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1500 questions
29
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3 answers
How, on a physical level, does ATP confer energy?
When ATP is used as the energy currency to make, say, reaction X + Y → Z happen, is what happens on a physical level down at the molecular scale that during the reaction
ATP + H2O → ADP + Pi ΔG˚ = −30.5 kJ/mol (−7.3 kcal/mol)
that 30.5 kJ/…
mring
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Earth overshoot day: is it a sound concept?
Today, August 8th, is Earth Overshoot Day (EOD) for 2016, the day when humanity supposedly has consumed the natural resources available from the planet for the year 2016; we're now running a deficit, somehow. At least if your believe the…
Roland
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29
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Is it possible that by mutation a human could see infrared or other 'colours'?
Incoming light reacts with the several types of cone cells in the eye. In humans, there are three types of cones sensitive to three different spectra, resulting in trichromatic color vision. Each individual cone contains pigments composed of opsin…
Marijn
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29
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3 answers
Can the dead be brought back to life by viruses?
Zombies have been a part of popular culture for decades. The living dead rising up to take over the world is a terrifying concept, worthy of Hollywood blockbusters and television hits. Some of those zombie fiction stories are based on infection by…
Sajin Shereef
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29
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Are there any substance that are more dangerous at low dose than at higher dose?
It is commonly admitted that
The dose makes the poison
which means as a person, the more I take a substance, the more risk I take for my health.
There is even an indicator called LD50 (see Median Lethal Dose), which specifies the 'lethal dose' at…
JBE
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29
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Smallest viable reproducing population
What is the smallest viable reproducing population, such as in a human population. By viable I mean a population which keeps genetic defects low (enough).
A very strongly related question: what is the expected number of generations a given…
John Smith
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29
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Is kissing a natural human activity?
The word natural here is meant in contrast to it being a sociological construct.
Is kissing in all its forms something natural for humans? Is it instinctively erotic? Or is it just a conventional form to show trust and intimicy, i.e. the…
Nikolaj-K
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29
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Where do migratory birds go when it rains?
I was reading a comic from XKCD which inspired me to ask this question: "well, where do they go when it rains?" I know that when it rains you usually don't see any birds flying through the sky.
I imagine they normally hide in trees or under other…
Pimgd
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29
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Why do we grow so much hair on our heads compared to our bodies?
I've been wondering about head hair, facial hair in particular. Human males can grow very extensive beards should they choose to not shave - however you do not really see this in our chimpanzee cousins! Yes, they have little pseudo-beards, but the…
Luke
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29
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Do trees age on a microscopic level?
Most animals age via at least two mechinisms:
at a "macroscopic" level, basically wear and tear to the point where (on evolutionary time scales) it's more genetically advantageous to optimize for reproduction rather than longer lifespans.
at a…
Shep
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29
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Is humans' height ideal?
More or less we humans are around 1.70 meters tall.
My question is, would it be possible to scale us? that is, is it in principle possible having humans 1 cm tall, or 10 meters tall or is there some reason that makes our height somehow ideal?
PhoenixPerson
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29
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Why is rabies incurable?
I'm still not sure about the mechanics that lead to rabies being incurable. I know that it can be treated before any symptoms show up, but why is it that once symptoms show the person is a dead man walking?
thomasrive
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4 answers
Can humans eat grass?
Can a human eat grass and digest it?
Could it be possible to use it as food just like other plants such as wheat or beans?
Xander Smeets
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29
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Natural examples of XOR functions at the cellular level
We can often think of cells as a sort of circuit on macromolecules, and can show that they can accurately and robustly implement functions like $\text{MAJ}(x_1,...,x_n)$ (return $1$ if more than half of $x_1,...,x_n$ is $1$ and $0$ otherwise) under…
Artem Kaznatcheev
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29
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Why do wasps have "wasp waists"? What's been optimized?
I photographed these (unidentified) wasps on a sunny but cool winter day in northern Taiwan because they were conspicuously hanging out on a hand railing and had much lighter coloring than I'd ever seen before.
But after I took the time to look at a…
uhoh
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