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1500 questions
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What kind of event would cause the current Mitochondrial Eve to be replaced by a new one?
Apparently all living humans are matrilineal descendants of a single woman who lived 200.000 years ago. She is called Mitochondrial Eve.
But at the time she lived there was a different matrilineal ancestor that all living humans shared. And between…
molf
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Quinone A, Quinone B, Ubiquinone, Plastoquinone: whats the difference?
I am getting very confused about this. My understanding so far is that ubiquinone is used as an electron (and proton) carrier in oxidative phosphorylation in the mitochondria whereas plastoquinone is the carrier in the light dependent reaction in…
Meep
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11
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Insect identification request
I live in France. I've just found several (8) of these in my living room, close to an oak cupboard and my Christmas tree, a cut Abies nordmanniana (supposedly grown in France).
Their body is around 5 mm (1/5 in) long. On the tissue they walk easily…
L. Levrel
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11
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What to look for when buying a light microscope?
I am a science lover and want to buy a microscope to explore things around me. Like studying cell structures, microorganisms, blood and plants. It would be great if there is way to photograph slides. Just curious to know and explore things around…
Pankaj Phartiyal
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11
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Does the DNA sequence of a butterfly match that of the caterpillar it used to be?
Just had this thought occur to me.
If one were to take a DNA sample(or is it RNA?) of a caterpillar before it became a chrysalis, and attempt to match the sample against one taken after the chrysalis matured to a butterfly, would the two samples…
Everyone
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11
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3 answers
How much weight/volume do microbes occupy within the human body?
Microorganisms constitute the bulk of all the biomass on Earth. I weighed myself yesterday, and wondered how much less I would weigh if I were completely free of bacteria and microbes, inside and out.
Approximately how much weight and volume do…
LanceLafontaine
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11
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How do neurons form new connections in brain plasticity?
I've been reading about brain plasticity and how the brain can "rewire" itself.
One of the things that is not clear to me - how neurons can establish new connections. Does this rewiring mean that neurons can "disconnect" from other neurons to reuse…
Alex Stone
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11
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Do crocodiles age?
I was watching a talk by Michio Kaku and he mentioned that crocodiles (or possibly alligators, I forget offhand) don't actually age -- they can die, but they essentially go through no aging process beyond adulthood
Can anyone link me any sort of…
sarah
11
votes
6 answers
What makes humans omnivores, and not herbivores?
Some vegans claim that humans are herbivores, not omnivores, and that we are not physiologically designed to eat meat (see here: http://www.peta.org/living/food/natural-human-diet/).
"According to biologists and anthropologists who study our…
Big Skeptic
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Why are the Galápagos islands so special?
Why did Darwin formulate his theory of evolution just after his visit to the Galápagos islands? Why were they so special from an evolutionary point of view?
emanuele
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What is the rationale behind tapering of immunosuppressant dose a while after transplant?
MMF, Cyclosporine, Prednisolone, Tacrolimus the dose of whatever immunosuppressant used is reduced in around 6 months - 1 year after the transplant.
What is the rationale behind this?
Wouldn't any allograft, howsoever old, still remain foreign?…
Polisetty
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11
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2 answers
What is/are the molecular differences between HDL and LDL cholesterol?
Why exactly is HDL-cholesterol good for us and LDL-cholesterol bad for us. It has been well-established that LDL-cholesterol is associated with atherosclerosis and that HDL-cholesterol helps remove excess LDL-cholesterol from the circulation. From a…
JohnPhteven
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1 answer
What causes this acorn disease?
This year, many acorns in our area (Germany, Schartzwald) fell prematurely, plagued by some kind of warts or gall-nuts which I see for the first time:
Some of the acorns are covered by two or three warts at a time, so that the actual nut itself is…
Dmitry Grigoryev
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1 answer
What are the "stars" we see after a bump on the head?
Sorry if this might appear funny. When I close my eyes for a longer time, and suddenly open it, I see some twinkling white small circles, and when i concentrate on anyone of them it disappears, as if the image is falling on the blind spot.
This…
gpuguy
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Can Bioluminescence drive photosynthesis?
I'm trying to construct an anaerobic kitchen-waste digester at home.
The major output from the digester is methane - with a significant component of carbon dioxide. To scrub/reduce the CO2 I was thinking of passing the methane through a freshwater…
Everyone
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