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Why is the opposite of plantar flexion called "dorsiflexion"?
Why is the action of flexing the foot so that the toes move anteriorly/superiorly (i.e. in the direction opposite that which they move during plantar flexion) described as "dorsiflexion?" In the same vein, why is the top surface of the foot called…
senshin
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Are there any side-effects from a mosquitoes extinction?
Suppose that we have the ability to make mosquitoes extinct, what would be the likely effects (on disease and ecosystems for example) of such extinction? Essentially, what roles in nature do mosquitoes perform?
user10037
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Why do human eyes glow red on a photo and dog's eyes green?
Previous Research
I know that cameras sometimes come with an anti "red eye" functionality that involves two flashes, presumably the second flash coincides with the shutter opening.
Question
Why do camera flashes sometimes lead to photos of humans…
hello_there_andy
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What senses are active while sleeping?
During sleep, our body activity decreases. I am wondering on the extent of the lowering of this activity regarding our five senses. Clearly, the sense of touch is still very efficient since shaking a body is the most common way to awake someone, and…
Taladris
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How does the molecular machinery choose where to cut a chromosome for recombination?
I'm wondering about a few technicalities of crossover in meiosis. The point of crossover is to create new chromosomes that don't have the same allele combinations as the original two chromosomes. Usually, the chromosomes are cut at the same place on…
Pertinax
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Are codons that map to the same amino acids interchangeable?
From wikipedia, in the section on the RNA codon table, I see a mapping between codons and amino acids. There, Valine is related to GUU, GUA, GUG, GUC.
Does it mean in the same context that these four codons are interchangeable? Could one replace…
Yehosef
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Does a man contain all the genes needed to make a woman?
This question is brought on by a Sci Fi novel I am thinking about writing. The plot device involves a colonist in charge of building a population on a new planet who loses his supply of embryos and so forth in the landing. With the artificial…
wedstrom
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Why do we experience temperatures below 37 degrees Celsius as 'hot'?
We always prefer to be in 20-25° C, although our core temperature is about 37°? Why is our skin temperature lower than our core temperature?
user12874
13
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2 answers
Do men have significant hormonal cycles?
I know there's a similar question here. But that discussion dissolved into lunar cycle and a correlation with it. I want to find more towards the original question of is there a periodic hormone cycle in men.
The links i have read suggest that…
Software Mechanic
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Why can blood group O be given to all blood groups?
The blood of persons of blood group O contains antibodies against antigens A and B. The red blood cells of persons of blood group A have A antigen on their surface. If someone with blood group A receives blood from a donor of group O, then anti-A…
Nick
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Why do we have two of some organs, but not all?
We have two eyes, but we don't have two hearts.
Why do humans have two of some organs, but not all?
user10246
13
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5 answers
Do human cells contain only one copy of the genome?
Does each cell contain only a single copy of its genome? Or are there ever 'extra' copies present.
Reason behind question: Wondering whether gene mutations could be corrected by referencing a 'backup copy'.. If such a thing exists..
user9915
13
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How do insects survive the winter?
I had an interesting discussion today in which the question arose how insects survive in the winter. Since they need a high enough external temperature to be active, this seems a bit difficult in the winter. With frost they should completely freeze…
Chris
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What makes E. coli yellowish?
LB, TB media, and yeast extract are also yellow but at the heart of the question. What chemical(s) make E. coli yellow?
bobthejoe
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How does an embryo know where to grow limbs etc
For example you have a cell or already a bunch of cells. Those cell(s) divide and after several week you have a grown organism, for example a human with limbs, several different organs etc.
However, how do cells know where up, down, left, right…
Imago
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