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1500 questions
17
votes
8 answers
Why don't we breathe nitrogen when it makes up most of the air?
Why don't we breathe nitrogen while it makes most of the air?
Why do we always tend to breathe oxygen, not hydrogen and nitrogen?
user4147
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17
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Quantum mechanics in biology
There is a growing interest in the applications of non-equilibrium quantum dynamics to describe biological processes (I'm not talking here about Penrose's old theories, but new stuff -- quantum coherence in light harvesting, magnetoreception etc.).…
quant_dev
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17
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3 answers
Why is there a difference in the rotation of the tail fin in fish compared to marine mammals?
I've been thinking about this one, but I can't seem to find what causes this difference.
All fishes that I've seen have their tail fin positioned vertical:
But all the marine mammals I know have their tail positioned horizontal:
Why is there this…
Simon Verbeke
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17
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2 answers
What effect does vortexing have on a fluid sample that simple mechanical shaking does not?
Some protocols call for fluid samples to be mixed with a "vortexer" on the high setting. What effect does the vortexing have on fluid samples that mechanical shaking does not? Does it shear long molecules like DNA, for instance?
A friend is…
Mac Cowell
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17
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1 answer
Do we actually get more sick (flu/cold) during winter?
The word flu derives from the Italian phrase "influenza de freddo" meaning "influence of the cold".
Indeed it is that time of the year when my colleagues seem to have the flu/cold more often than not. I remember during university, winter lectures…
hello_there_andy
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17
votes
1 answer
How does herpes (HSV) infection suppress HIV?
HIV compromises the human body to defend against infection. Yet people who are infected with herpes are at less risk of developing AIDS.
How does this work?
This question comes from this paper, which is hard for me to follow since I am uneducated on…
Gabriel Fair
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17
votes
2 answers
A weird-looking fish with a shield
I found this photo in a local news page. The page claims that this fish is a new species that was found by a Malaysian fisherman. Is this true or is it a known fish and already has a name?
user3130
17
votes
4 answers
Why do restriction enzymes tend to have an even number of bases in their recognition site?
When reading my textbook I noticed that in all examples but one from eight the recognition site was an even number of bases.
I wondered if this was just a co-incidence, so I took the data from this site for over a thousand known recognition sites…
Rory M
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17
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1 answer
Is it true that all spiders are venomous?
This is a factoid I heard as a kid at some point, probably on a playground somewhere, and just accepted without question in the way that children do:
All spiders are venomous, but most of them aren't venomous enough to harm humans.
(I'm pretty…
Hearth
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17
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4 answers
Can any other animal choke on food?
I read somewhere (I think it was Bill Bryson's book on the origins of the English language) that of all animals, we are the only ones that can choke on food (having something to do with how our larynx is positioned). I'm unable to find reference to…
Yevgeny Simkin
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17
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1 answer
Why haven't we cured the common cold yet?
Researchers think they’re close to a cure for the common cold, but they first need to solve a complex problem that’s perplexed scientists for decades. Polio, smallpox, hepatitis A and B are all serious viruses humanity learned to subdue with…
DARYL JOSEPH.G
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17
votes
1 answer
how to close a severed artery/vein?
This is a medicine-related question that I've been wondering about. I've been watching medical lectures on YouTube regarding the human body and was wondering about how surgeons treat a severed artery or vein (think Juggular or Carotid)? Specifically…
mj_
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17
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1 answer
What's this stuff that looks like white chainmail armor growing on giant kelp?
I found some giant kelp coated with a material that is white, smooth, and forms a chain-mail pattern with small black oblong lumps in between the links. It feels pretty hard but not stiff (the kelp still flexes), and can't be easily removed from the…
Robert
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17
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4 answers
Can two humans with 44 chromosomes produce viable offspring?
It is known that there are very few individuals having 44 chromosomes, not the usual 46 chromosomes.
One example is a male in China: the first article, the second article.
The other is a female in Turkey, unfortunately the article is in Turkish.
It…
Özgür
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17
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2 answers
How to decipher references in natural history works of the late Renaissance and early Modernity?
Old botany books from the 17th, 18th and 19th centuries (and maybe also some later ones) enumerating lists of species used to give references to their sources as abbreviations consisting of one or few truncated words and sometime numbers.
For…
botaflo
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