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1500 questions
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3 answers
How compelling is the hypothesis that dinosaurs were killed by toxic plants?
A friend of mine has recently told me that dinosaurs were "killed by flowers". I was a bit surprised and so I googled. And I did find a lot of recent articles in popular media on this topic, probably based on this. To me it doesn't sound convincing…
Alexis
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Can spider silk be synthesized to be used for 3D printing?
With the recent rise in 3D printing, I keep hearing about more novel ways to use the technology: cell 3D printing, liquid aluminum or plastic 3D printing. For example, this Ted talk deals with printing a human kidney. What interests me is if the…
Alex Stone
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Which sequence characteristics influence the transcription efficiency of T7 polymerase?
The T7 polymerase doesn't transcribe all sequences equally well, the transciption efficiency can vary widely for different sequences. One well known requirement of the T7 polymerase is that the sequence should begin with 2-3 guanines for efficient…
Mad Scientist
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12
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I am trying to identify this plant
I am trying to identify this medium arching shrub growing to about 1.5m high x 2m wide in the subtropical climate of the Mt Coot-tha Botanic Gardens in Brisbane, Australia. Unfortunately there was no label with it. The inflorescence is about 3cm…
Solveig Gillis
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12
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Did the construction of the Panama Canal lead to a huge change in the local marine ecology?
Before the Panama Canal opened in 1914, its two ends were only 77 km apart over land, but the closest sea route was 32,000 km long (around the entirety of South America) and passed through much colder waters near Cape Horn. Therefore, I suspect that…
tparker
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Are drones from one honey bee queen all clones?
The Honey Bee queen lays eggs that develop into worker bees (female) if she fertilizes the egg. If she does not fertilize the egg, it will develop into a drone (male).
The drone only has the queen's DNA so are all drones exact copies of each…
M Grindley
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4 answers
Are humans Gnathostomates?
Gnathostomates are vertebrates having jaws. But when I search on the internet for Gnathostomates, I always find out that they are sharks and fish-like organisms.
But are humans not also Gnathostomates? Don't we have jaws?
Taylan
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12
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Systems identification in small neural network
When analyzing data from cortex, we often try to understand what each neuron does in terms of its inputs from other neurons - a specific kind of a systems identification strategy. Most current approaches use generalized linear models for that…
Konrad Kording
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12
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2 answers
Why aren't 'exons' named 'introns'?
Why are introns called 'introns' when they are the actual ones who are getting spliced out from the pre-mRNA. Shouldn't exons be named introns as they are the ones that are 'in' and are not 'exiting'? On what criteria were they named like this?
Jewel Johnson
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4 answers
Why are 3 nucleotides used as codons for amino-acid mapping in DNA?
DNA is made of 4 unique nucleotides. When coding for a protein, a sequence of 3 nucleotides is used to code for each amino acid. Why are codons 3 nucleotides in length?
A related question can be found here:…
Luke
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What prevents a pregnant woman's immune system from recognizing her fetus as nonself (and attacking)?
I'm familiar with the scenario of Rh- mother with Rh+ fetus having complications (more so after her first child), but that's not what I'm curious about. I want to know mechanistically why a pregnant woman's body does not display a reaction similar…
yelx
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2 answers
Red bug with white tips on antennae
These red bugs can be found in hundreds in our locality in Bangalore, India.
They are just about 3.5 cm and have these white (or maybe pale yellow) tips on their antennae.
Can someone identify them and suggest a link where I can find substantial…
AdDate
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Why doesn't a substance like loperamide promote analgesia?
Loperamide is frequently used to slow gastrointestinal motility. It is available over the counter (in the US, I don't know about elsewhere) without any regulations whatsoever, yet it's derived from an opiate. Knowing that the opiates slow the…
jonsca
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12
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5 answers
Are there known life forms that are able to transform mechanical energy into chemical energy?
Are there known life forms that are able to transform mechanical energy into chemical energy?
This question asks a similar subject, but more specific and has no answers.
The background of this question are thoughts about hypothetical life on tidally…
user21844
12
votes
1 answer
Does bioluminescence occur in humans too?
I read that Japanese researchers have developed very sensitive camera that recorded bioluminescence in humans; is it possible and if so what is the mechanism behind it?
Ebvirus
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