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1500 questions
42
votes
5 answers
Why did life not evolve to use radio?
We use electromagnetic communication everywhere these days. Cell phones, wifi, old-school radio transmissions, television, deep space communication, etc.
I'm curious about some of the possible reasons we have never seen biological systems having…
Geuis
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42
votes
1 answer
Why do ants live so long?
I was surprised to learn that worker ants in some species live many years. I would have expected a lifespan of a few weeks or months (which is apparently the case for many species).
What factors might account for the length (and/or variation) in…
yep
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42
votes
6 answers
Do humans have enough biological differences to be grouped into races or subspecies?
After my online research on the subject, I learnt that, biologically speaking, many scientists believe that there is no such thing as a race. Homo sapiens as a species is only 200,000 years old, which has not allowed for any significant genetic…
Th334
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41
votes
3 answers
How does a Coronavirus "test kit" work?
A number of countries are using test kits for detecting new cases of nCoV (2019-Coronavirus) and apparently China is running low.
What exactly is in a nCoV "Test Kit" — How does it work?
(Surely they also differ, so in which way do they differ?)
not2qubit
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41
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5 answers
Why Is Most Life Symmetrical Externally But Not Internally?
Mammals, reptiles, arachnids, insects, etc are all as far as I am aware symmetrical in appearance.
Take a human for instance, make a line from the top of our head right down the middle. However, internally it is not the same. Our organs excluding…
kittycat
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41
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5 answers
What does the human body use oxygen for besides the final electron acceptor in the electron transport chain?
My biology teachers never explained why animals need to breathe oxygen, just that we organisms die if we don't get oxygen for too long. Maybe one of them happened to mention that its used to make ATP. Now in my AP Biology class we finally learned…
Gordon Gustafson
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40
votes
4 answers
Can a person survive on blood in place of water?
This question: Can you get enough water by eating only fish? asks if a person could survive on fish alone. Can a person survive on fish and/ or blood alone of any species if stuck at sea or animal blood as a last resort where there is no water or…
Muze
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40
votes
2 answers
Why are prions in animal diets not destroyed by the digestive system?
According to CBC:
Mad cow disease is the common name for a condition known technically as bovine spongiform encephalopathy, or BSE. [...] The only known source of mad cow disease is from animal-based feed contaminated with tissue from a diseased…
Dare to ask-I dnt mind punishm
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40
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4 answers
Are there biological reasons why life expectancy is lower for men in most countries of the world?
I've been checking life expectancy figures for men versus women in many countries of the world and the figures for men sometimes are terrifying. Countries like Russia have a 12 years gap in disfavor of men. Developed countries have usually a 4-5…
Pablo
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40
votes
2 answers
Why do some vegetables taste bitter?
Bitter gourd, cucumber, etc. are bitter to taste. Which chemical causes bitterness in them?
I found these when I searched online: this says that it is because of calcium, while this and this talk about physical effects.
Mesentery
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40
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4 answers
Can humans perceive sounds above 20 kHz?
In the never-ending debate raging in the audiophile community about sound quality and what humans can or cannot hear, it is very very very very incredibly often cited that the upper-limit of the audible range of human hearing is 20 kHz, give or…
landroni
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40
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2 answers
What actually happens when my leg 'falls asleep'?
Most people have experienced the temporary loss of feeling and tingling in their leg resulting from sitting in an abnormal position for a short while. Usually you get a loss of feeling in your leg while it is being compressed/constricted at some…
Gordon Gustafson
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39
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5 answers
Can bacteria be killed by purely physical trauma?
In a question over on Skeptics Stack Exchange, I half-jokingly listed "blunt force trauma" as a means by which a bacterium could be killed. That makes me wonder if it really is only a joke or whether such an assault is plausible. The webcomic xkcd…
Robert Columbia
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39
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5 answers
Virus cannot survive on surface after certain time period, but why and how?
I'm not a biology student at all, but I'm trying to get a clearer picture on what is meant by "virus cannot survive after a certain period".
To my understanding, a virus cannot be killed it can only be inactivated (for example, by means of heat and…
Zarick Lau
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39
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1 answer
Does it make sense to classify all humans in a single species?
For what biological reasons do we consider that all human beings belong to the same species?
A Thai and a Nigerian share a common ancestor that is 140,000 years old (see Gravel et al. 2010 and this post). Would, for example, a mixed Thai - Nigerian…
Remi.b
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