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1500 questions
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Does current evidence support the use of resveratrol as an anti-ageing drug?
A while back there was a lot of noise about resveratrol, a naturally occurring phenol which was touted as a potential anti-aging drug due to its role in regulating the SIRT 1 gene. A number of studies suggested that it could extend the lifespans of…
Poshpaws
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Can forensic DNA analysis be used to generate a visual approximation of a suspect?
In light of the current US supreme court case, I'm curious if enough information can be teased out of a DNA sample to get a "reasonable" approximation of the suspect (never mind the legality). I realize the term reasonable is subjective, so…
single_digit
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Do fallen leaves produce oxygen?
After a leaf has fallen from a tree, if it is still green and hasn't dried out, is it still converting CO2 into O2 if not put in water?
Can anyone find any data showing how long any different species of leaf will continue to produce oxygen after…
Johan88
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How do we sweat immediately after drinking water on a hot day?
On hot summer days, when I drink water to quench my thirst, my body immediately responds by sweating in 5 to 10 seconds or maybe less. How does our body detect the presence of water in the stomach so fast. Does our body detect the sudden decrease in…
Kevin Selva Prasanna
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What is this thing that is growing in my yard? And should I get rid ot if?
I live in Wilmington, Delaware (Mid-Atlantic USA). The north side of my yard is largely shaded by my house and grass is spotty.
Periodically when I go into the yard I will find as many as four pod-like things have opened on the ground. I almost…
Wildcat Matt
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Was iron important for the first life on Earth?
Some ions or compounds are thought not to have become involved or important in the metabolism of living organisms until some time after certain mutations took place. For instance, early life is thought to selectively allow calcium ions through its…
John Joe
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How does DNA still work after recombination?
If you take two computer programs and randomly swapped pieces from each of them. The result is not going to work. It will just be garbage. If you take two novels and randomly swapped chapters the result will be garbage too.
How is it than DNA…
zooby
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Inexperienced divers damage coral, but parrot fish eating coral doesn't do damage?
I've been learning about life on coral reefs. Recently I've become aware of the damage to coral reefs caused by tourism and inexperienced divers:
1) Corals have a thin membrane which keeps them healthy. Touching them could break this membrane,…
Kiyocean
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Which sex has higher variance of reproductive rate in modern societies - male or females?
Who has a more varied reproduction rate in modern western societies - men or women? The average rate is the same of course, but I wonder which sex have higher variance - higher variance means that reproduction is more concentrated in some subgroup…
Qbik
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Can someone identify this Brazilian bird?
Photographing and documenting the local fauna (Brasília, DF, Brazil - Near Coordinates [-15.696506 -47.860013]), I found this rather unusual-looking bird whose name I couldn't find:
(Image was now uploaded to Wikimedia under my account…
A random foreigner
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2 answers
Can a shark stall?
Today in marine biology I learned that, like airplanes, sharks use their pectoral fins to generate lift. The question that neither me or my Professor know is if a shark can or cannot stall.
A stall occurs when the angle of attack of the wing (in…
Donovan Cunningham
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3 answers
Human genetic diversity in Africa in comparison with the rest of the world
Background
The claim ...
Most of the genetic diversity in humans is in Africa
... is quite common. On Biology.SE, it is easy to find posts that make this claim. Consider for example:
Do humans have enough biological differences to be grouped into…
Remi.b
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What predates on cactus in the Atacama desert?
Introduction
Last week, I was in the Atacama desert where I've seen many cacti. Some / many of them were seemingly suffering from predation. Most of predation seemed to be on cardón, often restricted (but not only) at the interface between the woody…
Remi.b
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Why doesn't ovulation occur in both ovaries simultaneously?
I know that in human body ovulation takes place at only 1 ovary every month. But development of a follicle depends on FSH levels in the blood, and since both the ovaries are exposed to the same blood supply, how does it make sense for development of…
Adithya Eshwarla
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3 answers
Do humans produce rennin?
At school, we've been taught that human infants produce rennin/chymosin (which aids in the digestion of milk). More specifically, it is the peptic cells in the stomach which secrete prorennin, the inactive form of rennin (in addition to pepsinogen,…
paracetamol
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