Wikipedia:Reference desk/Archives/Science/2015 November 17

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November 17

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Neuroscience: Is my "Sympathetic fight response" axis accurate?

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Peripheral sensory cell > Preganglionic cell > Dorsal root ganglia cell in the Sympathetic chain > Ventral root ganglia cell in the sympathetic chain > Post-ganglionic cell that activates an organ such as the pancreas (or a muscle).

Was I accurate? I ask this after feeling that some books\people tend to confuse the details of this axis... :|

Thanks, Ben-Yeudith (talk) 03:30, 17 November 2015 (UTC)[reply]

That pathway might come into play, but it wouldn't generally be called a "fight" response unless brain circuitry is involved. See fight-or-flight response, and for further information sympathetic nervous system and norepinephrine. Looie496 (talk) 14:31, 17 November 2015 (UTC)[reply]

Dehydration and swelling

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Why does dehydration cause swelling of various body parts? 2A02:C7D:B8FF:7E00:A9FD:A524:5C8A:311F (talk) 09:06, 17 November 2015 (UTC)[reply]

I don't see anything in Dehydration that talks about swelling. ←Baseball Bugs What's up, Doc? carrots11:14, 17 November 2015 (UTC)[reply]
Perhaps the questioner is thinking of the abdominal swelling seen in severely malnourished children. See here for some explanations. AndrewWTaylor (talk) 11:37, 17 November 2015 (UTC)[reply]
Kwashiorkor isn't a dehydration symptom (it's the product of a specific kind of malnutrition), but might be what the OP is thinking of. See also Swelling (medical) and edema. 99.235.223.170 (talk) 01:43, 19 November 2015 (UTC)[reply]

Gorse brush prickles cause a rash but what is the active agent?

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What about gorse bush prickles causes an inflammatory response? Getting prickled by gorse bushes causes an inflammatory response so the pricks appear as red spots which persist a couple of days following exposure. A friend said it was "phenolic compounds" but I can't find anything about it online. --129.215.47.59 (talk) 11:34, 17 November 2015 (UTC)[reply]

This [1] says that formic acid is present. SemanticMantis (talk) 15:20, 17 November 2015 (UTC)[reply]
Thanks but I think you misread the source. The formic acid is in nettles. --92.6.114.248 (talk) 20:54, 17 November 2015 (UTC)[reply]
The source provided says (quoting directly)
  • 78. Ulex europaeus
  • Common names:- Gorse
  • Part used:- flowers
  • Effects:- some astringent action, flea repellant
  • Chemicals present:- tannins. No further data available at the present time.
Relevant here is the statement that it has astringent properties which are likely caused by tannins. --Jayron32 21:20, 17 November 2015 (UTC)[reply]
@92.6.114.248: related event, this was caused by an 'inflammatory response' other then the gorse itself:
• "Dog walker killed by a scratch from a gorse bush" Daily Mail, May 2006.
The 74-year-old woman actually "... died from the 'flesh-eating bug' necrotising fasciitis" caused by "group A streptococcal infection". 220 of Borg 22:47, 18 November 2015 (UTC)[reply]
Yes, the Daily Mail headline suffers from the post hoc ergo propter hoc fallacy: She was killed after the scratch, by something unrelated to the nature of the cause of the scratch. --Jayron32 23:42, 18 November 2015 (UTC)[reply]
Like "We all eat food, and drink water and we all die", therefore: "Don't eat, or drink water, and you will never die"?  No, I think that's Correlation does not imply causation. - 220 of Borg 06:02, 19 November 2015 (UTC)[reply]