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1500 questions
32
votes
4 answers
Do men have more extreme variations than women?
This question was considered unsuitable for Skeptics and I think it is more suited to BIology than Cognitive Sciences
I was reading this article which I found interesting. It is not supported with references but was an invited address for the…
Sonny Ordell
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32
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4 answers
What is the lowest pressure at which plants can survive?
What is the lowest pressure at which plants can survive? How the plants behave in a Martian-type atmosphere? Is there any plant that can survive such atmosphere?
Can a lichen grow at Martian pressure?
Anixx
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32
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1 answer
Are these microscopic star-like structures on a dead leaf some sort of organism? If so, which one?
I’m wondering what these star-shaped organisms are on a dead leaf I found in my backyard (Texas, USA). This was taken under my microscope at 40x magnification. They seem to be clear organisms with multiple outgoing “rays” that somehow benefit with…
Obama2020
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32
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3 answers
Why do mammalian red blood cells lack a nucleus?
How did the red blood cell in humans get to lose its nucleus (and other organelles)? Does the bone marrow just not put the nucleus in, or is it stripped out at some stage in the construction of the cell?
John Smith
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32
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4 answers
Why aren't there any competing biologies on Earth?
Why aren't there any competing biologies on Earth? I read sci-books about life based on silicon and I've read an article that said that other structures than DNA can encode genetic information.
So does physics allow for many competing biologies?…
Sayaman
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31
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3 answers
Can humans ever directly see a few photons at a time? Can a human see a single photon?
I am not asking the following question: Can humans ever see a photon in the same way we see a chair?
My question is: Can a human retina respond to a single photon? If so, how does this happen and why is the retina able to "sense" (detect) a single…
Daniel Mera
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31
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7 answers
How can homosexuality evolve despite natural selection?
I would imagine that the answer to this question would be population control, especially since even if one sibling is homosexual this does not necessarily mean that the other siblings will be too.
Josh Pinto
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31
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3 answers
Can plants suffer from CO2 poisoning?
Is there a point where too much CO2 is bad for a plant? Basically when there is too much CO2 in the air can a plant get sick?
Since plants photosynthesize and need CO2 to generate glucose and store starch, and since chemical reactions are pushed…
Lenkan
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31
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2 answers
Why is the Red Fox colored bright orange?
They're not poisonous or anything, so it can't be aposematism. As far as I know it doesn't come from diet like the flamingo. They're not apex predators, so they can't get away with it (like tigers), and honestly it seems like a big risk factor…
NML
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31
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1 answer
What strange jelly-like thing is shown in the photo?
What is shown in the pictures below? The photo was taken at the Australia's south coast (Queenscliff). The length of the thing is no longer than 50 cm... It doesn't move and has jelly-like consistency... My guesses were either some product (egg…
Capo Pavel Mestre
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31
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2 answers
Why do tattoos persist if body cells are regularly renewed?
I am not quite sure if it is true, but I read somewhere that within 7 years all the body's cells are replaced with new ones. I am not quite sure if it is cells or atoms.
If it is then why do tattoos persist for so long? If the cells which were…
vfclists
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31
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4 answers
Is "computational biology" different from "bioinformatics"?
Are "computational biology" and "bioinformatics" simply different terms for the same thing or is there a real difference?
Chirag
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31
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4 answers
Why do we need red blood cells?
From what I know, the main function of red blood cells (RBCs) is hemoglobin transport. So, why do we need cells packed with hemoglobin: why can't it travel freely in the bloodstream?
My own thoughts were:
1) Having hemoglobin packed into cells…
Eva
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31
votes
3 answers
Why can white hairs get dark again?
I have learned (probably in high school?) that hairs turning white is caused by the part of the folicle which produces the pigment dying and being replaced by an air bubble. This sounds very irreversible.
I have long dark brown hair, and since I…
rumtscho
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31
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6 answers
Why did abiogenesis only happen once?
If the "primordial soup" theory of abiogenesis is to be believed, self-reproducing organisms spontaneously arose on Earth at least 3.5 billion years ago, surprisingly soon after the Earth cooled down enough to potentially harbor life.
It may never…
manterr
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