Check out other DNALC videos and animations: dnalc.cshl.edu/resources/animations/ Visit us in Cold Spring Harbor, Brooklyn, or Sleepy Hollow! 🧬Field trips dnalc.cshl.edu/programs/fieldtrips/index.html 🧬 Summer camps (virtual also available!) summercamps.dnalc.org
I'm impressed they managed to maintain such an accurate representation of this mechanism all the while keeping it simple enough to use as an educational tool... Good job dnalc!
Wow, the laws of nature, physics, chemistry, and lots of time. Thank you Darwin, for showing us how this can actually happen without a designer. If you only knew how right you were. And for those of you that prefer the designer explanation, please ask yourself what designed the designer, and that designer, and so on and so on. This is why intellectually honest people find this explanation terribly insufficient and weak. Get with it people, and remember that the amazing natural design depicted in this video is also loaded with imperfect design, and this imperfection serves to support evolution as much as anything else.
+hooooooman - Darwin knew nothing about genes, never mind the process of transcription or translation. However he put together a very strong theory, that of evolution by means of natural selection. The theory is very strong and has tonnes of evidence, but still doesn't answer the question of how the first life originally came into existence - how biological organisms came by through nothing but the play of chemistry, physics and chance. That is why many people believe in a creator, because it gives an answer to that question. Otherwise, how does it make sense that life can come from non-life? How can we get intelligence from no intelligence? How can we get complex laws and rules, from randomness?
+Sol Sammany but that´s the thing. Before, all evolution and biodiversity was the work of God, now that we understand it better the need for God moved to WHO started life. It´s the same with physics, and pretty much everything else, everytime something isn´t fully understood yet, people answear with God and when we are able to explain it, they move on to the next unanswered question. This is my problem with religion in science, if people leave the answear to God then there is no progress. To me God is just the easy way of not admiting that there are still things we cant explain and that we don´t understand everything . By the way im not criticizing religion as a whole, i just think that when it stands in the way of progress it´s a bad thing. But i can respect and appreciate the positive side of it too
The activator proteins can be found up or down stream from the transcription factors. A DNA bending protein (not seen in the video) actually bends the DNA and unites the activator proteins to the transcription factors and RNA polymerase at the promoter sequence of the gene. This unification is what forms the actual transcription initiation complex. That's when, in the video, you see the DNA molecule bending and then the RNA polymerase II ripping down the DNA.
helicase is the enzyme involved in the unzipping of the DNA molecule in DNA replication but transcription and translation are both processes involved inprotein synthesis. Hope this helps!
Matthew 5:17 Jebus 'the full-filler' said: "Do not think that I have come to abolish the Law...[I come to fulfill the law]" of my father, the genocidal, pestilential, jealous, petty, racist, sexist, vindictive, bloodthirsty, vengeful, spiteful, homophobic, murderer of men, women and children. From this it is clear why the Catholic Church ignored the atrocities committed by the Nazis during WW2. They had the evil teachings and role model of Jebus the Full-Filler; who sought to full-fill the law of his devil-god father.
@@ja31472 Totally, which means Martin Luther King Jr. was actually a devil-worshipper! All makes sense now. All that stuff about 'love being the answer to hate', must've just been a sick joke. Thanks for your wisdom lol
@@maxmarshall1260 You mean the "wisdom" of the old testament mass murdering god? Did King attempt to implement the old testament law or commands of his god? Thankfully not. He was tempered by atheist, anti-religious, enlightenment philosophies, as are many other believers who don't even realize where they got those sanity checks and filters that teach them how to cherry-pick their bible of bullshit, and to recognize a few moral diamonds buried in heaps of pig-excrement. There are (thankfully) only a few thousand Christians who are "old-school" fundamentalist and want to go back 5000 years. There are, unfortunately, about 5-10 million muslims who want hands, ears and eyes lopped off because their devil-god has never been tempered by an enlightenment or reformation.
