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DNA Replication

Related:  Cellular BiologyIntro to Genetics DNA Structure and Function

I need a step by step description of DNA replication 1) The enzyme DNA Helicase "unzips" the DNA double helix, breaking the hydrogen bonds that hold the nitrogen bases together. 2) Enzymes are added to the two separated strand portions so that the strands don't twist around and come back together. The two areas on either end of the DNA where the double helix separates are called replication forks. 3) DNA Polymerase glides along the exposed strands, adding complementary nucleotides to the existing ones. 4) When DNA Polymerase is done, two identical strands of DNA have been formed- each containing one old strand and one new strand. Side note: In DNA replication, mutations can sometimes occur when the wrong nucleotide is added.

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DNA- The ins and outs! Watson and Crick's Paper Watson and Crick published a paper that described the complementary structure of DNA. This paper rocked the science world and illuminated the structure of DNA! Check out their Paper below! Watson and Crick published a paper that described the complementary structure of DNA. Watson and Crick's Paper The Complementary Structure of DNA-The paper The Complementary Structure of DNA-The paper [ DNA Replication-Explanation and Video DNA Replication-Explanation and Video Chapter 16 Outline Below is an outline of Chapter 16. Chapter 16 Outline Below is an outline of Chapter 16. Chapter 16 Outline The Cell Craft Challenge Install and Play CellCraft until you complete the 5th level. Download Cell Craft from here As you play the game, keep track of your success by filling out the cell craft worksheet (attached below). Install and Play CellCraft until you complete the 5th level. Worksheets

PopG Genetic Simulation Program version 4.01 October, 2013 This is a one-locus, two-allele genetic simulation program for use by students. At its web site is a downloadable "zip archive" which contains a Java archive file which has the Java executable as well as the Java source code. The Java source for popg is called and is in the folder src. Getting PopG You can fetch PopG using the links below. We have posted a Zip archive of PopG, including Java archives and documentation files. Fetch it here. Installing PopG Here are instructions for saving, unpacking, and installing PopG from different browsers, and on operating systems. Using Chrome on Windows, Mac OS X, or Linux Click on the link. Using Firefox on Windows, Linux, or Mac OS X Click on the link. Using Internet Explorer on Windows Click on the link. Using Safari on Mac OS X Click on the link. The Java archive The documentation page Older versions of PopG Making sure you have Java on your computer The Run menu

Synthesis of DNA There is a major difference between DNA polymerase and RNA polymerase: the RNA polymerase can synthesize a new strand whereas the DNA polymerase can only extend an existing strand. Therefore, to synthesize a DNA molecule, a short RNA molecule (~ 5 - 12 nucleotides) must be synthesize first by a special enzyme. The initiating RNA molecule is known as a primer, and the enzyme is called primase. In addition to DNA polymerase and primase, DNA replication requires helicase and single strand binding protein (SSB protein). The replication mechanisms in both bacteria and eukaryotes are similar. Figure 7-B-2. DNA polymerases can extend nucleic acid strands only in the 5' to 3' direction. Figure 7-B-3. The whole lagging strand is synthesized by repeating steps (b) to (e).

Dennis Kunkel Microscopy - Electron Microscopy Science Stock Photography Friends Have More DNA in Common Than Strangers People may unsuspectingly choose friends who have some DNA sequences in common with them, a new analysis finds. Researchers compared gene variations between nearly 2,000 people who were not biologically related, and found that friends had more gene variations in common than strangers. The study lends a possible scientific backing for the well-worn clichés, "We're just like family," or "Friends are the family you choose," the researchers said. NEWS: How The Sun Changes Your DNA "Humans are unique in that we create long-term connections with people of our species," said Nicholas Christakis, a social scientist at Yale University involved in the study. The researchers did the study because they wanted "to provide a deep evolutionary account of the origins and significance of friendship," Christakis said. The most common gene shared by friends was the "olfactory" gene, which is involved in a person's sense of smell. VIDEO: 98 Percent Of Your DNA Is Junk VIDEO: Imaginary Friends Make You Awesome

Genetic Education Resources for Teachers Genetic Education Resources for Teachers As genetics and genomics research advances rapidly through the knowledge gained from the completed human DNA sequence, teachers and educators require new classroom tools to present the rich history, complexity and excitement of the world of genetics and genomics.These teaching resources include specific teaching plans to present the history, facts and genetic terminology behind the Human Genome Project. Teaching Resources Internet-Based Tools for Teaching the Microbiome Websites, articles, research studies and more to help teach about the microbiome. Learning Tools The GeneEd Website The National Library of Medicine's genetics, education and discovery website. To view the PDFs on this page you will need Adobe Reader. To view the MS Word file on this page, you will need MS Word. To view the MS PowerPoint presentation on this page, you will need MS PowerPoint. Top of page

What is the function of an okazaki fragment An Okazaki fragment is a relatively short fragment of DNA (with no RNA primer at the 5' terminus) created on the lagging strand during DNA replication. The lengths of Okazaki fragments are between 1,000 to 2,000 nucleotides long in E. coli and are generally between 100 to 200 nucleotides long in eukaryotes. It was originally discovered in 1968 by Reiji Okazaki, Tsuneko Okazaki, and their colleagues while studying replication of bacteriophage DNA in Escherichia coli. In dealing with the synthesis of complementary DNA strands the nascent leading strand always reads 3' to 5'. Each Okazaki fragment is initiated near the replication fork at an RNA primer created by primase, and extended by DNA polymerase III. Okazaki used a pulse chase type experiment to confirm discontinuous strand replication. by my own mind...........

Visualizing How A Population Grows To 7 Billion 7 Billion: How Did We Get So Big So Fast? Watch as global population explodes from 300 million to 7 billion. Sometime Monday, the world will have more humans than ever: 7 billion, according to the U.N. The U.N. estimates that the world's population will pass the 7 billion mark on Monday. Much of that growth has happened in Asia — in India and China. Due in part to that region's extreme poverty, infant mortality rates are high and access to family planning is low. As NPR's Adam Cole reports, it was just over two centuries ago that the global population was 1 billion — in 1804. As higher standards of living and better health care are reaching more parts of the world, the rates of fertility — and population growth — have started to slow down, though the population will continue to grow for the foreseeable future. U.N. forecasts suggest the world population could hit a peak of 10.1 billion by 2100 before beginning to decline.