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1500 questions
25
votes
2 answers

Why do blood vessels in the eye not obstruct vision?

As light enters the eye, it reaches the photoreceptors at the "base" of the retina, which then pass that signal to the bipolar and ganglionic neurons -- the latter of which send the signal outside of the eye via their axons (collectively forming the…
theforestecologist
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2 answers

Can an adult without genetic lactase persistence still develop a tolerance for dairy foods?

While investigating the rise of adult lactose tolerance, I came across the news that China has been encouraging its citizens to drink more milk, even though most of the Asian population lacks the SNP (single-nucleotide polymorphism) which conveys…
Chris Wenham
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25
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2 answers

Are there life forms that freely fly in the atmosphere?

Are there (unicellular) Earth lifeforms that most of their life fly high in the atmosphere without contact with surface? For instance, in clouds, etc? If so, at what max altitude have they been detected?
Anixx
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What is the criticality of the ribosome binding site relative to the start codon in prokaryotic translation?

In prokaryotic translation, how critical for efficient translation is the location of the ribosome binding site, relative to the start codon? Ideally, it is supposed to be -7b away from the start. How about if it is -9 bases away or even more? Will…
Gergana Vandova
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24
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1 answer

What are the environmental conditions for SARS-CoV-2 to survive?

What do we know about the environmental limits for nCoV to survive outside the body? For example, in: In open air On surfaces In water What are the limits for temperature, humidity and air pressure, where the virus, can or cannot survive?
not2qubit
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24
votes
2 answers

Does sleeping fewer hours than needed cause common cold?

Does sleeping fewer hours than needed cause the common cold? If so, how?
rahul
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24
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2 answers

What exactly is this small puffer fish doing and how did it manage to accomplish such a feat?

I recently saw a video on youtube where it shows a puffer fish making intricate designs in the sand: OZZY MAN VIDEO The puffer fish made this design on the sand: What exactly is the puffer fish doing and how is it capable of accomplishing such…
user35897
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24
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1 answer

Why do dogs try to cover their poop?

It may seem obvious to us humans to hide our excreta, but this is not quite normal behavior for animals. Interestingly, dogs have the habit to pee all over the place. It's know that they do so to mark their territory. So when they want to mark their…
Steven Roose
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24
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9 answers

Why have humans evolved much more quickly than other animals?

Humans have, in a relatively short amount of time, evolved from apes on the African plains to upright brainiacs with nukes, computers, and space travel. Meanwhile, a lion is still a lion and a beetle is still a beetle. Is there a specific reason…
Matt Cashatt
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24
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5 answers

Are there any examples of sudden leaps in evolution?

As far as I understand, various abilities like flying, sight, hearing etc. were caused by slow evolution, where those with a greater ability to to these things had better chance of survival. (If this assumption is wrong, then I am happy to delete…
David
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24
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1 answer

Why does my room suddenly look 'reddish'? My eyes seem to adapt to color

To get the context of this question clear, I would like you to walk through some parts of my house. We'll start with one of my rooms as it appears normally - As evident, this part of my house has a creamish tinge to it, also the balcony door is…
Sarthak123
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24
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2 answers

Identification: Creepy 'nope'

While walking back from our routine evening stroll through the hills, we stumbled upon some insect(?). It was the size of an index finger, and it appeared to have some sort of wings. While I tried to take pictures of it, it started turning towards…
Poul Kruijt
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24
votes
1 answer

How did scientists discover HIV?

Imagining that we're now in 1983 (when HIV was discovered), there were no modern machines at that time to sequence massive genome extracted from blood. There was a strange disease and no one know what caused it, it's a virus or a bacteria or…
joe
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24
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3 answers

What is the name of this red plant?

I came across this plant yesterday (14th May) and was wondering what it might be? Would anybody know the scientific name and if it's indigenous to the UK (personally I doubt it is)? The plant grows in an Asian style garden near Cumnock,…
Johnny
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1 answer

How did the felines get to America?

I don't know if the felines got originated on America or on Africa, but I do know there are species of cat in America and Africa that belong to the same family and genus (Felidae & Panthera). How did the evolution of these animals beat the vastness…
Felipe Borges
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