Orbit GC Nucleotide Assembly
This image shows guanine & cytosine paired together with cytosine facing "upwards" & guanine facing "downwards". The double bonds that are visible only on thecytosine side but are also present on the guanine side but cannot be readily seen.
This is an important feature of the Indigo Instruments 12 base pair DNA model when used as part of a lab instruction exercise. The 3 hydrogen bonds consist of a 5mm long "wobbly" bond with a white insert. Although linear hydrogen atoms are available we believe this representation along with the double bonds shown in the base pairs better illustrates the importance of the overall resonance structure.
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Current Reviews: 3
This image shows a completed base pairs with guanosine to the left and cytidine to the right. Note that the "X-pegs" that illustrate the double bonds are on top on one side and on the bottom on the other. This ensures that the strands are built anti-parallel to form the major & minor grooves.
Click here for related information or images24 Base Double Height Version, AT, CG, GC, TA,
|68218C||Atom, Orbit, O, red, 1 prong||55|
|68230C||Atom, Orbit, O, 110 degree, red||92|
|68235C||Atom, Orbit, C, planar:108-120-132, black||25|
|68236C||Atom, Orbit, C, planar: 108-126-126, black||13|
|68237C||Atom, Orbit, N, planar: 108-126-126, blue||25|
|68241C||Atom, Orbit, C, planar: 120-120-120, black||73|
|68242C||Atom, Orbit, N, planar: 120-120-120, blue||66|
|68244C||Atom, Orbit, C, tetrahedral, black||128|
|68247C||Atom, Orbit, P, tetrahedral, purple||24|
|68267C||Atom, Orbit, double/triple bond peg/insert||211|
|68186-20||Wobbly bond, 20mm, each||456|
|68186-25||Wobbly bond, 25mm, each||98|
|68186-50||Wobbly bond, 50mm, each||30|
|68366||Orbit bonds, opaque, 20mm, 15/bundle||7|
|67288C||Bond, Minit, white, 210mm||5|
4.5 Stars 2017-10-21
Once assembled, the model gives good detail about how all the different atoms fit together to make the classic double helix structure of DNA. The instructions are done reasonably well with two exceptions. The first is that when it's time to build the deoxyribose-phosphate "backbone" of the helix, the instructions show which atoms connect where, but it leaves out how they are to be rotated. The user is left to work this out by trial and error. The second is a minor error in the assembly of the stand where you're first told to put it together one way, and then later to do it a different way (positions of the nuts on the threaded rod). Having said that, I'd still buy it again.
Thanks very much for the feedback. We are planning to revise these instructions & your recommendations will be incorporated.
5 Stars 2016-12-23
After I decided to get a model of DNA, I spent quite a bit of time researching it. I found this one pretty quickly, but kept looking. Finally, I decided to buy it. I am really glad I did. I have studied DNA for some time now, and putting this model together really brought things together in my head. Two dimensional drawings in books became a three dimensional representation right before my eyes. The major/minor grooves and how they are formed became much clearer. This is a cool model. The price is right, too. The less expensive models are fine but don't provide the detail this one does. In my view it was worth spending extra for more detail. Indigo says this is their best teaching model, and I agree. Indigo's service is stellar, too. My order was shipped immediately and arrived in good shape. The directions were fine if in need of some updating. Chris Bingleman helped me a lot-he is a credit to your company. He returned every email I sent, and quickly I might add. I talked with others at the company and was impressed. They care. If you want a really nice DNA model to put on display, this is a good one. I'd do it again.
Thanks for your insights.
4 Stars 2016-12-02
This model is fantastic but is not for the faint of heart. I had students assemble it in class as part of our unit on nucleic acid structure. It took two classes, an occasional bored research group member, and an awful lot of quality control on my part to actually finish it! The most difficult part is figuring out what tubes to use for what bonds. It is of course obvious if one sits all of the different lengths next to one another along with a description of the different bond lengths in DNA, but some of the tubes are close enough in length that they were initially used interchangeably by the students. The model is accurate enough that if the wrong bond lengths are used for any pieces, it doesn't fit together correctly. That was a good teaching moment:-) Once we got that figured out, it was smooth sailing. The model is ideal for teaching everything from base pairing to major and minor grooves. Besides, it looks pretty cool in my office. I'd buy it again.
Thanks for the feedback. The instructions were written by the prof who designed the DNA model but they are nearly 20 years old & have some obvious shortcomings! The good news is we have engaged an exceptional high school teacher with exceptional students who are rewriting the material for us. Your concerns will be addressed in this iteration. As soon as it is done, we will announce this on the website & send copies to everyone who bought the model.