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MITx Bio
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Biology educational videos produced by MITx Biology - a division of the Massachusetts Institute of Technology Department of Biology. Our videos can also be found in our free MITx courses published on edx.org! Join us!
DNA Topology
Learn more through our free-to-audit, open online #728x Molecular Biology course series: bit.ly/MITxMolBio1
Or start with #700x introductory biology: bit.ly/700xBio Also check out #703x Genetics (bit.ly/GeneticsPart1) See all of our free-to-audit courses on our website: bit.ly/MITxBioCourses
Video created by Ceri Riley for MITx 7.28.1x Molecular Biology: DNA Replication & Repair, a MOOC published on edX. Copyright MIT, all rights reserved.
An exploration of the complicated world of DNA topology: how DNA is described with linking number, twist, and writhe, and how topoisomerases and gyrases alter these properties.
Or start with #700x introductory biology: bit.ly/700xBio Also check out #703x Genetics (bit.ly/GeneticsPart1) See all of our free-to-audit courses on our website: bit.ly/MITxBioCourses
Video created by Ceri Riley for MITx 7.28.1x Molecular Biology: DNA Replication & Repair, a MOOC published on edX. Copyright MIT, all rights reserved.
An exploration of the complicated world of DNA topology: how DNA is described with linking number, twist, and writhe, and how topoisomerases and gyrases alter these properties.
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Відео
Molecular Biology Assays: multiplicity of molecules
Переглядів 7 тис.8 років тому
To learn more, join our 7.28x Molecular Biology course bit.ly/MITxMolBio1 You're performing an assay on a sample of DNA in the lab - have you ever stopped to think how many molecules of that DNA you're using in your assay? Are you working with just one DNA molecule, or millions? billions? trillions? Created by Sera Thornton for MITx 7.28.1x Molecular Biology: DNA Replication & Repair. Copyright...
Cell Cycle Terms
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This video gives a basic overview of the common terms used to describe the cell cycle for a molecular biology course. To learn more, join our free-audit, open online 7.28x Molecular Biology courses. bit.ly/MITxMolBio1 Created by Ceri Riley with guidance from Sera Thornton, Mary Ellen Wiltrout, and Stephen Bell. (c) 2015 Massachusetts Institute of Technology. All rights reserved.
Cell Cycle
Переглядів 20 тис.8 років тому
This video gives a basic overview of the cell cycle for a molecular biology course. To learn more, join our free-audit, open online 7.28x Molecular Biology courses. bit.ly/MITxMolBio1 This video was created for MITx 7.28.1x Molecular Biology: DNA Replication & Repair, offered on edX. Created by Ceri Riley with guidance from Sera Thornton, Mary Ellen Wiltrout, and Stephen Bell. (c) 2015 Massachu...
The Structure of DNA
Переглядів 3,4 млн9 років тому
An exploration of the structure of deoxyribonucleic acid, or DNA. If you want to learn more, join our free-to-audit, open online #700x Introduction to Biology course (bit.ly/700xBio) or our #703x Genetics (bit.ly/GeneticsPart1) Also try #705x Biochemistry. (bit.ly/705xBiochem) or our advanced #728x Molecular Biology course (bit.ly/MITxMolBio1). Learn more about our work: bit.ly/MITxBioCourses T...
Cellular Respiration and Fermentation
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Created by MIT undergraduate student Francesca Cicileo. If you want to learn more Introductory Biology content, join our free MITx 7.00x Introduction to Biology course. goo.gl/KEbNJ6
students attendance here🙋♀️.....specially class 12th
Me basically doing masters in this thing in 8th grade✋🏼:
Thank you 😊
❤❤❤❤❤❤
3
As someone who did not take a single chemistry course, I wish to ask a question (after looking for a satisfactory answer online w/o success). What significance do the different geometric shapes play and how did they come to be chosen. Is each a scientific standard for the position shown in the video? Is there a reference chart of shapes used available? Or a link to an article and/or site that might explain it, >simply<?
