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    • #3201
      pankaaj
      Participant

      Why RNA has evolved as the genetic material before DNA?

    • #37189
      Poison
      Participant

      RNA is single strand. Isn’t it more possible to have a single stand first and a double strand second?

    • #37191
      2810712
      Participant

      Availability, fitness both are important. So, even if DNA is fitter , its initial availibility may not have been adequate. We can even regard availability as a quantitative fitness and other factor is qualitative fitness.
      The strand no. is also imp. but why not ssDNA be the first then??? RNA can also be double stranded, so why have DNA??? this tells that strand no. solely can’t explain this as its not the sole point of differece
      Seeing their complexities , lets see if we get some clue-

      This example can belong one of the two possibilities

      1.When evolution occurs from simple — to complex [ U—to–T] , complex can’t exists before simple. So even if complex is fitter simple has to exist first. But just existing doesn’t mean being involved in life ❗
      Acoordinlgy, RNA is just reqired to be there before DNA evolves.[ this depends on how many pathways that cangive us the molecules] But it may or may not be acting as agenetic material.

      2.When it comes to making a choice between two things [ U and T]with comparable complexiety, availability [besides fitness] will be an important constraint.In this case we can’t say that RNA has to be there before DNA evolved.It may or may not be present.
      Which one do you think the present example belongs to???

      Shrei

    • #37976
      pankaaj
      Participant

      see RNA has evovled first means that it was the first molecule to
      be used as an genetic material.
      I have found out following points-
      1)DNA changes its physical prop. when in
      a) Extreams of pH
      b)Heat
      c)Decrease in dielectric const. by some elements
      d)Exposure to Urea, Amides etc.

      Also in samples , it has been found that A & U combines quicker than T.
      I’m asking why it was evolved first & not why?

    • #38133
      2810712
      Participant

      Faster combinability [formability of RNA] is a qualitative fitness this indeed increases the availability of A-U sequence and thus affects the quantitative fitness this is how the qualitative fitness leads to natural selection.
      About dielectric const and urea & amide things i think RNA will also undergo some type of changes… but only those changes would tell the relative qualitative fitnesses of the NAs.

      Shrei

    • #38214
      Springer
      Participant
      quote Poison:

      RNA is single strand. Isn’t it more possible to have a single stand first and a double strand second?

      How, pray tell, could one strand of RNA form without intelligent input?

    • #38233
      Poison
      Participant

      Don’t change this into "intelligent Design vs. Evolution" kind of topic too. You already have one, enjoy with it.

    • #38242
      Springer
      Participant
      quote Poison:

      Don’t change this into “intelligent Design vs. Evolution” kind of topic too. You already have one, enjoy with it.

      Is that supposed to be a rational argument?

    • #38251
      mith
      Participant

      Our goal is to keep the forum tidy and useful. That’s why we don’t like having two threads on the same topic.

    • #38265
      alextemplet
      Participant

      Everything I have to say has already been said in the "Origin of Life" thread. Talk about deja vu . . . 🙄

    • #38318
      2810712
      Participant

      Bythe way -why is RNA still a genetic material in some Viruses can be a good question then. This may be thought as convergnt evo. when only the genetic material is considered.
      I mean this RNAs aren’t descendants of those RNAworld RNAs. Or they might be so:shock: .
      We should follow this-
      I think those who believe in intelligent creation should explain the significance of this chara. [ explain why is it intelligent/best possible]
      in their way and those who believe in evolution may explain their mechanism.

      hrushikesh

    • #38320
      Poison
      Participant
      quote Springer:

      quote Poison:

      Don’t change this into “intelligent Design vs. Evolution” kind of topic too. You already have one, enjoy with it.

      Is that supposed to be a rational argument?

      I think you need a reminder: THIS IS A BIOLOGY FORUM. We already LET you to have a topic for your idea. I advise you not to push your luck…

    • #38368
      AstusAleator
      Participant

      Now I’m no biochemist but here’s my unerstanding of the issue.
      It might not have been RNA (or more specifically ribozyme) as we recognize it today, but something very similar. The important thing about RNA is that it’s chemical properties allow it to self-replicate. Modern cellular replication requires a complex sequence of events involving proteins catalyzing the transcription of genetic material. Until the 60s it was thought that only proteins could catalyze the reproduction of genetic material, but scientific speculation of self-replicating RNA in the 60s led to the discovery of ribozymes in the 80s.
      Anyway, the theory (or at least one of them) is that these ribozymes or something similar formed out of the primordial soup and were subsequently enveloped in basic lipid-bilayer vessicles.
      That’s my understanding of the issue. Some biochemist is probably going to blow me out of the water now, but that’s ok.
      Dave

    • #38472
      b_d_41501
      Participant

      It’s amazing how Springer can turn every single thread into an ID debate. I vote that he needs to be banned!!!! His posts have littered the entire forum! lol 😆

    • #38593
      alextemplet
      Participant

      bd wrote:

      quote :

      It’s amazing how Springer can turn every single thread into an ID debate. I vote that he needs to be banned!!!! His posts have littered the entire forum! lol

      In all honesty, at first I enjoyed debating with Springer. It was at least thought provoking, but now it’s getting out of hand. So I think I’ll second that suggestion.

    • #38657
      Poison
      Participant

      No need for banning. We already warned him. And, I think he is clever enough to understand. 🙂

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