Messenger RNA (mRNA) is the RNA that carries information from DNA to the , the sites of protein synthesis () in the cell. The coding sequence of the mRNA determines the sequence in the that is produced. Many RNAs do not code for protein however (about 97% of the transcriptial output is non-protein-coding in eukaryotes ).
The RNA world hypothesis proposes that a world filled with life based on (RNA) predates the current world of life based on (DNA) and . RNA, which can both store information like DNA and act as an like proteins, may have supported cellular or pre-cellular life. Some hypotheses as to the present RNA-based catalysis and information storage as the first step in the evolution of cellular life.
The RNA world hypothesis places RNA at center-stage when life originated. This has been accompanied by many studies in the last ten years demonstrating important aspects of RNA function that were not previously known, and support the idea of a critical role for RNA in the functionality of life. In 2001, the RNA world hypothesis was given a major boost with the deciphering of the 3-dimensional structure of the , which revealed the key catalytic sites of ribosomes to be composed of RNA and for the proteins to hold no major structural role, and be of peripheral functional importance. Specifically, the formation of the peptide bond, the reaction that binds together into , is now known to be catalyzed by an residue in the : the ribosome is a . This finding suggests that RNA molecules were most likely capable of generating the first proteins. Other interesting discoveries demonstrating a role for RNA beyond a simple message or transfer molecule include the importance of small nuclear ribonucleoproteins () in the processing of pre-mRNA and and reverse transcription from RNA in in the maintenance of in the reaction.
The Hills had been forced to stop their car by a landed spaceship and its crew who compelled their captives to board their vessel. Their kidnappers were who seemed to be conducting a scientific investigation of earthlings. After performing a strange, bumbling but painful and degrading medical examination of the Hills (using technology which seems oddly archaic now, such as the chart recorders the Hills’ vital signs were plotted on), the alien’s leader showed Betty a star map. , who spoke English, told her that the map showed trade and exploration routes between stars and that our Sun and the aliens’ home star were marked on it (he pointed out roughly where he and his crew came from). The abducting aliens intended that the Hills would be unable to remember their ordeal, presumably using their advanced technology to block the couple’s memories. The dazed Hills were released and allowed to go on their way while the spaceship disappeared into the dark starry sky.
The RNA world hypothesis, if true, has important implications for the very definition of life. For the majority of the time following the elucidation of the structure of DNA by , life was considered as being largely defined in terms of DNA and proteins: DNA and proteins seemed to be the dominant macromolecules in the living cell, with RNA serving only to aid in creating proteins from the DNA blueprint.
I know little about legal standards for evidence but I didn’t think that sworn testimony alone was acceptable in law courts, in fact I believe eyewitness testimony has been shown to be highly unreliable, surely there has to be some form of corroboration.
by referring me to a book to “better understand the history and scientific background” of the Big Bang (and I stress again) THEORY, is condescending. What part of the radio telescope discovery of a background hum that I provided was inaccurate? I agree that people should know how this theory came about. Perhaps you should revisit your own source, and a few others, and I will agree to revisit the Dogon, if you can provide a source that doesn’t require that I store their junk on my computer (as the Bad Archaeology site requires). Or please, cut and paste the info from that site here in your response.
Your understanding of the Dogon people’s claimed astronomical knowledge is based on knowledge that I believe to be out of date. There is no evidence that they had any hard to obtain astronomical knowledge at all, see for example the .
My point about gravity addresses the same issue from the other end. Gravity is something we all can confirm, yet we do not fully understand it. This relates to the alien debate as a counter-argument example. A person does not need to be able to explain everything about aliens for their experience of them to be considered a real experience. I, nor the top astrophysicist, can convincingly explain what causes gravity, but we all can agree that it exists and we experience it.
Biology is not my field but I was under the impression that there no biologists expecting to observe the evolution of species, phyla or even domains in the lab because human timescales are too short so the failure to see these is not really evidence against evolutionary theory’s validity. I understand that there are sometimes excellent fossil records showing organisms transitioning into other forms (fish into land vertebrates and land mammals into whales are a couple of examples) so it seems reasonable to accept that biological evolution occurs. Similarly it is not surprising that we have not observed abiogenesis in lab experiments.
I agree we cannot “verify” the Big Bang but that does imply the concept was just invented which is what I think you implying. There is extensive evidence that the Universe is expanding and that expansion began 13.8 billion years ago. The details of the Big Bang event are pretty well unknowable but based on observations scientists (of the cosmic microwave background for example) can make informed speculations.
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Dear admin, your getting owned by Charles, who seems to be a truth seeker. You on the other hand are obviously not in search of truth but merely the safety of what your brain can comprehend. Because we know the lack of evidence of an occurrence does not disprove said occurrence, the truth seeker must be open to all possibilities that are yet to be disproven, you don’t sound open to these possibilities and even mock those who are as “wanting” to believe but many of the people who come forward are ridiculed and wish they could go back to their ignorant lives. Anyone who just wants to know the truth and had some common sense can read the conversation between you and Charles and read between the lines, where you are defending your position and Charles is simply stating facts about how science works and is constantly evolving. The only truth is we are very far from the truth. Cuddos to Charles, I thoroughly enjoyed your counter intelligence in this debate.