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1500 questions
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Are there any examples of proteins with no or minimal sequence identity, but highly similar structure?
What are they, and do they share a common ancestor? How far back in evolutionary time must we go to find them?
If none are known, what computational tools might be used to search for such examples?
luminousfish
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Effect of pupil responses on the electroretinogram
The electroretinogram (ERG) is a measure of electrical activity of the retina. It is typically recorded from the cornea with a wire electrode or gold-foil electrode. Generally, the the ERG is considered to reflect the retinal processing of a light…
AliceD
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Are there birds with knees instead of elbows?
Are there any birds whose legs fold the same way human legs do, in a knee, instead of an elbow which is what all the birds I know have?
Violet Giraffe
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What is the contribution of viruses to the evolution of mankind?
I'm interested in horizontal gene transfer in bacteria, viruses, and organisms such as Bdelloid Rotifers. I've just read in Carl Zimmer's 'A Planet of Viruses' the following passage:
As a host cell manufactures new viruses, it sometimes…
Martin Foot
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How does translational coupling work in prokaryotes?
Today I heard about a phenomenon called "translational coupling", where the translation of one protein influences the translation of another protein. The messenger RNA levels don't seem influenced. How does this work? Do they need to be in the same…
Royco
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How long does a mosquito take to land on a host, bite, and fly off?
How long does a mosquito take to land on a host, start its bite, end its bite and then fly off?
And what about different species?
I am most interested in human hosts.
References to web sites or books would be appreciated.
I cannot find this even…
finch
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Did Darwin ever reach the conclusion that selection will remove variation?
According to simple models of selection the genetic variance in a population should be reduced by selection. (Fisher's fundamental theorem states that the rate at which a population can evolve is limited by its variance). If we select the next…
rg255
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Is there a biological mechanism for evolution encoded into our DNA?
Throughout high school, I remember learning about Darwin's theory of evolution as if it were near-fact. But something always seemed wrong about the ideas presented.
Survival of the fittest
Random mutation
Natural Selection
All of these things seem…
J.Todd
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Relationship between our microbiome and personalized nutrition
Recently, it has been asked whether there are 'metabolic types' between humans that can benefit from a sort of personalized nutrition. One answer suggested that one discerning factor could be the human microbiome. It is known that host–microbial…
Gianpaolo R
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Is there a correlation between total neurons and intelligence?
Thanks for looking.
First off, I am not a biologist, just a curious layman, so I apologize in advance if this isn't a "good" question. Please don't downvote me into oblivion.
I read today that the human brain has about 100 billion neurons and that…
Matt Cashatt
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What "emotions" can a snake feel?
Short:
Thinking in particular of a Royal Python (US: Ball Python) such as some people keep as exotic companion animals, what sorts of "emotions" or "feelings" are they capable of?
Long: http://simonsnakesite.tripod.com/snakebasics.html says…
ClickRick
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How fast will cells lyse under hypotonic conditions?
Routinely, lysis of cells with hypotonic solutions is carried out along with some physical (douncing) or enzymatic (lysozyme) method to break open the cells. If one were not to do any of these and just resuspend cells in water, how long would it…
gkadam
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How do we know that dinosaurs were related to lizards and/or birds?
Do we clearly know what the living closest relative of the dinosaurs are? And connected to the first question, in scientific manner how do we know these relationship between extinct species and living ones?
pikk
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How does a person get AIDS?
I am inquisitive to know about how a person contracts AIDS.
Among the common masses it's still the belief that having sex with multiple partners causes the disease but that is not the case when read online that it can come only from persons carrying…
munish
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Why do some fruits have a much wider range of acceptable sizes than others?
Some fruits such as pumpkins can grow to be 100 lbs. Under different conditions, the same variety of pumpkin can produce a 15 lb. fruit. Both plants are healthy, and look the same except for their size difference. If I took two red apple trees and…
J. Musser
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