Polymerase chain reaction (PCR) | Biomolecules | MCAT | Khan Academy

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Introduction to PCR (polymerase chain reaction).
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[@perpetualplantstudent]

We need a man like this in every molecular biology class, questioning LITERALLY everything. Because EVERYTHING needs a little further explanation Ms. Sawa!! Lol

[@nokwandandlovu1391]

I LOVE THIS WAY OF EXPLAINING ......GETTING SOMEONE WHO KNOWS AND ONE WHO DOESN'T KNOW THAT WELL

[@jessemaretzki8002]

Hi Sal! I am studying pursuing my undergraduate studying molecular biology with a presentation on Real time PCR tomorrow. I really think this is an amazing process especially with respect to the forensic applications! Thanks for this video, it kind of summed up everything I have already covered so I feel really ready! Khan academy has been great since 8th grade and I am still using it now studying for my MCAT so thank you from the bottom of my heart!

[@TsangChiYim]

I am a layman but I can still understand PCR completely through this awesome video. Thank you Khan Academy!!!

[@zenaguerrero913]

Always love how you guys break down the extent of knowledge to be understood :D

[@jo_west4871]

Exactly.

[@machariawanjagi5353]

precisely

[@milo7167]

Omg this is guy is awesome how clear he is in his explanation thank you thank you thank you comme to teach to our community college in Glendale Cali please!!!!

[@paolamacario9317]

love this.. have a test this friday and it was hard to understand my textbook

[@ariatnaserrano8551]

Literally all the questions I had you answered wow thanks.

[@darisberdavis]

Every video that I see with this man’s voice…. I automatically know that I will learn something ❤. Love it

[@nathanielscreativecollecti6392]

Best explanation I have seen so far! Yeah Khan Academy!

[@ShonMardani]

It is hard to understand PCR, no wonder after many years and millions of lectures, we can't make sense of it.

[@valorijoy900]

To be clear, you do NOT exclusively have to use Taq polymerase. My lab uses Phusion. What matters is that it is thermostable.

[@TheLizardWizard1]

Wow thank you for the lightbulb moment

[@netad7771]

Thanks so much sir ❤❤

[@makemelotsotetsi8047]

fascinating..I am studying Botany at the university of the free state, this video was really helpfull

[@shakilarasa2920]

Thank you I have a question What is the purpose of the positive and negative control in the PCR reaction?

[@craftsandscience860]

shakila rasa the negative control to detect if there is any DNA contaminant in my PCR reaction mixture. After the PCR reaction, the negative control should not produce any band on the gel electrophoresis. The positive control is the control that contain a piece of DNA that will be replicated using my primers and produce a bands, it is just to check that there is nothing wrong with my PCR reaction steps, denaturation, annealing and extension.

[@Fathima-jl4zu]

Helped!

[@updateofficial5893]

i hav understood thanks man

[@kmaster57]

I don’t know if the video mentions it but you can also use pcr to generate multiple copies of a mutated strand by introducing a primer containing a mutant base then favoring only mutant by introducing endonuclease to remove parent strand (mostly like nucleases selecting methylated strands) then repeatly coloniezes bacteria until you got a mutant

[@marchenkogirl]

I had such a hard time understanding this material until now... thank you!

[@ejikechristianogadinma2223]

I had a great time listening and watching 👍

[@khayalamimahlalela7904]

Glad and grateful to witness your passion in sharing your knowledge. Bless up!!

[@mayeshasama6158]

That was really good... Thank you

[@SumanYadav-ln7uy]

Thank you

[@inesberrios4911]

THIS VIDEO SAVED ME

[@sciencenerd7639]

Great video, thanks

[@manihriilawrence8430]

One of the best 👍💯

[@djsmith2235]

Can someone explain to why it must be cooled afterwards separating the DNA? And then reheated for that last step?

[@ZVMed]

Thank you, this helped a lot!

[@woofpuppy]

*Important video*

[@gregvisioninfosoft]

i'm a newbie for this entire topic. its clear from this description that only a 'small fragment' (if this is the proper term) of DNA is able to be 'amplified' using this method. but for my understanding, what if the goal is to amplify the ENTIRE DNA sequence (say as in 3 billion base pairs of a human genome). can PCR still be successful to do this - if not, why (and what alternative method would be used)? and if yes, is there anything ''different' about the process for an entire sequence? Thanks in advance, for any insights...

[@asbinojha]

Thank you so much for all the contribution. Much improvement. 😊

[@rmn12322]

soo helpful, Thank you !!

[@nathannathan2814]

How are the nucleotides added and in what form?

[@roseleelauper1193]

Excellent, thank you

[@travislong1234]

We use Pcr at out Food Micro Lab..to make sure food is safe for public

[@hangantrann]

I have a question, why don't we just put the separate enzyme in instead of heating it up?

[@magicthegatherer6903]

The polymerase is from Yellowstone and the guy who discovered it took it without permission. When the patent was sold for 300 million, he gave no royalties to the park service

[@grim8391]

That's tuff

[@swindler1570]

Thermus aquaticus*

[@crazybull7282]

Both thermophilus and thermus are used.

