DNA | Biomolecules | MCAT | Khan Academy

Learn about DNA (deoxyribonucleic acid). Overview of DNA bases, complementary base pairing, and the structure of the double helix.

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[brcarter]

OMG thank you for mentioning Rosalind Franklind and Wilkins!!!! I think She ought to be nominated for a postumous nobel prize.

[Anna_Marie_Music]

Sal, you blessed mystical unicorn you, thank you for blessing us with your knowledge










- from every kid in america

[hat]

I like how MCAT biology is A-Level Biology in Uganda😭

[BULLSHXTYT]

You are crazy you know everything and teach so well...

[sciencenerd]

Very nice. I think it would be worth mentioning that the Hershey Chase experiment established that DNA is the genetic material, and this happened quite awhile before the Watson Crick discovery.

[giannatr]

Thank you!! This perfectly cleared everything up for me omg

[imadeitt]

harry you have your mother's eyes

[bbydiego]

You should go over RNA to complete the protein group with Uracil.

[biorainbows]

Please update the biology, chemistry etc playlists. It would be of such great help finding the videos :) Thanks

[SearchingAbsolute]

This has sparked more curiosity in me to understand, what are gene mutations and how they might be triggered/caused ; are gene mutations just a tool for natural selection !? ; Can gene mutations be "corrected" ; If gene mutations are the basis of all cancers, then rising cancer cases throughout the world hints at rising number of gene mutations ... ?

[brcarter]

Hey Sal, love all the video's and keep up the great work at Khan Academy! At around 12:13 you draw a sequence of basepairs to illustrate how bases always find a complementary nucleotide. I took the sequence you made up, and ran it through NCBI's free BLAST tool(Basic Local Alignment Search Tool, it's like a "google" search for known DNA sequences), and it turns out that random sequence of basepairs you used is known to exist in over 100 different DNA and mDNA sequences in over 25 different organisms, including the bacteria staphylococcus pyogenes, , macaca fascicularis (the crab-eating macaque), peromyscus maniculatus (the deer mouse) and solanum tuberosum (the common potato)!!!

[Punjabispitta]

Ahhhh man if you would have posted this like just 3 weeks ago, I would have gotten better than a C on my bio test. I can still use this for finals coming up but either way, I just want to say that you're the best Mr. Khan, I don't know what I'd do without you and Patrick JMT's video's. You've both helped me out so much through this semester. Y'all the real mvps :')

[lolakhalid]

Omg is this the noted anatomist doing the explanation?

[cloydpineda]

isn't its 3 billion base pairs? enlightened me please...

[masumarizvi]

in one of your other video you said human genome has 3 billion base pairs but in this one you told that there are 6 billion. which one is correct?

[mattgraves]

Yes, these are great for pre-med students but I am a 42 year old software engineer who is looking to move to bioinformatics, these add a beautiful richness to that work as well!

[JeevanBManoj]

Question, 6B is the total pairs in then entire human body isn’t it. The individual DNA strands in cells will give less pairs isn’t it. For example DNA in cells in eyes might have a different number of pairs than DNA in skin cell. Also does the 6B include replicas in multiple cells? I imagine two cells in skin will have same DNA information

[LuisGarcia-cqls]

He had me thinking he new what he was talking about for a while, until he pronounced it "jif" 12:26

[alejrandom]

I'm just a bunch of molecules tryikg to figure out how molecules work

[Contradel]

What is this D N & A you're talking about? And where can I get it?