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1500 questions
33
votes
4 answers
How do trees manage to grow equally in all directions?
I was walking down a road with these beautifully huge trees when this question occurred to me.
Large trees with many thick branches have to grow equally in all directions, or they would tip over. Is there some sort of mechanism to ensure this…
Amu
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32
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1 answer
Are drugs made bitter artificially to prevent being mistaken for candy?
All drugs I remember tasting (with the notable exception of Aspirin) have bitter taste. Is the taste due to the active substance, or is a bittering agent added to them, perhaps to prevent overdose?
Take Paracetamol for instance: adult pills taste…
Dmitry Grigoryev
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32
votes
4 answers
How does cerebrospinal fluid circulate in the central nervous system?
Cerebrospinal fluid (CSF) is produced in the choroid plexus of the lateral ventricles and in the 4th ventricle of the brain. CSF then circulates through the ventricles of the brain and the subarachnoid space of the meninges. CSF is returned to the…
DQdlM
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32
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3 answers
Can you be immune to a coronavirus?
Can one be immune to the new coronavirus?
Another question is what is the exact definition of "being immune". Does it mean that even when the virus enters my system, it cannot multiply?
kokoo
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32
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3 answers
Why is saltatory conduction in myelinated axons faster than continuous conduction in unmyelinated axons?
How does spacing apart sodium and potassium channels allow the action potential to travel faster down the axon? This is the reason always cited for saltatory conduction and myelination, but my mental model of conduction tells me that the density of…
user7924
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32
votes
1 answer
What is this bizarre looking animal we found in the forest? Bug identification
Please can someone identify this?
I can't find anything on the Internet like it. 2 cm long. North Bohemian mountains (Czech Republic).
Sentinel
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32
votes
6 answers
Biological siblings possible with <9 months age difference?
I'm currently in the middle of writing a story, and one of the story elements threw up a question for me. In this story, there are two siblings, who are only one or two months apart in age. As they grow older, they start to question how this age…
user35717
32
votes
1 answer
How could a species be engineered to go extinct?
Non-biology background here.
I read this very interesting article: https://www.wired.com/story/crispr-eradicate-invasive-species/
However I am having a hard time wrapping my head around something:
From my basic understanding of natural selection, a…
Nathan H
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32
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2 answers
What makes a cancer contagious?
Most human cancers are not (very?) contagious (perhaps besides a couple of incidents). But the Tasmanian devil seems to have a form of cancer which is contagious. Now what makes the difference between a contagious cancer and a non contagious cancer…
Marijn
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32
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4 answers
Why is DNA replication performed in the 5' to 3' direction?
DNA replication goes in the 5' to 3' direction because DNA polymerase acts on the 3'-OH of the existing strand for adding free nucleotides. Is there any biochemical reason why all organisms evolved to go from 5' to 3'?
Are there any…
Damian Kao
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32
votes
7 answers
Is evolution a fact?
Richard Dawkins in one of his videos says that Evolution is a fact and not just a theory.
He goes on to say that man and chimpanzees both evolve from apes.
Is this correct (Is evolution a fact and did humans & chimps evolve from apes)?
Farhan stands with Palestine
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32
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2 answers
How do we know the human species arose in Africa?
I have heard (from multiple sources) that the current scientific opinion is that the human species arose in Africa. What are the reasons for this opinion? If possible, simple and non-technical explanations (as far as possible) would be appreciated.
Faheem Mitha
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32
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1 answer
How did viruses come to be?
My question is out of curiosity and got me thinking. How did viruses with the head, tail and tail fibres actually evolve? These viruses look more like machines than biological entities. Are there any theories to how these viruses evolved?
harpalss
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32
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4 answers
Were there any flying dinosaurs?
I've seen some articles which came in contradiction with each other.
The first article was talking about flying dinosaurs, dinosaurs with feathers and so on.
A couple of other articles are talking about misconceptions about dinosaurs one of them…
Rotari Radu
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32
votes
4 answers
Books on population or evolutionary genetics?
I have recently been involved in collaborations that require me to model the population genetics of eukaryotic populations. I fear I may either be "re-inventing the wheel" or making conceptual mistakes (e.g. simplifying assumptions) in many of the…
hello_there_andy
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