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1500 questions
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What is the human energy consumption by organ?
The human brain uses about 25% of the human body's metabolic energy. How are the other 75% spent, in terms of portioning to its various systems?
I thought this could be answered by a simple search, but I can't find the answer after searching very…
MaudPieTheRocktorate
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Does animal blood, esp. human, really have similar salinity as ocean water, and does that prove anything about evolution?
It is an often-repeated claim that human, and in fact all animal blood is salty because we evolved from aquatic organisms, and that blood has a similar concentration of salts as ocean water, or at least as primordial ocean water.
Is any of that…
Hackworth
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Can a cancerous cell from outside cause cancer in a healthy person?
If a cancerous cell enters the body of a healthy person from someone else's blood or something, will that healthy person get cancer? In human beings.
Poin
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Can one see flickering of a light bulb at 50 Hz?
Yesterday I had a BBQ with some friends. The sun had already set and the only light source left (besides some ambient light from the world around) was a low energy light bulb.
After a while I started to see lighting changes in the faces of my…
Timo
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What are the trajectories of flying insects?
Many flying insects tend to have very jagged trajectories. For moves of a fruit fly looks like a random walk.
Is there any research on the properties of trajectories (e.g. their fractal dimension or mathematical models producing similar…
Piotr Migdal
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Has there been any observation of species adapting the evolution process?
I am very interested in the evolution of the evolution process itself. There are of course a lot of things that influence how evolution will work, but for this question, I am interested in things that are only related to the evolution process.…
David
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Why does an electrical shock freeze up muscles?
Why is it when someone comes into contact with an electrical supply that their body freezes up and is unable to move away from the electrical source?
Can someone explain this through a physiological perspective?
Fraïssé
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Human evolution: Where *exactly* did the first human come from, whose parents were not?
Layman here. So I have never really quite understood this facet of human evolution, (or any other for that matter), in that, I understand the evolutionary process, but I get lost on the 'border' cases.
For example, we, as humans, evolved from…
Spacey
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Can rats pass on memories of a maze to their offspring?
A friend of mine told me once about a documentary movie he saw some years ago. On this movie he saw scientists talking about particular experiment. This experiment involved rats and probably electrical traps. The rat had to get to the cheese, there…
Osjan
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Is telomere length a reliable measure of health/lifespan?
Several companies are commercializing tests for telomere length such as this one here. I understand the basic mechanism for why telomeres shorten during DNA replication, but how good is the evidence that telomere length is a reliable indicator of…
Poshpaws
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What does vaccine efficacy mean?
In the last few weeks, Pfizer/BionTech, Moderna and AstraZeneca have each released preliminary estimates of the efficacy of their SARS-COV-2 vaccines.
But what do their respective efficacy percentages actually mean? Is the Pfizer/BioNTech vaccine…
thegreatwhatsit
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Do viruses or bacteria have a flavour?
My 9 year old niece asked me this when I was explaining some stuff to her about the coronavirus. She asked "What does this virus taste like? Can I tell whether my sandwich is contaminated for example?"
That sounded like a silly question and I…
polfosol ఠ_ఠ
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Does the genetic sequence of SARS-CoV-2 end with 33 A's?
Looking at the DNA (or RNA?) sequence of the Covid-19 virus here: https://www.ncbi.nlm.nih.gov/nuccore/MN908947.3
I notice it ends in 33 a's. Does the virus really look like that, or is it some artifact of the sequencing process, or some sort of…
Grumdrig
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If a human takes antibiotics are all bacteria in the body killed?
From my basic understanding, antibiotics kill living things, bacteria for example.
Do the antibiotics consumed by a human-being distinguish between what they kill? Or do they just kill every bacteria they find? And if that's the case, which bacteria…
Claus
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How long before robin no longer needs the nest on my porch?
A robin has made a nest on my porch. Unfortunately, the nest is on my weed wacker which I might want to use at some point this summer. Currently, there are two eggs in the nest.
How long will it be before the robin is done needing the nest?…
Imprisoned Rhesus
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