Jonathan A. You have a very superficial knowledge of how old and New Testament theology mesh together. If you study it more closely, you will find that the God of the Old Testament is the same God of the New Testament. To sum it up (which is not really a great idea but I’ll do it anyway), imagine a father with five kids at ages 1 year old, 5 years old, 10 y.o, 16, and 25. The way he speaks to each child is different, and the way he teaches each child is different. But the father himself does not change. I think you get the point. I know that won’t answer the questions about genocide that you have, but to if you go to any mainstream church in America and ask the pastor to explain how God could command such things in OT times, I’m sure they would do their best to shed light on it. And I would like to point out that there are millions of people in the US who believe in the inerrancy of the scriptures, like me. And like you said, almost none of us want to “go back 5000 years”. It is a common teaching that the scriptures are totally trustworthy, but that doesn’t mean we go around killing people. Nowhere in the Bible is there a commandment for anyone today to kill anyone. Those were one-time only commands with specific purposes. Again, any decent pastor would love to spend all day talking with you about those specific cases if you wish. Otherwise, you haven’t given it a fair look.
And if you doubt my claim, please point me to a single bit of scripture that instructs me (being a modern day Christian) to kill someone. You won’t find anything. I know because I’ve read the whole thing, and I’m guessing you haven’t.
@lollipopswirl123 DNA polymerase and helicase are both enzymes that are onyl associated with DNA replication where as RNA polymerase is only associated with transcription. (RNA polymerase has elements within its structure that are similar to helicase but not the same)
Your explanation is good, but a little basic. RNAP is actually a group of subunits. Within the RNAP, there are exit channels, entry channels, and other interactions. I am looking for a more thorough explanation of the subunits and their individual interaction with DNA.
@phuturephunk RNA Pol eventually reaches something called a DNA terminator sequence (TAC), once it transcribes this region a specific protein (called Rho) or it can terminate by the RNA forming a hairpin loop on complimentary bases transcribed)
Is DNA only read and proteins made during mitosis or is DNA constantly being unzipped and rejoined at specific points along the molecule to make specific proteins when needed even when the cell isn't dividing? Are there molecules that can read the DNA sequence through the major/minor grooves of the molecule even before the DNA is unzipped?
How does the activator protein come in contact with the initiation complex if the enhancer region to which the protein binds can be thousand of base pairs away? Is the activator protein just really large?
According to scientific lecturers in Uni it knows were to start by having an innate attraction to the 'promotor' site (a set of DNA sequence that the RNA is attracted to). I don't know what they say for the 'stop' part.
Max Greyfeather It varies depending on temperature and target complexity....Read this: www.nobelprize.org/educational/medicine/dna/a/transcription/ It says 30/sec - but 10 is a rule of thumb - it varies...
Question about the 'unzipping' part of transcription: My biology teacher told me that DNA helicase does this, however my Chemistry teacher told me that RNA polymerase does this and helicase is only involved in replication. Who is correct? :'( they're both great teachers. EDIT: after a lot of googling it seems pretty much 50/50 to either helicase or polymerase - if anyone knows which one it actually is please let me know how you know lol and why lots of people are mistaken. Any info would be really appreciated!
Hi, great question! Transcription relies not only on RNA Polymerase, but on an entire team of proteins called the Initiation Complex. Part of the complex, TFIIH, has helicase activity, which is how the DNA unzips. It's a totally different helicase than the one involved in DNA replication. So essentially, both teachers are right and wrong haha. It's never simple in biology. this review has a section on the initiation complex: www.ncbi.nlm.nih.gov/pmc/articles/PMC1941834/ Good luck with your studies!
RNA polymerase has helicase activity in bacteria, and when transcribing mRNA in eukaryotic cells, TFIIH(one of the fractions of GTP) has it. In addition, TFIIE binds to the single stranded DNA.
Well, sometimes there is some miscommunication, transcription does have a non-zero error rate. But mostly, it works fine. And O'Reilly would be quite puzzled anyway.
I'm still pre-med so not the smartest but I was wondering if bidirectional promoters and gene loops would change this video? I'm having trouble understanding these two concepts
really hoping that this video would contain all of the complexes in RNA pol. Having a tough time figuring out where DNA enters, RNA leaves, and what is downstream vs. upstream. If anyone knows of a video or a site please help me out.
Where DNA enters what? it's in the nucleus and doesn't really move out in eukaryotes. RNA leaves the nucleus through the nuclear pores in eukaryotes. 'Downstream' refers to 'going towards the 3' end of DNA', whereas upstream refers to going to the 5' end of the DNA. For example, if i said that a certain transcription factor was upstream of the promotor, then that would mean that the transcription factor is more closer than the promotor to the 5' end
Could somebody please indentify the transcription factors? I think that the first one is TF2D and TF2B. The second, wich comes with the polymerase can be the TF2F. The other ones ares TF2E and TF2H. Am I right?
