Molecular structure of DNA | Macromolecules | Biology | Khan Academy

[@jeromekrammes2031]

I feel like he is saying nucleotide like that just to frustrate me.

[@yourfavouritescepticx8969]

Jerome Krammes 🤣😂

[@SyrinSlava]

For some reason I flinch every time he says it

[@joefunnyguypesci6317]

n u c l a y o t i d e

[@KrystleOnline]

😂

[@nowhereman5119]

First class explanation. The repetitive speech style of the author actually helps to reinforce the ideas.

[@chinaibm]

If it's not too much trouble, could you guys include the links of other videos you talk about in the video's descriptions? Thanks! love the vids

[@miker7920]

This is awesome, I learn more in one video than during a semester at school

[@hipfire1920]

You actually get to learn it several times because of his repetitive speech

[@Sakarq]

Sal never disappoints!

[@mmaking8664]

+Sakarq NEVER

[@AleksandrSharashkin]

Thank you for explanation! Even I who had basic knowledge of biology and chemistry at school can easily understand 🙂 Thanks, you are my lifesaver

[@navinvenkat7551]

Sir, You missed a Hydrogen atom at the 4' carbon atom Love your videos by the way Thanks a lot

[@joyceong7221]

KHAN"s helping me pass my uni courses.

[@adkatadkut422]

deoxy, deoxy. ribonucleic, riiibo nucleic, riibo nucleic. acid. RIBONUCLEIC ACID. awesome vid btw

[@elektrofunkzz]

POWERFUL SAL KHAN

[@4tytude]

Thanks Sal! I have been wondering too why does the DNA is drawn with the O in the phosphate group having a negative charge, while it's being called an acid. Took me a while to find any reference addressing this. Thanks for clearing that up!

[@eluneslightreachesitszenit2048]

Thank ... Thank... you.. Thank you for the..... the ... vid... video.. the video.... thank you for the video... the video... thank you for the video. xD

[@rahulgattu825]

The best! hats of SAL!

[@kyleg4453]

Always praying for you guys, God bless

[@christandme1372]

That was so beautiful💗

[@CJ_Lucifer69]

No mashed potatoes in this video sadly just sugar based particles

[@sulimand.qotiba4862]

very helpful .. thank you

[@KIM-ml8vs]

thank you, but your repeating of words is really distracting

[@jenniferross4234]

Agreed, it's painful to listen to... one of the few reasons that I've avoided KA videos.

[@hipfire1920]

They do it so you will remember it better.

[@jaimea.9742]

@@jenniferross4234 yet you were here lol...find anyone else who explained it better?

[@liyanasohairi5418]

thank you khan academy

[@Horror528]

lmao if this is a high school chemistry in US it really changes my mind about y´alls education :DD

[@gamingbrotv]

Who else is watching this for online classes during Covid-19

[@TomAustinIII]

It would be great to have a similar breakdown on mitochondrial DNA.

[@ghidaaskar1227]

making life easier since i joined dentistry school. thank you!

[@bearpickle]

thanks for the great video- this really answered my question. now my mind is blown that this is actually going on at the base of our existence.

[@nadilmallikaarachchige3853]

wait so why cant thymine pair up with guanine, it looks like it can make a solid 2 bonds with guanine since the oxygen on guanine or the oxygen in thymine can bond with one of the middle hydrogens and the oxygen from thymine can pair with the hydrogen at the bottom of guanine, plus as proven at the end of the video where adenine and thymine have only 2 bonds to make a rung, so why cant thymine bond with guanine?

[@daviddet]

Whoa, I'm the first view on this video. Great video by the way! Love all your stuff!

[@hipfire1920]

does that mean you were first of like 300,000 students who were forced to watch this video?

[@sciencenerd7639]

Very nice

[@bikidas5029]

why purine and pyrimidine are numbered differently

[@freshely9309]

that hydrogen bond can sure get lost

[@starwarfan8342]

I still don't understand how hydrogen bonds can make proteins practically bulletproof when it's so easy to break hydrogen bonds.

[@travischung2800]

LIFE SAVERR

[@aliyadalo3812]

Thanks a lot!

[@m.shazainrashid1806]

A-One lecture.......

[@Rocky-me5cw]

Holy DNA!

[@nimishajain5645]

why is the other strand having a kind of inverted sugar

[@alecbrady6901]

DNA is made up of two antiparallel strands - they run parallel to each other but one is inverted or 'upside-down'. In Sal's depiction, the left strand is running 5' to 3' from top to bottom, and the right strand is the opposite to this and is running 3' to 5' from top to bottom. 5' and 3' just refer to the number carbon which is at the top and bottom of the chains. Hence, the other strand has an inverted sugar because it is upside down to the other strand. You can work out whether a strand is 5'->3' or 3'->5' by looking at the oxygen atom - the oxygen atoms always 'point' towards the 5' end of the strand.

[@hamedhosseini4938]

nerd

[@alecbrady6901]

That is the idea, considering the channel and all.

[@Walter5850]

So why can't Cytosine for example pair with Adenine? It would make N - H - N , N - H - N hydrogen connections, and it's oxygen could just hog a little hydrogen to himself from somewhere just like what happens with thymine? I know sometimes the nitrogenous bases can connect weirdly when mutations happen, but I'm just wondering on a chemical scale, what would be the reason that this just doesn't happen all the time?

[@minniekim2351]

It s weird. It is repetitive sometime there s subtitles, other time there no subtitle on KZbin. Does anyone know how to solve on the phone?

[@hipfire1920]

Non-autogenerated subtitles are put in manually by the creators or volunteers. Also, sometimes subtitles are turned off by the creator, if they choose.

[@rosepeterson3124]

Where is the methyl group in thymine?

[@wouldbfarmer2227]

Yep. I was wondering about this also. This is why we always double check our info. Is it possible he crossed up Cytosine with Thymine?

[@wouldbfarmer2227]

Correcting my statement. The Cytosine looks okay. He didn't label the CH3 as you stated. it should be off of the arm at the upper left by the arrow from the word 'Thymine'.

[@SuperSmith]

these videos would be half as long if they didn't color code every syllable.

[@arocks1234567]

Learn sugars Mem nitrogenous basis

[@zakirhossain9554]

sal is resque thanks a lot

[@thepulsiphyer]

Bro! It's pronounced NOO-cle-oh-tide! Get it right... oh my gosh it's almost as bad as someone saying "nucular" instead of "nuclear". **facepalm** so annoying and distracting!

[@EvilScientist]

370k views, and 45 comments... that's strange

[@hipfire1920]

It's all kids who were forced to watch the video but couldnt comment because they were blocked from doing so on their school email. Or they all watched it on Khan Academy's website, which doesnt give an option to comment

[@yssa1945]

if youre here bc of online classes say i

[@cj-dy7zq]

my brain isnt braining, sorry bye

[@maroofshabirmir6440]

Am I the only guy who couldn't understood it😠

[@jaimea.9742]

maybe you should stick to basic math...

[@maroofshabirmir6440]

@@jaimea.9742 I hate mathematics 😌