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1500 questions
15
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2 answers
Why does the protection afforded by some vaccines last longer than for others?
After reading an answer to the question of How Do White Blood Cells Learn? Or Do They?, I came to wonder something. Specifically,
The effect of this is that every new B and T cell that your bone marrow makes will recognize a unique, random protein…
Cat
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15
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3 answers
Is there a fundamental reason that plants cannot fix their own nitrogen?
Plants must have nitrogen to grow. According to the answer to this question, there are no plants that can fix their own nitrogen (without the help of bacteria).
Plants get their nitrogen in the form of nitrates (NO3-) or ammonia (NH4+). Nitrates and…
Volker Siegel
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15
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6 answers
Can the human brain be reduced to a binary system?
Does the brain really function like a computer as in, ultimately every response is related to a binary sequence based on whether particular neurons fire or not?
greenMamBa
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15
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1 answer
What are the requirements for a stable carbon cycle in sealed "bottle gardens"`?
The most famous example of a sealed bottle garden is David Latimer's bottle with a Spiderworth plant, pictured below, which has been sealed for 40 years. My own attempt at a bottle garden is failing and I'm looking to "debug" what's going on.
My…
Abulafia
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15
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2 answers
Why I have to pee more often in low temperature?
I realised that I have to pee more often in winter or simply the temperature is low. Is there any scientific explanation, or just simply psychology?
blackcornail
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15
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1 answer
How does this illusion work?
I found this image on Google+
If you shake your head you can see a portrait of a person. Can anyone explain how the image is constructed in the brain?
Green Noob
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15
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Species ID: Cape Town mystery insect
This insect bumbled into my bedroom last night - can someone ID it for me? I'm mainly curious because I'd like to know if it poses any danger to my cats (who were very eager to add it to the menu).
It was about an inch and a half to two inches…
Viergacht
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15
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1 answer
Why doesn't HDL cause diseases like LDL?
LDL particles pose a risk for cardiovascular disease when they invade the endothelium and become oxidized, since the oxidized forms are more easily retained by the proteoglycans. A complex set of biochemical reactions regulates the oxidation of LDL…
user12874
15
votes
1 answer
Why do flies "rub" their front legs when resting?
I've noted that every time a house fly is resting on a surface, it appears to "rub" or "scrub" its front legs in a repetitive movement. And they do it continuously. Why?
Damián Gil
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Is the function of adjacent genes correlated?
Do genes that occupy a similar locus on the genome have correlated function, specifically in human beings? It is my understanding that adjacent genes are inherited together, and so location plays a role there. However it terms of function, I don't…
user4673
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3 answers
When has an organism evolved enough to be called a new species?
Imagine that we take a population of horses, split them in half and place them in completely different environments. The two species will evolve separate from each other and because the environment is different, the outcome of evolution will be…
Simon Verbeke
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Formation of Life
Originally, life evolved from non-living matter. Why is life only generated from other life nowadays, and why doesn't it evolve from inanimate matter, like it did originally billions of years ago, when life evolved on Earth?
Maybe I should reword…
Peter U
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2 answers
Do electromagnetic waves outside the visible spectrum have any role in photosynthesis?
Does photosynthesis occur only in the visible spectrum? If there is a way to completely remove all other electromagnetic bands from the sunlight, including infrared (IR), will photosynthesis continue to occur?
Is there any known plant (algae, fungi,…
One Face
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15
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3 answers
How many cells does the smallest animal have?
Note: question rewritten to prevent misunderstanding and make it more answerable
I know that some small animals like C. elegans display surprising sophistication with a very small number of cells. But I wonder, among the animals with known/estimated…
rumtscho
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15
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5 answers
Why did high A+T content create problems for the Plasmodium falciparum genome project?
The main paper for the Plasmodium palciparum genome project (Gardner et al., 2002) repeatedly mentioned that the unusually high A+T content (~80%) of the genome caused problems. For example they imply that it prevented them using a clone-by-clone…
Rik Smith-Unna
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