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1500 questions
21
votes
2 answers
How do fairy rings propagate?
It was somewhat new to me that mushrooms usually aren't individual organisms, but are merely the visible bodies of a bunch of fungi living in the soil. I know that mushrooms emit spores to reproduce, but what has been bizarre to me is how fairy…
user132
21
votes
2 answers
Why is Chromosome 1 called Chromosome 1?
Chromosome 1 is the designation for the largest human chromosome. Humans have two copies of chromosome 1, as they do with all of the autosomes, which are the non-sex chromosomes. Chromosome 1 spans about 249 million nucleotide base pairs, which are…
fu DL
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21
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3 answers
Why is wombat scat (feces) shaped like cubes?
I've heard that wombat scat is cube shaped, but I don't understand how that can happen. Has anyone studied the phenomenon? What would the evolutionary pressure have been to cause this?
ASimonis
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21
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Is there any convincing evidence for the existence of nanobacteria?
The existence of nanometer scale microorganisms has been proposed and used explain several phenomena including morphological structures in a martian meteorite (ALH 84001) and implication in the formation of kidney stones (1).
Is there now any…
Poshpaws
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21
votes
1 answer
What causes random long white body hairs?
I'm sure many of you have experienced this - you scratch your back or brush your hand over your arm and find a ridiculously long thin white hair, sometimes as long as 3 or 4 inches. I know a few people who get these quite frequently, and anecdotal…
Polynomial
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21
votes
3 answers
Why is the heart adversely impacted by chronic psychological stress, yet it benefits from routine physical exercise?
Chronic psychological stress is commonly said to be deleterious to the heart, and predispose one to cardiovascular disease. Yet the opposite is said about regular aerobic exercise. Physiologically, What is the difference between psychological stress…
froimovi
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21
votes
1 answer
Why do we feel tired if we sleep excessively?
When we eat, finally we feel full. I know which mechanism causes the sensation of being full. But when we sleep excessively we often still want more sleep. Why does this happen? Is there a mechanism underlying this?
MySky
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21
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4 answers
Alternatives to NCBI BLAST during US government shutdowns?
Many molecular biologists are used to going to NCBI BLAST for quick, hassle-free BLAST searches of their genetic or protein sequences.
However, during the last American government shutdown in 2013, BLAST was rendered unusable due to lack of…
March Ho
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21
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2 answers
What inactivates pepsin in infants?
In infants, rennin helps in digestion of milk. Pepsin is also present in their stomach.
Why do infants need rennin for milk digestion, at the first place? Why does pepsin not act on the milk proteins in infants? Does the production quantity of…
Mesentery
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21
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1 answer
What is going on in these cells?
Here are some pictures of human iPS cells in culture. After several passages, some cells look really weird, can you help me understand what is going on? What am I looking at? What are those blastocyst-like structures? (bluish picture) and what about…
alec_djinn
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21
votes
2 answers
What is this yellowish insect?
I found this insect inside of my shoe. It is approximately 1cm in length and less than half a centimetre wide. It was found in the Netherlands, in the province Gelderland.
Close shot
Distant shot
Upside down
What kind of insect is that?
Edit:…
Ebbinghaus
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21
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1 answer
What is this crawling next to my house?
I just found this outside my house while walking the dog. I was thinking it's some kind of slug? It's been raining a lot lately and today, so maybe that has something to do with it being on the pavement. I live in South Central Indiana, US. When it…
ansarob
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21
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1 answer
Is it painful for the hen to lay eggs?
My little son just asked me this question. His mother used to complain about the excruciating pain she suffered when she gave birth to him. He is a compassionate kid and wonders whether the hen goes through this pain everyday. Not being a hen, I am…
user768421
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21
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2 answers
Could viruses be used as antibiotics?
Could we use viruses that only affect bacteria to act as antibiotics?
The more bacteria, the more times the virus divides, so the stronger it gets. Is this practical?
Adam C
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21
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3 answers
Why does the face turn pale in dangerous situations?
I know what the effects are of a dangerous situation on the brain, i.e., an activation of the hypothalamic-pituitary-adrenal (HPA) axis which eventually results in an increased heart rate and elevated blood pressure. However, I do not understand why…
Probably
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