3′ end of
an existing DNA strand 5′
ents
3′
Okaza
5′
ki fragm
3′
5′
3′ 5′ 5′
3′
Lagging strand
ligase
growing 3′
replication fork
5′
Leading strand
Lagging strand
3′ 5′
3′
DNA polymerase III
Okazaki fragments
joined by ligase Leading strand
AP Biology
“spot welder” enzyme continuous synthesis
18. Replication fork / Replication bubble
3′ 5′
5′ 3′
DNA polymerase III
leading strand
5′
3′ 3′ 5′
5′ 5′
5′ 3′ 3′
lagging strand
3′ 5′
5′
3′ lagging strand leading strand
5′ growing
3′ replication fork 5′
5′ growing
replication fork 5′
leading strand 3′
lagging strand
3′
5′
5′ 5′
AP Biology
19. Starting DNA synthesis: RNA primers
Limits of DNA polymerase III
can only build onto 3′ end of
an existing DNA strand 5′
3′ 5′ 3′
5′
3′
3′ 5′
growing 3′ primase
replication fork DNA polymerase III
5′
RNA 5′
RNA primer 3′
built by primase
serves as starter sequence
AP for DNA polymerase III
Biology
20. Replacing RNA primers with DNA
DNA polymerase I
removes sections of RNA DNA polymerase I
primer and replaces with 5′
DNA nucleotides 3′
3′
5′ ligase
growing 3′
replication fork
5′
RNA 5′
3′
But DNA polymerase I still
can only build onto 3′ end of
an Biology
AP existing DNA strand
21. Houston, we
have a problem!
Chromosome erosion
All DNA polymerases can
only add to 3′ end of an DNA polymerase I
existing DNA strand 5′
3′
3′
5′
growing 3′
replication fork DNA polymerase III
5′
RNA 5′
Loss of bases at 5′ ends 3′
in every replication
chromosomes get shorter with each replication
AP limit to number of cell divisions?
Biology
22. Telomeres
Repeating, non-coding sequences at the end
of chromosomes = protective cap
5′
limit to ~50 cell divisions
3′
3′
5′
growing 3′ telomerase
replication fork
5′
5′
Telomerase
TTAAGGG TTAAGGG TTAAGGG
enzyme extends telomeres 3′
can add DNA bases at 5′ end
different level of activity in different cells
AP Biology
high in stem cells & cancers -- Why?
23. Replication fork
DNA
polymerase III lagging strand
DNA
polymerase I
3’
Okazaki primase
fragments 5’
5’ ligase
SSB
3’ 5’
3’ helicase
DNA
polymerase III
5’ leading strand
3’
direction of replication
AP Biology
SSB = single-stranded binding proteins
24. DNA polymerases
DNA polymerase III
1000 bases/second! Thomas Kornberg
??
main DNA builder
DNA polymerase I
20 bases/second
editing, repair & primer removal
DNA polymerase III Arthur Kornberg
enzyme 1959
AP Biology
25. Editing & proofreading DNA
1000 bases/second =
lots of typos!
DNA polymerase I
proofreads & corrects
typos
repairs mismatched bases
removes abnormal bases
repairs damage
throughout life
reduces error rate from
1 in 10,000 to
1 in 100 million bases
AP Biology
26. Fast & accurate!
It takes E. coli <1 hour to copy
5 million base pairs in its single
chromosome
divide to form 2 identical daughter cells
Human cell copies its 6 billion bases &
divide into daughter cells in only few hours
remarkably accurate
only ~1 error per 100 million bases
~30 errors per cell cycle
AP Biology
27. What does it really look like?
1
2
3
4
AP Biology
Enzymes more than a dozen enzymes & other proteins participate in DNA replication
The energy rules the process.
In 1953, Kornberg was appointed head of the Department of Microbiology in the Washington University School of Medicine in St. Louis. It was here that he isolated DNA polymerase I and showed that life (DNA) can be made in a test tube. In 1959, Kornberg shared the Nobel Prize for Physiology or Medicine with Severo Ochoa — Kornberg for the enzymatic synthesis of DNA, Ochoa for the enzymatic synthesis of RNA.