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7h
comment What is this caterpillar?
This question is pointless without an image. Please post on imgur and add a link to your question.
7h
answered Are mitochondria dead?
14h
comment What is the name of this flower?
Please indicate where this is located.
17h
comment What happens when a genome is shorter than the other?
@TheLastWord a second or third species was never mentioned. OP talks about Creatures 1, 2, and 3, but they are all the same species. The question seems pretty clear to me - What happens when homologous sequences of DNA have short insertions or deletions on one chromosome but not the other?
1d
comment How does a smoker's finger or mustache get yellowish by nicotine?
(...) Additionally, a question should be just that - a single question. Asking multiple different things in the same question makes it more broad, and makes it less likely that a single, concise answer can address all of the points.
1d
comment How does a smoker's finger or mustache get yellowish by nicotine?
This is general practice for all Stack Exchange sites, and is referred to as "moving the goalposts." Yes, of course questions may be edited to be clarified, or to add new information requested in comments, etc. However, it is bad form to add new, only tangentially-related questions to the original question, especially after answers have been submitted. Those answers may be downvoted later by users who see the expanded question, and an answer that apparently only addresses part of it. (...)
1d
revised Driving force for speciation for millions of species today
edited title
1d
comment How does a smoker's finger or mustache get yellowish by nicotine?
(...) Drugs.com indicates that the nicotine is sandwiched between 2 polyester backings and embedded in a matrix of various polymers, so $O_2$ likely can't interact with it.
1d
comment How does a smoker's finger or mustache get yellowish by nicotine?
@AliceD see my comment on the other answer regarding the color of nicotine. I checked out a bunch of different chemical resources and vendors, and most seem to indicate that it is generally in the yellow-brown spectrum, as it is most commonly exposed to air (such as in a cigarette). I think it's only clear when freshly prepared and/or maintained in an oxidation-resistant environment, which would be the case in pharmaceutical manufacturing for nicotine replacement therapy patches. (...)
1d
comment How does a smoker's finger or mustache get yellowish by nicotine?
Please do not change the question significantly, especially after answers have been submitted. Instead, ask a new question.
2d
comment Microwave and Health
Short answers: 1) No, 2) none, unless you stick your head in it, and 3) no. Generally, though, microwaves only act by heating small polar molecules like water, which then heat their surrounding molecular neighbors.
2d
comment How does a smoker's finger or mustache get yellowish by nicotine?
BTW, I think you meant perspicuous. At any rate, I wouldn't use it here (maybe on English Language & Usage) as not many native English speakers know what it means, let alone those for whom English is a non-native language.
2d
comment How does a smoker's finger or mustache get yellowish by nicotine?
Nicotine is generally yellow to dark brown. While the pure chemical may be colorless, it oxidizes upon exposure to air, changing its color to brown. I added a "citation needed" template to the section of the wiki page you linked, as far more sources I checked said something along the yellow-brown spectrum than colorless.
2d
comment How does a smoker's finger or mustache get yellowish by nicotine?
Parsimonious does not mean what you think it means.
2d
revised Do any amphibians start their lives on land?
deleted 5 characters in body
Jul
25
comment Do the enzymes and compounds in saliva help with stain removal?
Why spit when you could just use soap and water?
Jul
25
comment People who are very “aware” or very sensitive, is the brain more advanced or less advanced?
I'm voting to close this question as off-topic because it is much better suited to Cognitive Sciences.
Jul
25
revised People who are very “aware” or very sensitive, is the brain more advanced or less advanced?
added 3 characters in body
Jul
25
comment Why do Shiitake mushrooms grow on logs?
@TomD Not really. There is a perfectly logical biochemical explanation for why the avidin-biotin bond is so strong. As for the presence of avidin in eggs and Streptomyces, the exact reason is not known, but there are reasonable hypotheses. As far as the OP's question, though, there is no reasonable hypothesis of which I'm aware that explains why shiitakes grow on decaying trees, except the generic evolutionary explanation that it was an ecological niche that could be filled, so it did.
Jul
25
comment How long does conception take?
There is research showing that spermatozoa contain a number of RNA species, including mRNA, so theoretically translation could begin almost immediately. The Wikipedia articles on human fertilization and fertilization in general contain lots of other information, if you haven't read them already. Unfortunately, there's nothing in them about timing that I could find. I'm sure it's out there, though.