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Nucleotides are made up of a heterocyclic nitrogenous base, a sugar (only ribose or deoxyribose), and a phosphate. In nucleotides, obviously the nitrogenous base matters as its variations dictate the production of certain amino acids, and the sugar can only be ribose (in RNA) or deoxyribose (in DNA), but does the type of phosphate matter? I've seen that a nucleoside describes the nitrogenous base and the sugar alone, and there are nucleoside monophosphates, nucleoside diphosphates and nucleoside triphosphates.

Do these three variations differentiate; when it dictating the production of amino acids; when looking at any sort physical variation; in any sort of way; or are all three just the same as each other?? Also, do all of the phosphates have to look like this? (https://en.wikipedia.org/wiki/File:Phosphate-group.png). Or can they look like this (https://en.wikipedia.org/wiki/File:Phosphodiester-group.png). If they can look like the second image, then similarly to the question above, does it make any difference?

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closed as too broad by Remi.b, David, MattDMo, kmm, AliceD Jan 1 '17 at 19:48

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

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    $\begingroup$ Hi, welcome to the Biology Stack Exchange! Interesting question, do you think you could try and distill it down to one question? I'm not sure if you're trying to ask about phosphate (of which there is only one: PO4) or asking about nucleotides. $\endgroup$ – kingfishersfire Dec 31 '16 at 18:40
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    $\begingroup$ I have cleaned up your title and removed irrelevant tags. You are asking a very basic chemical question about chemical structures, the only complication of which is the ionization of the phosphate at physiological pH. Read and understand the WIkipedia or Berg et al (NCBI Bookshelf) pages about the structure of nuceotides, phosphate, and nucleic acids and you will be able to answer your own question, which will no doubt be put on hold shortly. $\endgroup$ – David Dec 31 '16 at 21:13
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    $\begingroup$ 1. Do the differentiations of possible phosphates (e.g. mono-,di-,tri-, isomers) as components of a nucleotide affect the function of that nucleotide? $\endgroup$ – Lucas Dyson-Diaz Dec 31 '16 at 21:45
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    $\begingroup$ 2. Is it often that nucleotides are found with more than one regular phosphate group (first link in question) as a component? $\endgroup$ – Lucas Dyson-Diaz Dec 31 '16 at 21:47
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    $\begingroup$ @MattDMo (to the first question) How so? How does the phosphate group(s) it affect the nucleotide? $\endgroup$ – Lucas Dyson-Diaz Jan 1 '17 at 13:11
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Well it turns out that when nucleotides are bonded together in a strand of DNA/RNA (nucleic acid) they ALWAYS HAVE only one phosphate group attached to their nucleoside (nucleoside = sugar + nitrogenous base (without phosphate)).

However, when they are by themselves, they are more often found with two or three phosphate groups as oppose to just the one. For this reason, the definition of a nucleotide is often misunderstood as it refers to containing one OR MORE phosphates, in reality, the official definition of a nucleotide states that only one phosphate group is present...

An example of a (so-called) "nucleotide" is ATP (adenosine triphosphate); it follows all of the rules that the misunderstood definition of a nucleotide states (these are; a nitrogenous base (adenine); a pentose sugar (ribose); and one "OR MORE" phosphate groups (triphosphate)). However, according to the official definition of a nucleotide, it is not, in fact, a nucleotide! It is instead considered a 'nucleoside triphosphate', since it is a nucleoside. with three phosphate groups (it is also a nucleotide with two additional phosphate groups, but I guess 'nucleotide-with-a-diphosphate' attachment doesn't roll off the tongue so well as nucleoside triphosphate).

Finally, as in nucleic acids and indeed anywhere else (according to the official definition of the nucleotide), there is only one phosphate group allowed to attached to each nucleoside (regular phosphate group) to form a nucleotide (officially). Therefore there is no variation allowed in the phosphate groups (since there's only one and they bond to other nucleotides, in the same way, every time (in nucleic acids)), furthermore in the pentose sugar the only variation allowed is whether it is a ribose (in RNA) or a deoxyribose (in DNA). So the phosphate-sugar backbone of the DNA strands and the RNA strands (nucleic acids) are consistent throughout the entire strand (and each strand of its type; differentiating only in the type of pentose sugar it consists of (ribose/deoxyribose)). Consequently, there is no phosphate-sugar backbone variation within DNA strands or RNA strands, for the phosphate or the pentose sugar to make any genetic difference to genetic material (those strands); only the nitrogenous bases and their sequences can make a difference to the genetic material...

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