I'm not quite sure what you mean. The pentagons and hexagons represent the shapes of the molecules. Their corners are where the atoms lie and the edges represent the chemical bonds between the atoms. Their significance lies in that fact that they represent the shape of the molecules. In the case of ribose, the structure is actually more 3-dimensional but it's represented as a pentagon because in reality there are 5 atoms there connected to eachother like the corners of a pentagon. There are molecules that have little triangles in them and ones with squares and ones with pentagon and so on and so forth. So when we draw them, we draw those shapes. The only "shape" they use that doesn't really have anthing to do with the way the atoms are connected are the circles they use to represent the phosphate groups. They show the actual atoms in there at 2:03. It's not like "blue circle" is a universal symbol for "phosphate group" or something like that. There's no "scientific standard" or "reference chart". Whoever made the graphics thought "hmm, I need some kind of symbol to indicate that there's something here, this blue circle will do fine (and kind of match the color chosen for the ribose)" If I completely misunderstood your question or you would like me to explain anything further, let me know
@@lunkel8108 are the molecules actually shaped as displayed, or is it simply a way to represent how many and where connections are made? Depends how you read "pentagons and hexagons represent the shapes of the molecules" (ref.) It's difficult to adequately convey the questions in my mind, having never liked the sciences enough to learn more than I did in required classes. So, please forgive my ignorance.... but, I certainly thank you for responding.
@@mnrd34 Yes, the molecules are really those shapes, with 2 (maybe 3) caveats: 1) This is a pretty minor one: the side lengths and angles are commonly not all perfectly equal as in a regular pentagon/hexagon/etc. If the ring only consist of one type of atom (e.g. all carbon) (and all of the bonds are of the same type), then all of the lengths and angles will be perfectly regular. If you introduce other atoms such as nitrogen (in the nucleobases) or oxygen (in the sugar), then some atoms end up taking up more space than others and pulling on eachother by different amounts, resulting in bond lengths and angles that differ by a few percent from what you would observe in a perfect regular polygon. But in general, they're pretty approximations. 2) This is a bigger point. In general, molecules are not flat. They have more complicated 3D conformations. The nucleobases are an exception. If you look at their structures, you might notice that every second bond is a double bond. This gives rise to a phenomenon called "aromaticity" that leads to them being completely flat (within the ring structures). The classic example of an aromatic molecule is benzene, which is a perfectly flat, perfectly regular hexagon of carbon atoms. But if you don't see double bonds between every second pair of atoms, rings of atoms are 3D. The (deoxy)ribose here is a good example. If you search for "2' endo vs 3' endo" or something like that, you'll see the two conformations it can take. For 6-membered rings, look up "chair conformation" to see the actual structure. 3) You could argue about what it really means for a molecule to "look like" something. Here we're just talking about the relative position of each atom. Connected to this, but more complicated, is what the electrons between and around those atoms are doing and how they are distributed. If you'd look at the electron density instead of the nuclear positions, you would end up with a slightly different picture. Again, if you have any more questions, I'd be happy to help
@@lunkel8108 ...off to read and learn! ...to return, as needed, with questions. Thank you so much.
Strange that the average comment is amazed and delighted at the video illustration and not the complexity of the molecule.
This video is very good. students who shy in class and cant ask there question ❤
Since when I was in Intermediate School, I was interested in DNA. That's may be the reason why I feel intrigued in this video. By watching this video, I learned that DNA has its own order in its lines and each lines are called "Watson" and "Crick". There's must be other interesting secrets about DNA I might feel happy to understand . I hope I can see them soon not in the vague but in the vivid color. 10818 안재율
When I studied the theory except seeing animation ,I didn't understand anything. But when I saw ur animation, I understood greatly.thanks a lot.nice presentation ❤❤
Who created this wonderful molecule???
If you want know pleas read Quran and you will find it I was like you but finally l had found the reality the truth
OMG! This is the best DNA explaination video I've seen! I feel like after such a visualization I'll never forget it. You really helped me a lot to finally understand it. And you've included hydrogen bonds and pi-pi ones, reason behind bases pairing like that and other details I had no idea about. Thank you so much! Love from Russia
This is awsome❤❤❤
Thanks!
