– What “writes” the information on DNA? And how does it adquire that information?
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DNA is a molecule: just a giant string of atoms in a specific configuration. The information is written by connecting the atoms together using various parts of a living cell.
There isn’t any information written on it, the structure of the molecule *is* the information.
DNA is a molecule: just a giant string of atoms in a specific configuration. The information is written by connecting the atoms together using various parts of a living cell.
There isn’t any information written on it, the structure of the molecule *is* the information.
The information is written onto the DNA, when the DNA is copied from a parent DNA. Ideally, it should never be written again after that.
New information appears from mistakes in the copying process, or from some environmental conditions: radiation, some chemicals, random rays from space, etc. Of course, this information is mostly random. It can be useless or bad, but sometimes it is good.
DNAs with bad information would then die out, because they cannot compete with other DNAs. DNAs with good information will get more opportunities to copy themselves – so that information will spread.
Ok. So here’s a good example. The Covid Vaccine!
The pfizer vaccine for Covid 19 is a bunch of bioengineered RNA copies that get injected into your bloodstream. Your cells pick them up (bioengineering magic involved) and then have a bunch of these RNA strands wandering around inside of them.
You have factory structures in your cells called Ribosomes. These read the RNA strand (like swiping a credit card) and use the instructions to build a protein (each 3-letter word on the strand adds another piece to the protein) (in this case the protein folds into an antigen that looks like a spike on the surface of the Covid virus.)
Now, like a lost cat poster, these RNA strands have a bunch of little tags on the end to tear off once construction is done. Because we want to make a LOT of covid spikes to train your immune system, there are a lot of tags. Each time the code is read, a tag gets torn off.
Once there are no more tags, the RNA strand gets thrown in the cellular trash bin.
As for how the DNA gets read… That’s [a bit more complicated] ( https://kurzgesagt.org/portfolio/crispr/) A protein structure will roll down your DNA and read one side of it. It will find a section that says “start copy here”, copy all of the data onto an RNA strand, and then release it into the wild once it hits a “stop copying here” codon.
There are also lots of segments that are commented out, (Histones), and only available to be read if certain conditions are met. (for more information, ask about epigenetics.)
Unless I misinterpreted your question. In which case the simple answer is sex and random mutations going back a billion years or so. (Also thieving bacteria and infectious viruses.)
The information is written onto the DNA, when the DNA is copied from a parent DNA. Ideally, it should never be written again after that.
New information appears from mistakes in the copying process, or from some environmental conditions: radiation, some chemicals, random rays from space, etc. Of course, this information is mostly random. It can be useless or bad, but sometimes it is good.
DNAs with bad information would then die out, because they cannot compete with other DNAs. DNAs with good information will get more opportunities to copy themselves – so that information will spread.
DNA is a kind of molecule called a polymer, meaning it is a long string made out of repeating subunits. DNA has 4 subunits, called nucleotides. The information stored in DNA is stored in the ordering, or sequence, of these nucleotides. In and of itself, this sequence is meaningless; what makes this stored information and not just a random string of nucleotides is something called the Central Dogma of Biology, which says that DNA is transcribed into RNA, which is then translated into proteins. Proteins our little molecular machines that do all of the things required to keep you alive: they move stuff around, made reactions happen, give your cells structure, flex muscles, etc. Proteins are another kind of polymer made out of 21 different kinds of amino acids (in humans), all combined together is a unique order for each specific protein.
Now, getting back to DNA. Your body ready DNA in three nucleotide chunks called codons; each codon corresponds to a single amino acid. This is how DNA sequence dictates proteins, by encoding for codons which are translated into amino acids. This ordering of amino acids is the information that is stored in DNA.
Now, your other question of how did this information get acquired is a bit of an open question in science. We don’t know how life originated, and we don’t know if we will ever know. Some significant experiments have shown that the conditions that existed in the early days of the planet Earth could have led to the formation of the required molecules just through the natural chemistry taking place at the time. These necessary molecules have also been found on meteorites, demonstrating that they form naturally just as a consequence of complicated chemistry. How did it all come to be? This is a complicated question for us, because currently life requires both DNA and proteins, but you need proteins to make DNA and you need DNA to make proteins! There are a few theories about how this came about, one major one is called the RNA world. It says that RNA actually came first, before either DNA or proteins. RNA is actually able to do everything that both DNA and proteins can do, just not quite as good as they do. So it’s theorized that we started with RNA only, and then evolved DNA and proteins. It’s
Ok. So here’s a good example. The Covid Vaccine!