So I've recently read abt this 5' exonuclease called rat1 (Xrn2 in humans) tht is involved in transcriptional termination and does this by degrading the RNA pol. My gripe wth this is tht this exonuclease has to degrade the nascent RNA to intercept the RNA pol frm the 5' end. Can someone pls clarify this? Bc frm what I understand, the RNA will need to be made again frm scratch, which does not make sense as it defeats the point of transcription. Sorry tldr.
In case you are still interested. Termination of transcription and realease of the mRNA are two different steps. The mRNA is cut lose at the polyadenylation sequence. But the Polymerase keeps on transcribing. This newly transcribed RNA can be degraded by the exonuclease without the mRNA being affected.
I thought "helicase" unzipped the DNA strand, leaving it open for the RNA Polymerase to come in and complete the exposed strand, making the mRNA (see 1:18). I don't think this video is correct. Then again, I'm getting C's on my Molecular Cell Bio tests. :0/
Please don't do this. Althou this animation is named "advanced" it is still simplified. Just because you come across something complex in nature and don't understand the process, you cannot jump to the conclution that there 'must' be a god. If you have to lean to a supernatural explanation, don't go further than being a deist. And don't say that it's "mathematically impossible" when you don't yet know the formula. It is astounding how much of it that can be naturally explained.
Check out other DNALC videos and animations: dnalc.cshl.edu/resources/animations/
Visit us in Cold Spring Harbor, Brooklyn, or Sleepy Hollow!
🧬Field trips dnalc.cshl.edu/programs/fieldtrips/index.html
🧬 Summer camps (virtual also available!) summercamps.dnalc.org
"DNA makes RNA makes Protein." One of the most beautiful phrases that I know of in all of Biology.
Shut the fuck up man
Except it's not entirely true because many RNAs do not make proteins, but infact have regulatory roles or no role at all
I'm impressed they managed to maintain such an accurate representation of this mechanism all the while keeping it simple enough to use as an educational tool... Good job dnalc!
why can't every video have such good visual demonstrations!? pretty awesome what we're capable of
Wow that was one of the most dynamic animations I've seen of transcription
professor: what can you tell me about RNA polymerase
me: he ZOOM
LMAAAAAO
when the RNA went fast, i kept laughing.. I, lol
Brittany John Same😂😂
@@qurratulainnarmawala334 yes me too
hahahaha RNA go BRRRRR
NYOOM
Robber: hey you, give me the money in the register !!
Cashier: wait you look familiar, John is that you ?
Robber : 1:09
One of the most beautiful processes in the universe, IMHO.
That is some next level shit man.
This video really helped me understand a concept for my test coming up - thanks so much!
Wow, the laws of nature, physics, chemistry, and lots of time. Thank you Darwin, for showing us how this can actually happen without a designer. If you only knew how right you were.
And for those of you that prefer the designer explanation, please ask yourself what designed the designer, and that designer, and so on and so on. This is why intellectually honest people find this explanation terribly insufficient and weak. Get with it people, and remember that the amazing natural design depicted in this video is also loaded with imperfect design, and this imperfection serves to support evolution as much as anything else.
+hooooooman - Darwin knew nothing about genes, never mind the process of transcription or translation. However he put together a very strong theory, that of evolution by means of natural selection. The theory is very strong and has tonnes of evidence, but still doesn't answer the question of how the first life originally came into existence - how biological organisms came by through nothing but the play of chemistry, physics and chance. That is why many people believe in a creator, because it gives an answer to that question. Otherwise, how does it make sense that life can come from non-life? How can we get intelligence from no intelligence? How can we get complex laws and rules, from randomness?
+Sol Sammany but that´s the thing. Before, all evolution and biodiversity was the work of God, now that we understand it better the need for God moved to WHO started life. It´s the same with physics, and pretty much everything else, everytime something isn´t fully understood yet, people answear with God and when we are able to explain it, they move on to the next unanswered question.
This is my problem with religion in science, if people leave the answear to God then there is no progress. To me God is just the easy way of not admiting that there are still things we cant explain and that we don´t understand everything .
By the way im not criticizing religion as a whole, i just think that when it stands in the way of progress it´s a bad thing. But i can respect and appreciate the positive side of it too
This isnt proof of no god, you ignorant fuck.