Love from Bangladesh 🇧🇩🇧🇩
Thanks mam❤ nice video
❤
So basically we can't live without a sugar daddy
My name is MANNY LUNASIN IS BEWITCH AFFECTS OUR DNA😅?IF IT'S TRUE THEN I WANT TO BECOME BILL GATES HAHA🤦♂️😅
Is vomiting or saliva swallowing during mind dirty tricks affects our genetic,,what about the world give us only one job and that is making poop into charcoal and electricity just to conserve our invoronment?
طلاب ست حراب🥹🔥
+
This is impressive, the way you explained it and the animation are amazing, I'm learning about DNA recently so watching this was fun and helpful.
مخابرات 💀
Thank you very much. It was really helpful.
Thanks ❤
Amazing Animation and a wonderful explanation, thanks to this wonderful animation🙌!
nice video
I have a 20 seconds short video on the full DNA structure in my UA-cam channel, do give it a watch
ua-cam.com/video/tdew2T_431Q/v-deo.htmlsi=VFylsJxWMn6K1jnj
انا مفهمتش حاجة يا سيد😭😭
Thanks
Fantastic! More puzzle pieces!
This a really good video. Some more pieces of the puzzle fall into place.
Glad you liked it! Check out our course as well. bit.ly/700xBio
jazakallah
A single thanks is not enough. Lots of love ❤❤❤❤
How did the writhe number increased by 2 by type 2 topoisomerase???
Initially, the dna was negatively supercoiled with a LEFT handed turn. So by convention, W=-1. Topoisomerase 2 cut both strands and passed the dna through the gap thus created. Now the dna became positively supercoiled with one RIGHT handed turn. So W=+1. So from -1 to +1, the value of W increased by 2.
Dna atgc אדני שדי
Not gonna lie that was 7 hours of lecture in that 7 mins
ua-cam.com/video/1gXaj0fvoVw/v-deo.htmlsi=fC0mLtH4ICQQUJpa
best one❤
Thaaaaaaaaaank you very much, you can’t imagine how you helped me🫡
Glad to hear it. Check out our course, too. bit.ly/700xBio
Incredibly useful video. Thanks!
Try our course as well. bit.ly/700xBio
Helpful video 💖
🎯 Key Takeaways for quick navigation: 00:00 🧬 DNA is deoxyribonucleic acid, and this video explores its key structural features and their importance for function. 00:29 🧬 Double-stranded DNA forms a double helix, with the most common form being B-form DNA. 00:58 🧬 Each DNA strand consists of polynucleotides made up of nucleotides with three components: a five-carbon sugar, a phosphate group, and one of four nitrogenous bases. 01:25 🧬 Nucleotides in DNA are deoxynucleotides, and they bond through phosphodiester bonds, forming the DNA backbone with a 5' to 3' directionality. 02:23 🧬 DNA strands have different orientations, with one being 5' to 3' and the other 3' to 5'. 02:50 🧬 DNA strands interact through non-covalent hydrogen bonds between the bases, forming base pairs that are specific in their pairing. 03:47 🧬 DNA base pairs include pyrimidines (thymine and cytosine) and purines (adenine and guanine), which form hydrogen bonds with specific geometry. 04:16 🧬 The DNA double helix is highly regular, with each turn comprising approximately ten base pairs, and pi-pi interactions between bases stabilize the structure. 04:44 🧬 The DNA double helix features major and minor grooves that act as recognition and binding sites for proteins, allowing sequence-specific and non-sequence-specific interactions. 05:14 🧬 Understanding DNA's structural features helps explain its function and how proteins interact with it for various tasks. Made with HARPA AI
Request UA-cam not to keep 'dislike' immediately after 'Like', this increases chances of misclick.
very cool video
1:40 If like me you are confused because the C atoms in the sugar are number counterclockwise, while perhaps you expected them to be clockwise, image to make the same drawing with a marker on glass. Now if you look at the glass from one side, you get the C atoms numbered counterclockwise, and the 5' to 3' prime direction going left to right (on the top polymer); if you look at it from the other side, you get the C atoms numbered clockwise and the 5' to 3' direction going right to left!
Great video
ua-cam.com/video/IEWHhrHiiTY/v-deo.html
Most important topic dna
my bio teacher send me here ToT
Thank you so much! This perfect animation certainly deserves appreciation :)