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What is the term for "technical extinction" of yet alive animals?
What is the term for an event in which a species is still alive, but has no chance of future reproduction and the species will be considered extinct once the current generation dies out?
For example a species of a tiger that has the last 5 surviving…
Pringles
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Why does size decrease across the sequence of human chromosomes?
The following graph shows a decrease in the number of base pairs per chromosome across the sequential set of human chromosomes:
Is this because chromosomes were originally numbered by their size on the karyotype?
SANBI samples
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How do large herbivores get enough protein?
The food they eat seem extremely low on protein. Do they need less protein per mass unit than carnivores? Most of them grow quite a lot in the first year, is most of that from the mothers milk?
Euphorbium
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Abiogenesis: Beyond the research journals as a lead in to discussions on evolution
I just came across this abstract:
Aminoacyl-tRNA synthetases (aaRSs) are responsible for creating the pool of correctly charged aminoacyl-tRNAs that are
necessary for the translation of genetic information (mRNA) by the ribosome. Each aaRS…
Larian LeQuella
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How do CpG islands remain unmethylated?
In most of the genome CpG sites are pretty much always methylated, but CpG islands are instead often unmethylated. This has been linked to the fact that they often are associated to transcripted genes.
What are the current theories on the…
nico
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How can frogs tolerate freezing while humans cannot?
A wood frog can tolerate the freezing of their blood and other tissues. (wiki, news2), but human beings can not.
Some people plan to freeze their bodies/brains after death, and some of them have done that.
Can wood frogs help us learn how to freeze…
questionhang
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Does DNA react in all of the ways most other acids do?
As I understand it from my basic chemistry, there are some fundamental reactions that exist between any acid and other substances for example acid-base reactions that form a salt, and the existence of a state of equilibrium in water.
Do these…
Matthew Higgins
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Two different Leucochloridium infected snails - different species?
In the last three days, I have found two snails infected by some species of Leucochloridium. I found them in my garden in the south-west of Sweden. Now I'm wondering if they are the same species or not.
One has broodsacs with green stripes and…
picapica
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What limits chromosomal length?
What are the upper and lower limits for chromosome length? Are these limits different in different species or kingdoms? If there is any limit, which cellular or molecular factors are reasons?
MySky
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Is there a name for the evolutionary loss of vestigial structures?
Consider a biological structure which no longer benefits an organism, such as the eyes of an organism whose population now lives in total darkness. I can think of three reasons why such a structure might disappear:
0) Random changes to the…
Trixie Wolf
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Do twins "run in the family"?
My wife and I recently found out that we are going to have twins and so nearly everyone asks if we have a family history of twins. Now I know that the answer for me is that it doesn't matter—as a man, I have no influence on my wife's tendency to…
Jon Ericson
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Can we make a rough estimate of the number of generations since the origin of life?
According to what we've learnt :
we can approximate the number of generations since the first human pretty much like us (depending what / who we talk about).
we have an idea of the series of life forms we come from.
So is it possible to give it a…
Thibaut
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Why are people unable to develop lasting immunity against Norovirus?
Infection with many viruses will result in decades-long if not lifetime immunity, for example chicken pox.
Because of the large number of viruses responsible for the common cold, lifelong immunity to the common cold isn't possible; we will still be…
anongoodnurse
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What is the purpose of gluconeogenesis?
The gluconeogenesis pathway seems quite pointless to me. I don't understand why an organism would want to spend energy to create a molecule that can then be metabolized again for less energy? The pathway seems only to serve as a complete waste of…
Paze
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Should we induce fever to assist healing?
I am currently reading "The Fundamentals of Anatomy Physiology" 10th edition, and have found it an incredibly interesting book. I have just been reading about the lymphatic system, and the various Leukocytes and their roles. When it mentioned fever…
Stevo
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