[@atillaogan3654]

@@crazybull7282 thermus thermophilus is a seperate species

[@Wfb_DVM]

How do you know what exact region you want to make copies of from the original template?

[@slenderman4378]

Sanger sequencing to determine the nucleotide sequence and primers which attach to that specific sequence where you want to make copies

[@ThatGuyDownInThe]

I love this stuff so much WHAT

[@iftkharahmad4511]

Can u plz subtitle ur videos, as you have done on google.

[@6boris9]

Can I find primers on black market?

[@aizaali2988]

Why all the great teachers on KZbin .Why do we need to pay for college by providing us with such an average teaching?

[@aleksandregvaramia5174]

She sounds like Alexandria Ocasio-Cortez

[@athenajohnston]

Great video - thanks Sal!!

[@atorbcurious6979]

how do you select the right primer when you want to detect a new virus (in case of the first ever testing for that supposedly new virus) ? How do we know about the DNA- when we are trying to figure out if this is a new unknown virus?

[@biologywithannie]

Primers can be designed only if the sequence is known. So for detecting a new virus, the first step would be to sequence a sample of it isolated from a patient (using techniques like sanger sequencing) and confirm that it is a new strain of virus. Then you can design the primers by using a sequence that is unique to that strain. Now, you can test if this virus is present in the population by PCR. Only if that unique sequence is present in the patient's sample, will the PCR work and amplify DNA. Hope this helps.

[@nnnn-fr8rx]

Why do we need to cool it down for the nucleotides to bind with the DNA?

[@angeloquimoyog6448]

I think Taq polymerase and primer function at a cooler temperature.

[@maratmasry]

Wouldn't it have something to do with proteins denaturing under high temperatures? You would have to cool them down first

[@kisumfan5754]

Exactly PCR

[@unglue7835]

hey y'all. just curious but what's the difference between this channel and khanacademymedicine?

[@taniamukherjee8590]

This for those studying for the MCAT to get into med school, and the other is for those in med school studying for their classes. Just technicality but yeah some of the mcat videos dont cover things beyond the scope of the mcat

[@محمدحسينالصيدلي]

awesome

[@sanat1102]

Can a primer which has been involved in one cycle be utilised again in another cycle? Or is it necessary that a fresh primer is necessary?

[@tartanhandbag]

the primer becomes part of the new complementary sequence, so it's not "free", as it were, to go float off and bind to some other DNA strand. in that sense, it has no choice; once it binds it is fixed there. as the cycles go on, eventually the amount of primer (as well as dNTPs) get depleted.

[@kurtiscollins9814]

This isn't the best explanation of PCR, but it helps summarize.

[@Rysussybaka]

new-KLEE-yo-tides or new-CLAY-yo-tides?

[@IndieKanya]

can't we clone the dna fragment in a suitable host using vector??...

[@mmaking8664]

You can. Transfect bacteria with DNA and the bacteria itself will replicate the DNA

[@mostirreverent]

Why are primers made for both sense AND antisense DNA targets.

[@craftsandscience860]

Greg Fox to replicate both of the DNA strand, sense and antisense. If you design primers for only the DNA sense strand for example, it will replicate only the DNA sense strand making the number of copies of this strand higher than the DNA antisense strand

[@mostirreverent]

Thanks, I came to realize that a few days after :)

[@o2xb]

its to make 2 copies and not just one , therefore making it super efficient!!

[@dannyreed2887]

Thermos Aquaticus found in hot tubes in Yellowstone

[@samee_vov]

I Don't Just love these videos as they help with Mathematics but the person who does the videos sounds alot like the quite popular PokeMon KZbin +TheMunchingOrange .

[@platinum-or3y]

Omg First

[@NoyumiAo]

yasss bio

[@lauriedelgado8395]

how does RT PCR work?

[@SuperHulk1989]

It's the same just add prime and reverse transcriptase to your RNA you will get one DNA strand and then use the same steps in the video...

[@mmcrgh]

How come you have an MCAT tutor that hasn't made PCR before?

[@josesomohano6118]

Same way I can teach you how to do CPR without actually ever having to perform it on live person.

[@manuelberenguerrojas7271]

I did PCR in my second year of college. In four years I’ve done it over 5 times.

[@UdyKumra]

He pronounces nucleotides wrong. :/

[@cheewin1017]

i ship yall

[@anvisamanta7606]

♡

[@4shotBballTrickShots]

My dad says that this is actually the correct way to pronounce "nucleotides". And I think he knows what he is talking about because he has a BA in Genetics

[@RxlredE]

Who is the professor here guy or the girl😂

[@PLF...]

Info is good, but terribly drawn... The difference between the shortened and original strand is almost non-existing. Make it shorter, use another color or something along those lines.

[@earthworm-filledstomachbyc4254]

Seek Christ Jesus YHVH

[@09ak31]

FORTNITE OR FAIL TEST

[@Deadbond1]

:)

[@11z10]

I'm cringing at how he pronounces "nucleotides."

[@ss-nu8xx]

Yeah keep focusing on the unintelligent aspects. Low IQ

[@tomazkopac1075]

Her voice and use of words is really annoying (as she would talk to kids), exAAAActly...

[@SkySky-wk9vv]

wow amazing!!! thank you