@Rafael Silva Indeed and who is a human concept.
hooooooman So where is the beginning of a circle? How can a circle exist without a beginning and end? Lots of time?? Barahahaha..
Really nice animation - I have a much better understanding of distant gene enhancers now! Thanks
The activator proteins can be found up or down stream from the transcription factors. A DNA bending protein (not seen in the video) actually bends the DNA and unites the activator proteins to the transcription factors and RNA polymerase at the promoter sequence of the gene. This unification is what forms the actual transcription initiation complex. That's when, in the video, you see the DNA molecule bending and then the RNA polymerase II ripping down the DNA.
Yes! Exactly what I was looking for! Thank you DNA Learning Center!
No problem! We're glad it helped you.
This video helped me to understand our lesson, So Thanks to this.
This is very fantastic
helicase is the enzyme involved in the unzipping of the DNA molecule in DNA replication but transcription and translation are both processes involved inprotein synthesis. Hope this helps!
God's creations are so amazing!
@RoseSheeps You're not timewasting at all; we appreciate you letting us know if there is a problem! ;)
"I will praise You, for I am fearfully and wonderfully made; Marvelous are Your works, And that my soul knows very well." (Psalm 139:14 NKJ)
Matthew 5:17 Jebus 'the full-filler' said: "Do not think that I have come to abolish the Law...[I come to fulfill the law]" of my father, the genocidal, pestilential, jealous, petty, racist, sexist, vindictive, bloodthirsty, vengeful, spiteful, homophobic, murderer of men, women and children. From this it is clear why the Catholic Church ignored the atrocities committed by the Nazis during WW2. They had the evil teachings and role model of Jebus the Full-Filler; who sought to full-fill the law of his devil-god father.
@@ja31472 Totally, which means Martin Luther King Jr. was actually a devil-worshipper! All makes sense now. All that stuff about 'love being the answer to hate', must've just been a sick joke. Thanks for your wisdom lol
@@maxmarshall1260 You mean the "wisdom" of the old testament mass murdering god? Did King attempt to implement the old testament law or commands of his god? Thankfully not. He was tempered by atheist, anti-religious, enlightenment philosophies, as are many other believers who don't even realize where they got those sanity checks and filters that teach them how to cherry-pick their bible of bullshit, and to recognize a few moral diamonds buried in heaps of pig-excrement.
There are (thankfully) only a few thousand Christians who are "old-school" fundamentalist and want to go back 5000 years. There are, unfortunately, about 5-10 million muslims who want hands, ears and eyes lopped off because their devil-god has never been tempered by an enlightenment or reformation.
Jonathan A. You have a very superficial knowledge of how old and New Testament theology mesh together. If you study it more closely, you will find that the God of the Old Testament is the same God of the New Testament. To sum it up (which is not really a great idea but I’ll do it anyway), imagine a father with five kids at ages 1 year old, 5 years old, 10 y.o, 16, and 25. The way he speaks to each child is different, and the way he teaches each child is different. But the father himself does not change. I think you get the point. I know that won’t answer the questions about genocide that you have, but to if you go to any mainstream church in America and ask the pastor to explain how God could command such things in OT times, I’m sure they would do their best to shed light on it. And I would like to point out that there are millions of people in the US who believe in the inerrancy of the scriptures, like me. And like you said, almost none of us want to “go back 5000 years”. It is a common teaching that the scriptures are totally trustworthy, but that doesn’t mean we go around killing people. Nowhere in the Bible is there a commandment for anyone today to kill anyone. Those were one-time only commands with specific purposes. Again, any decent pastor would love to spend all day talking with you about those specific cases if you wish. Otherwise, you haven’t given it a fair look.
And if you doubt my claim, please point me to a single bit of scripture that instructs me (being a modern day Christian) to kill someone. You won’t find anything. I know because I’ve read the whole thing, and I’m guessing you haven’t.
Glad you liked it! :)
nice video, but what about prokaryotic transcription
@lollipopswirl123 DNA polymerase and helicase are both enzymes that are onyl associated with DNA replication where as RNA polymerase is only associated with transcription. (RNA polymerase has elements within its structure that are similar to helicase but not the same)
Beautiful.
