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1500 questions
14
votes
2 answers
Why do we like music?
Music is, of course, just a sequence of sounds. Sounds are vibrations in the air, which our ears detect. So why do we find certain sequences of sounds to be appealing? What makes us want to hear these sounds (turn on a radio, for example), or make…
Sir Cumference
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14
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How heavy are all foreign microorganisms in and on the human body?
I define "foreign microorganism" as a microorganism which is not produced
by the human body (not antibodies or leukocytes) including bacteria, viruses, fungi, biofilm aggregates or small lifeforms independent if they are benign or hostile.
Let's say…
user10094
14
votes
2 answers
How does a neuron change as you learn?
I am currently taking a course called "Introduction to Machine Learning with ENCOG 3", and I have a question about how well the Artificial Intelligence (AI) algorithm for a "neural network" corresponds with how an actual neuron works.
In the course,…
Greg Thatcher
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14
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1 answer
Can an organism exist as a single cell but come together as multi-cellular during certain times?
I am trying to remember a particular segment from a BBC special, about a single celled species. However, at certain times all the individual cells came together to form a structure, not unlike a mushroom, to scatter something like spores into the…
Daniel
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14
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2 answers
Why and how does uniprot list around 150,000 proteins in the human genome?
Using organism:"Homo sapiens (Human) [9606]" as a query in uniprot returns about 146,000 proteins. I was under the impression that there were only 20-25,000 protein coding genes in the human genome. Is this something to do with splice isoforms, like…
James
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14
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2 answers
Linear and Circular DNA
So school has taught us that eukaryotes have DNA that is linear and inside of a membrane - called the nucleus. And that prokaryotes have circular DNA that is free floating inside of the cell.
We also know the pros and cons of both linear and…
SolarLunix
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14
votes
3 answers
Why are the organs for reproduction and urinary excretion combined?
We eat food for getting energy to our body parts, and we excrete the wastes through urine, feces, and perspiration.
Why has nature combined the urinary tract with the genital system (urogenital system) in humans?
sagar
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14
votes
4 answers
Will the heart keep beating if it's separated from the body?
The heart is a vital organ in our body, as it drives blood circulation. I was wondering if a heart keeps beating if it is separated from the body? If yes, then why?
Shashank
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14
votes
1 answer
Solubility of DNA in water
This would seem to be an easy to answer question, but I was unable to find an answer (in g/L) for generic double-stranded DNA or plasmid neither on Google nor on BioNumbers. I would expect the solubility to vary slightly based on the sequence or…
March Ho
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14
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2 answers
The Uniqueness of DNA Paradox
How can everyone have unique iris and fingerprints? After a certain amount of human beings have lived on earth, wouldn't it be possible to exhaust all possible combinations?
The same principle applies to DNA. Lets say counting all the nucleotides…
Gordon
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14
votes
2 answers
Biopython - Big Discrepancy Calculating RNA melting Temperature over Literature
I experience big discrepancies when calculating melting temperature of RNA 7-mers with Biopython over values generated by a popular algorithm.
I tried the nearest neighbour algorithm with RNA and salt concentrations as described in a respective…
pykong
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14
votes
2 answers
Is the EC50 of an activating protein for an enzyme a good indicator for the binding affinity Kd?
We work with a membrane protein system where measuring the affinity between the enzyme and the upstream activating protein has been difficult, and when measured in detergent solution, it is almost 100 fold lesser (ie ~100nM) whereas the EC50 in an…
gkadam
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14
votes
4 answers
How many human proteins have a solved 3D structure?
I was wondering how many human proteins have a solved 3D structure. Is there a database with only human proteins? I looked at pdb but couldn't find a filter.
Gergana Vandova
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14
votes
2 answers
Do transcription factors bind to both strands of DNA?
Do transcription factors (or generally proteins) bind to only single strand of DNA or both strands? Since it can have non covalent bonds to both strands in theory. I would like to know the mechanism. Any reference books, papers or links will be…
dexterdev
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14
votes
2 answers
How can action potentials be generated through thoughts?
I think I understand how a signal is transferred from neuron to neuron (from How do the brain and nerves create electrical pulses?).
My question, however, is not about the standard textbook material on neuronal transduction. Instead, I am wondering…
CDB
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