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1500 questions
27
votes
7 answers
Why are there exactly four nucleobases in DNA?
Does someone know why DNA is composed of four nucleobases? In particular, is there an explanation for the number? Why four and not two, or eight?
tunnuz
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27
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3 answers
Why was disease transfer to the Americas one-way?
It is well known that the European colonists brought many infectious diseases to the Americas, and that these had a deadly effect on the native populations, because they had no immunity to them. Were there any local infectious diseases to which the…
TRiG
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27
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2 answers
How do biological communities at deep-ocean hydrothermal vents migrate between vents?
Much interest in the astrobiology community has been generated by the discovery of biological communities populating deep-ocean hydrothermal vents (i.e. "black smokers"). (1) These ecosystems rely on chemoautotrophic bacteria/archaea extremophiles…
Poshpaws
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27
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3 answers
Did predators evolve eyes first?
I'm an engineer and biology is my weakest point, so please forgive if this question is dumb.
Lately I've been wondering, "Why do animals that have eyes tend to have exactly 2 of them?" The closest related answer I can find is that 2 eyes provide…
James Strieter
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27
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2 answers
Why don't viruses reach broad concentration outdoors in a city like allergens?
Why don't airborne viruses reach concentrations that infect most people vulnerable outdoors in a city the way an allergen can cause inflammation to everyone sensitive to it. Both are (often) microscopic airborne biological particles produced by a…
davolfman
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27
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5 answers
Why did scientists state that the Omicron COVID-19 variant was a reason to get a booster?
I was watching Vox’s video, Big questions about the Covid booster shot, answered, which references the New York Times article Omicron Prompts Swift Reconsideration of Boosters Among Scientists.
In these sources, it is mentioned that the scientific…
hb20007
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27
votes
2 answers
What is this spider with blue striped head?
I found this spider on the balcony of a Brisbane, Australia quarantine hotel. About 1.5cm. Anyone know what it is?
Kels
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26
votes
1 answer
Are human chromosomes connected or separate molecules?
Do the 46 human chromosomes form a single unbroken DNA helix? Or is it rather that a human's genome consists of 46 disconnected helices?
If it is the former, does the common numbering scheme for the chromosomes have any correlation to their…
lilinjn
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26
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1 answer
Specific mechanism behind lethality of yellow coat color in mice
Our high school genetics chapter has some extra information about L.Cuenot. It only covered his research, and the fact that mice homozygous for yellow coat color would die before birth. It was an example of a lethal allele.
We have learned about…
Amarylis Vaselaar
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26
votes
1 answer
Why is untreated trypanosomiasis invariably fatal in humans?
If left untreated, African trypanosomiasis will invariably kill the patient. The human immune system is unable to clear the infection.
I am aware of a few other infectious diseases with this property and I have a rudimentary understanding of the…
Brian
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26
votes
4 answers
Do immortal organisms exist?
Do organisms exist that are able to live indefinitely if they are not killed by external factors?
Under external factors I would consider things like predators and natural disaster but not illness by bacteria for example.
Steven Roose
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5 answers
Examples of plant families that contain species that are safe for human consumption and species that are poisonous to humans?
I am trying to make a point to someone that just because two plants share a family and one plant is safe for human consumption, it does not follow that the other plant also is safe for human consumption. Can anyone provide an example I can use as…
Im_no_botanist
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26
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3 answers
Do oysters feel pain?
Do oysters feel pain when you bite into the inside, or when you crack open the shell? I tried google searching it to no avail. When you bite inside the oyster or when you break the shell to open the oyster, does it feel pain?
EDIT: (Since some…
Sweet_Cherry
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26
votes
3 answers
Why is the Hydra Biologically Immortal?
I have heard that the Hydra organism is biologically immortal (later I found that there are more immortal organisms). Now I know that its immortality is related to its telomerase. The thing is that we all have telomerase, but we age and Hydra don't.…
MySky
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26
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1 answer
Bird brain-eating Mantis - how does it crack the skull?
The New York Times' Science article Birds Beware: The Praying
Mantis Wants Your Brain is a good read and is well researched. Apparently the larger Mantises have been documented to occasionally kill and eat (parts of) birds on six continents.
The…
uhoh
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