Your beautiful :)
+Danny Koolaid shes with me you creep - get lost :p
@@GB3770 8 years later, you guys still together? how cute
Exactly what we needed👍👍❤️❤️
Thank you for adding CC!
Thank You. This is excellent explanation.
building little machines using atoms, that's ultimate nanotechnology and programing
0:26 scared the living daylights out of me.
When the zipper made contact with the activators that little thing just took off and I could imagine it going "WEEEEeeeeeeI'mcopying!" lol.
great animation
amazing! taking microbiology right now and this definitely helps.
Your explanation is good, but a little basic. RNAP is actually a group of subunits. Within the RNAP, there are exit channels, entry channels, and other interactions. I am looking for a more thorough explanation of the subunits and their individual interaction with DNA.
@phuturephunk RNA Pol eventually reaches something called a DNA terminator sequence (TAC), once it transcribes this region a specific protein (called Rho) or it can terminate by the RNA forming a hairpin loop on complimentary bases transcribed)
Is DNA only read and proteins made during mitosis or is DNA constantly being unzipped and rejoined at specific points along the molecule to make specific proteins when needed even when the cell isn't dividing? Are there molecules that can read the DNA sequence through the major/minor grooves of the molecule even before the DNA is unzipped?
this is the neatest thing
Well, might as well be a paradigm. But when first discribed (DNA -> RNA -> Protein) It was named "The centeral dogma of molecular biology".
Looks great, but I can only access the first half - it cuts out at 0:45.
Is it broken? or is it just my computer?
How does the RNA Polymerase "scrunch" the DNA to break free from the promoter region?
How does the activator protein come in contact with the initiation complex if the enhancer region to which the protein binds can be thousand of base pairs away? Is the activator protein just really large?
@RoseSheeps I just watched the video the whole way through with no errors; it sounds like a problem on your end unfortunately.
According to scientific lecturers in Uni it knows were to start by having an innate attraction to the 'promotor' site (a set of DNA sequence that the RNA is attracted to). I don't know what they say for the 'stop' part.
Is there a more advance one? Including things like TFIIA, TFIIB, TFIID, TFIIE, TFIIF, and TFIIH??
THANK YOU!
Good animation
How fast does RNA polymerase move in base pairs per second?
+Max Greyfeather 10/sec approx
Finally, someone answered this question. Thanks!
Max Greyfeather It varies depending on temperature and target complexity....Read this:
www.nobelprize.org/educational/medicine/dna/a/transcription/
It says 30/sec - but 10 is a rule of thumb - it varies...
FABULOUS
would the activator protein have to be downstream from the initiation complex?
I've watched both the simple and advanced versions of this and the only question I have is: How does it know when to stop transcribing?
sorry for the late reply x but I think when it reaches a stop codon
That was the coolest thing I've ever seen @.@
Question about the 'unzipping' part of transcription:
My biology teacher told me that DNA helicase does this,
however my Chemistry teacher told me that RNA polymerase does this and helicase is only involved in replication.
Who is correct? :'( they're both great teachers.
EDIT: after a lot of googling it seems pretty much 50/50 to either helicase or polymerase - if anyone knows which one it actually is please let me know how you know lol and why lots of people are mistaken.
Any info would be really appreciated!
Hi, great question! Transcription relies not only on RNA Polymerase, but on an entire team of proteins called the Initiation Complex. Part of the complex, TFIIH, has helicase activity, which is how the DNA unzips. It's a totally different helicase than the one involved in DNA replication.
So essentially, both teachers are right and wrong haha. It's never simple in biology.
this review has a section on the initiation complex:
www.ncbi.nlm.nih.gov/pmc/articles/PMC1941834/
Good luck with your studies!
@@ellihartig8298 Thank you!! I've struggled to find an answer to this so I really appreciate your help :)
RNA polymerase has helicase activity in bacteria, and when transcribing mRNA in eukaryotic cells, TFIIH(one of the fractions of GTP) has it. In addition, TFIIE binds to the single stranded DNA.
Nice video
Well, sometimes there is some miscommunication, transcription does have a non-zero error rate. But mostly, it works fine.
And O'Reilly would be quite puzzled anyway.
@Cierra Washington You're confusing translation for replication, the helix is only involved with replication.
Some people watch this incredibly complex process and believe it came about by chance!! 🤣
That thing is just a freakin machine. And that’s what we’re made of.
