Question
Chargaff studied DNA from a variety of sources. What didhe find that was different between the sources? What wassimilar? How did these findings contribute to the structureof DNA as we know it today?
Chargaff studied DNA from a variety of sources. What did he find that was different between the sources? What was similar? How did these findings contribute to the structure of DNA as we know it today?

Answers
When Chargaff was performing his experiments, the tetranucleotide hypothesis, which stated that DNA was composed of GACT nucleotide repeats, was the most widely accepted view of DNA's composition. How did Chargaff disprove this hypothesis?
According to the Tetra nuclear time. The hypothesis. Danny was made of equal amount of T g A. C nuclear tight. So that means the amount of because a equals G it was teach was see in Indiana Monica. But the data of each other's actually showed the otherwise. So his data showed that a equal to a tedx amount of G four to see, but 80 and D. C did not have the same amount. So this actually rejected or disapprove of the Tetra nucleotide hypothesis and replaced with a new theory that a pair was never tired. T and Nickel time Jeep here was nucleotides, see?
Jagoff famously found. But in samples of the night across species, the quantity of adenosine is approximately equal to the quantity of by main as far as number of molecules go. Was a mystery Passat seen ongoing? So how does this help us establish structure of DNA? Well, if this is true over many species and many samples, it's likely not a coincidence. There is probably some link between I mean I mean between scene, that's a currently ends, literally. So this helps us work out Barbara based parent systems that these boys came together.
So Irwin charge offs um research to the understanding of the structure of DNA was very significant. What he did is he discovered DNA is structure and its method of replication, and the rules for this is that he said that the number of wanting things in a DNA molecule will be equal to the number of side of scenes, and similarly, the number of adam means will be equal to the number of timings in the DNA molecule. So from this, you do the conclusion that see and G. Have hydrogen bonds between them and also A and T. Have hydrogen bonds between them.
So for this question, you do need to know a bit. Um, you would need to review or no a bit about shark crops, photographs rule. And of course, that's what it's asking about. Um, so if you don't know anything about shar graph going into this one again in the homework situation, go research it, um you know, test situation. You might be a little stuff because that's basically what this question is asking. So Shar graph basically discovered, um, at least starting out that there is a one toe one ratio between the perimeter deans to pure Eanes. So just from what I wrote right there, you might want to jump to an answer choice. But let's not do that quite yet. Um, he got a little bit more specific that we also have a one toe one relation. What? Ships of A's with teas. And, um, one there to to be a little more in a 1 to 1 with jeez and sees eso again. If you don't know anything about paragraphs, you might, you know, just get really confused. Um, but at least with knowing this, we know we can get rid of a couple of things. It's not about the individual molecules of DNA itself. So it's not saying that the phosphates and the sugars are equal to each other so we can get rid of choice a right away. Um, and then also, you know, with the little notes I made here, we can see a goes with t. G goes with C. So that's gonna allow us to get rid of choice. Be because in that when they're basically mismatches saying and a goes with a C instead, So this is going to be our correct pairing of these two. She's looking good. Now with what I wrote here, D could also look good. So in a testing situation, if you get something that's a little ambiguous like this, um, there are situations where the test question can actually be wrong, but you're still gonna probably want to try to answer the question. Anyway, For this one, I would actually choose choice seeing, because it's a bit more specific. Um, so this allows for a mismatch of the perimeter teens and the hearings. It could give us a situation that's more similar to like choice be, for example, or something, or some sort of mismatch. So since this one's not as specific just hearings and perimeter teens, I would go with a choice. See Is is the correct answer for this one, Andi. The reason why is because of that specificity. This is technically right as well, but this is giving us a little bit more information that makes it a better answer.