The pfizer vaccine for Covid 19 is a bunch of bioengineered RNA copies that get injected into your bloodstream. Your cells pick them up (bioengineering magic involved) and then have a bunch of these RNA strands wandering around inside of them.
You have factory structures in your cells called Ribosomes. These read the RNA strand (like swiping a credit card) and use the instructions to build a protein (each 3-letter word on the strand adds another piece to the protein) (in this case the protein folds into an antigen that looks like a spike on the surface of the Covid virus.)
Now, like a lost cat poster, these RNA strands have a bunch of little tags on the end to tear off once construction is done. Because we want to make a LOT of covid spikes to train your immune system, there are a lot of tags. Each time the code is read, a tag gets torn off.
Once there are no more tags, the RNA strand gets thrown in the cellular trash bin.
As for how the DNA gets read… That’s [a bit more complicated] ( https://kurzgesagt.org/portfolio/crispr/) A protein structure will roll down your DNA and read one side of it. It will find a section that says “start copy here”, copy all of the data onto an RNA strand, and then release it into the wild once it hits a “stop copying here” codon.
There are also lots of segments that are commented out, (Histones), and only available to be read if certain conditions are met. (for more information, ask about epigenetics.)
Unless I misinterpreted your question. In which case the simple answer is sex and random mutations going back a billion years or so. (Also thieving bacteria and infectious viruses.)
DNA is a kind of molecule called a polymer, meaning it is a long string made out of repeating subunits. DNA has 4 subunits, called nucleotides. The information stored in DNA is stored in the ordering, or sequence, of these nucleotides. In and of itself, this sequence is meaningless; what makes this stored information and not just a random string of nucleotides is something called the Central Dogma of Biology, which says that DNA is transcribed into RNA, which is then translated into proteins. Proteins our little molecular machines that do all of the things required to keep you alive: they move stuff around, made reactions happen, give your cells structure, flex muscles, etc. Proteins are another kind of polymer made out of 21 different kinds of amino acids (in humans), all combined together is a unique order for each specific protein.
Now, getting back to DNA. Your body ready DNA in three nucleotide chunks called codons; each codon corresponds to a single amino acid. This is how DNA sequence dictates proteins, by encoding for codons which are translated into amino acids. This ordering of amino acids is the information that is stored in DNA.
Now, your other question of how did this information get acquired is a bit of an open question in science. We don’t know how life originated, and we don’t know if we will ever know. Some significant experiments have shown that the conditions that existed in the early days of the planet Earth could have led to the formation of the required molecules just through the natural chemistry taking place at the time. These necessary molecules have also been found on meteorites, demonstrating that they form naturally just as a consequence of complicated chemistry. How did it all come to be? This is a complicated question for us, because currently life requires both DNA and proteins, but you need proteins to make DNA and you need DNA to make proteins! There are a few theories about how this came about, one major one is called the RNA world. It says that RNA actually came first, before either DNA or proteins. RNA is actually able to do everything that both DNA and proteins can do, just not quite as good as they do. So it’s theorized that we started with RNA only, and then evolved DNA and proteins. It’s
Outside of some specific instances, DNA isn’t written to- it’s more like ROM. Mutations can change individual base pairs or rearrange sequences, and certain viruses can inject new DNA into an existing genome, but there’s not much in the way of a mechanism that writes DNA.
So where did all your DNA come from? Well, mutations and viruses primarily- mutations create genetic variation and natural selection preserves useful variations. A large portion of your DNA is slightly mutated copies of other genes in your genome. The process of meiosis, which creates sex cells, involves swapping genes between neighboring chromosomes. This occasionally introduces errors, like a chromosome picking up a second copy of a gene it already has, or even an entirely different version. These types of mutations increase the size of the genome over billions of years, while natural selection pares down useless or harmful effects.
Outside of some specific instances, DNA isn’t written to- it’s more like ROM. Mutations can change individual base pairs or rearrange sequences, and certain viruses can inject new DNA into an existing genome, but there’s not much in the way of a mechanism that writes DNA.
So where did all your DNA come from? Well, mutations and viruses primarily- mutations create genetic variation and natural selection preserves useful variations. A large portion of your DNA is slightly mutated copies of other genes in your genome. The process of meiosis, which creates sex cells, involves swapping genes between neighboring chromosomes. This occasionally introduces errors, like a chromosome picking up a second copy of a gene it already has, or even an entirely different version. These types of mutations increase the size of the genome over billions of years, while natural selection pares down useless or harmful effects.
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