1:13 .. Roller Coaster Enzyme .. :P .. But really nice one! .. Thanks for the Vid. :)
it would help to have labels for the different parts of the simulation
awesome
I'm still pre-med so not the smartest but I was wondering if bidirectional promoters and gene loops would change this video? I'm having trouble understanding these two concepts
are you a doctor now
really hoping that this video would contain all of the complexes in RNA pol. Having a tough time figuring out where DNA enters, RNA leaves, and what is downstream vs. upstream. If anyone knows of a video or a site please help me out.
Where DNA enters what? it's in the nucleus and doesn't really move out in eukaryotes. RNA leaves the nucleus through the nuclear pores in eukaryotes. 'Downstream' refers to 'going towards the 3' end of DNA', whereas upstream refers to going to the 5' end of the DNA. For example, if i said that a certain transcription factor was upstream of the promotor, then that would mean that the transcription factor is more closer than the promotor to the 5' end
Where is the CTD of RNApol?
Subunits go in. RNA comes out. Never a miscommunication. You can't explain that!
عالی بود
Dr Adam Paige sent me here
Watch the videos on mutations and you'll see why that statement is wrong. Transcription is not a fail-proof mechanism.
How does it know where to start and stop on the DNA strand?
DNA helix opening to during transcription
how many ATPs are uses per 1000 bases in copying all the way to RNA?
Could somebody please indentify the transcription factors? I think that the first one is TF2D and TF2B. The second, wich comes with the polymerase can be the TF2F. The other ones ares TF2E and TF2H. Am I right?
i'm confused about what helicase, DNA polymerase, and RNA polymerase does. help pleasee?
So I've recently read abt this 5' exonuclease called rat1 (Xrn2 in humans) tht is involved in transcriptional termination and does this by degrading the RNA pol. My gripe wth this is tht this exonuclease has to degrade the nascent RNA to intercept the RNA pol frm the 5' end. Can someone pls clarify this? Bc frm what I understand, the RNA will need to be made again frm scratch, which does not make sense as it defeats the point of transcription. Sorry tldr.
In case you are still interested. Termination of transcription and realease of the mRNA are two different steps. The mRNA is cut lose at the polyadenylation sequence. But the Polymerase keeps on transcribing. This newly transcribed RNA can be degraded by the exonuclease without the mRNA being affected.
you actually believe this super complexity is random from nothing ahahahaha
well actually many errors are made, but the ratio to non-errors is low enough that proteins are worth making
Actually, there are miscommunications, and they can be explained.
OMG i could somehow understand this *feel so accomplished*
Why she stopped? Have stop codons, but why?
I thought "helicase" unzipped the DNA strand, leaving it open for the RNA Polymerase to come in and complete the exposed strand, making the mRNA (see 1:18). I don't think this video is correct. Then again, I'm getting C's on my Molecular Cell Bio tests. :0/
I'm confused with those "fancy" words.
Fancy ? lol
This is a lil confusing... could somebody explain?
The Mitochondria is the powerhouse of the cell.
Thats crazy
He really be zoomin tho
Now working on mine too... sorry for bothering/timewasting
That's really fucking fast. Where does the RNA polymerase get its energy from ?
It is still an open problem. It must be some very complex propulsion mechanism that does not use ATP
Astound all
if this is advanced, i need the European Extreme mode
Proof that aliens exist right here
Please don't do this. Althou this animation is named "advanced" it is still simplified. Just because you come across something complex in nature and don't understand the process, you cannot jump to the conclution that there 'must' be a god. If you have to lean to a supernatural explanation, don't go further than being a deist. And don't say that it's "mathematically impossible" when you don't yet know the formula. It is astounding how much of it that can be naturally explained.
And this happens WHERE? in our BODIES? wow 0.0
1:17 isn't it helicase that 'unzips' dna
No, helicase unzips in dna replication. RNA polymerase has built in helicase function.
@@thenicolaichristian Thanks for that I'm second year biotech now and realize I kinda need to freshen up on my first year stuff
MYEEEEH APPLE COMPUTERS
how the fuck did someone figure this shit out?
Oh okay. Nah I am not too good with that. I have touched on it tho.
@DTrinh09 explanation:chemistry.
im dead inside please help - leo
anyone here from steven ralphs class? pls like
I wouldn't say this is advanced. More like basic, at least if you are medicine student.