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September 10

DNA directionality

Hello,

I couldn't understand from the above article whether or not the definition of one strand as "5->3" and its opposite strand as "3->5" is arbitrary. Given a DNA helix where one strand A is called "5->3" and the other strand B called "3->5", can you turn over the DNA helix and then A would be "3->5" and B would be "5->3"? Thanks, 212.179.21.194 (talk) 07:50, 10 September 2015 (UTC)[reply]

The two strands in the double helix are identified as sense and antisense depending on how the RNA decodes them. You can read that article to indicate how the two strands are identified. The "5' sense" end and the "3' sense end" would not be interchangeable, and can be used to absolutely orient the DNA double helix and avoid the problem you note. --Jayron 32 09:54, 10 September 2015 (UTC)[reply]

Note that sense and antisense are dependent on which gene you're talking about. It's perfectly possible (and does occasionally happen) that there are some regions of DNA where one gene is read from one strand, and another gene partially overlaps it but is read from the other direction. In this case, the "antisense" strand of one gene is the "sense" strand of the other gene. The DNA helix is symmetric, and any directionality of the double helix is context dependent. So which strand is the "5'->3'" one and which is the "3-'->5'" one does depend on which end of the double helix you label as "start" and which you label as "end", and that decision is somewhat arbitrary, depending on what context you're talking about things. -- 160.129.138.186 (talk) 15:03, 10 September 2015 (UTC)[reply]

I've tried to make that article's first few paragraphs a bit clearer ... not sure if I achieved this. These articles are tough because you want to explain so much in so many directions and you never know what you're failing to communicate, but it's worth doing more of. Wnt (talk) 15:21, 11 September 2015 (UTC)[reply]

Is there some animal other than homo * species that make music?

Is there some animal other than homo sapiens (or our extinct ancestrals) that make music?
PS: I am really talking about animals doing music, I am not talking about animals just doing sounds that were them called music by humans, (to better explain some similar problem or situation that happens, are hyena vocalizations that humans call "laughts" but are just non laught vocalizaton)201.78.128.120 (talk) 12:45, 10 September 2015 (UTC)[reply]

Sure, most people consider birdsong to be music. That's a very complicated thing. Some of birds mostly sing a few songs, and they are fairly instinctual/innate (e.g. a solitary raised bird will sing pretty much the same songs the parents did, even without learning). Other birds pickup and "create" all kinds of different songs, like the Lyre bird or mocking bird. Birdsong is a very active area of research, you'll find lots of neurobio and behavior bio stuff on google scholar, like this [1].

Also lots of stuff about music in chimpanzees - mostly drumming. See here [2] [3] for recent news articles and audio clip, here [4] [5] [6] [7] for some scholarly sources. SemanticMantis (talk) 13:13, 10 September 2015 (UTC)[reply]

Also Whale song - it seems they "compose" lots of different songs, but I don't know much about that, so see refs therein for further info. SemanticMantis (talk) 13:22, 10 September 2015 (UTC)[reply]

"it seems they "compose" lots of different songs, " Thats is exactly what I was not asking for, they must make music and not "make music" in the same way as hyenna "laughts". — Preceding unsigned comment added by 201.78.128.120 (talk) 16:41, 10 September 2015 (UTC)[reply]

Maybe you need to define your terms more strictly. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:54, 10 September 2015 (UTC)[reply]

No, whale song is very different from a hyena laugh. You don't have to think of it as music, but many people do. They produce a series of notes with different pitches and duration, and make different songs at different times, and also make novel utterances. It is true that their vocalizations are also communcative. Then again, so is much of our music. SemanticMantis (talk) 17:19, 10 September 2015 (UTC)[reply]

With hyena laught I was talking about the fact people say hyena laught, when in fact the "hyena laught" is not really the hyena doing the act of laught (as some site said, what they are exactly doing is that they are signaling to others they want to be left alone). This is to explain that I am asking if animals can decide to produce music (and then do it), and not if its possible to animals produce sounds while runing out with their lifes, that us as humans would think as music the answer to this one would be obviously a yes since the thing called birdsong is ultra common and famous.152.236.248.218 (talk) 00:21, 11 September 2015 (UTC)[reply]

Question to the OP: do you only want to discuss music made using instruments, that is items that are not part of the animals' body? --Lgriot (talk) 17:59, 10 September 2015 (UTC)[reply]

Somebody was playing these magical mammoth and vulture flutes back in the not-quite-homogenized day. InedibleHulk (talk) 19:18, 10 September 2015 (UTC)[reply]

And there's the Fraggle Horn, but that obviously doesn't count, because it's monotonous. InedibleHulk (talk) 19:30, 10 September 2015 (UTC) [reply]