DNA Structure

Part of Biomodel website by Angel Herráez, Univ. de Alcalá (Spain)
Disponible también en espa&>41;ol. Também disponível em português. Disponible aussi en fran&>31;ais.
This version 4.0 works in any Java-compatible browser. Java Virtual Machine must be installed (JVM, included with some operating systems or available in Sun's Java website). More tutorials on DNA and proteins, in English, Spanish, etc., are indexed at molvisindex.org.
If you prefer using Chime for molecular models, the page using it is still available, with equivalent content and functionality.
This tutorial is designed to complement Biology or Biochemistry and Molecular Biology books, so it is not by itself a complete introduction to DNA structure. Please, check the original source for more recent versions. You can also read the version history at the bottom of this page.
Before proceeding, check that your browser has Java installed and can use the Jmol software:
Jmol test
This tutorial is designed to complement an introduction to DNA, by providing tools for a self-directed exploration. It does not tell a story (but does offer questions for students and a lesson plan for teachers). As a preamble to the tutorial below, or for a story that introduces DNA structure with interactive molecular graphics, we recommend
Exploring DNA Structure by Andrew Carter (which requires Chime).
Other DNA links.The Animated Interactive Tutorial Pages (A, B, C, D) &<60;&<60; Please use a large window for these (full-screen if your screen resolution is 800 x 600 or less):
A. Double helix by element: base pairs, hydrogen bonding
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B. The Code
0 && image.height>0){if(image.width>=700){this.width=700;this.height=image.height*700/image.width;}}"> Explanation of codons and anticodons
C. Strands and helical backbone
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D. Ends, Antiparallelism
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Questions for Students and a Lesson Plan for Teachers.More Molecules for High School Teachers.
0 && image.height>0){if(image.width>=700){this.width=700;this.height=image.height*700/image.width;}}"> More DNA Resources includes tutorials for high school students, college freshmen, interactive Shockwave simulations of agarose gel electrophoresis to learn about electrical charge of DNA, cutting with restriction endonucleases, etc.
You can request a copy of this tutorial for off-line use; once you have your own copy on your computer's hard disk, you can use it without an Internet connection (and it will run faster).
Methods, Acknowledgements, and References.
Do you know there are more tutorials at MolviZ.Org? Feedback/Requests to Eric Martz or Angel Herráez .
More about Jmol: Jmol home page.
customs declaration form,　the　Customs should report immediately to local administrative departments of foreign exchange　 and　the　bank,　then　it's　the　responsibility　 of　 local administrative departments of foreign exchange and the bank to report to local　departments　of　public security to place the case　on　file　for investigation and prosecution.4.　The administrative departments of foreign exchange　should　increase their efforts to fight against the cases of defrauding foreign　exchange by false customs declaration form. Those entities which have made use of false　customs declaration form to defraud foreign exchange,　should　be punished　in　compliance with relevant regulations on　foreign　exchange control　and　strengthen the supervision over their　buying　of　foreign exchange　in future. The administrative departments of foreign　exchange should enter those entities which have been identified having committing defrauding　 foreign　 exchange　in　the　list　of　 enterprises　 which authenticity　should　be　examined by State　Administration　of　Foreign Exchange (SAFE), and report regularly to bank and customs with a view to strengthen　the concerted supervision over the enterprises in　question. In　 the　case that this kind of entities want to buy foreign　exchange,　they　should　be　examined and checked for authenticity　in　advance　by administrative　departments of foreign exchange before they are　allowed to buy foreign exchange from banks.5.　The　administrative　departments of　commerce　and　industry　should strengthen　their　control in the course of company's　registration　and exert strict examination and check to ensure sound entry to market.6.　To the criminal clues of making false customs declaration　form　and false　 documents　 discovered　and　transferred　in　 the　 course　 of investigating　the　cases　of　cheating　foreign　exchange　by　relevant departments, departments of public security should timely place them　on file for investigation and prosecution.7.　Departments of public security, customs, foreign exchange,　commerce and　industry　should join their efforts in the course of　handling　the cases and cooperate with each other to make a through investigation into the　behavior　of　foreign exchange defrauding and　crack　down　heavily according to the law.