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1500 questions
15
votes
2 answers
Is there a specific word for fertile hybrids?
The way "species" has always been described to me is that a species is different if the two animals cannot have fertile offspring, with the caveat that language is imprecise and sometimes different species can produce fertile hybrids. For example,…
Curious Layman
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Can DNA produce ribozyme-like structures?
RNA is known to act as an enzyme via its ability to fold itself in specific ways.
Is DNA capable of such structures? Or is it some biochemical reason stopping the folding?
Have they been observed in nature?
John Smith
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15
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2 answers
Do photosynthesis and respiration violate the law of conservation of energy?
I don't know, if it's a physics question, biology or chemistry question but anyways here it is:
I have been taught that to produce one molecule of glucose in photosynthesis, 18 ATP molecules are used up, but that in respiration, oxidation of the…
Chahak
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15
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1 answer
Is it a limitation of the eyes, or the brain, that we can't see a moving bullet?
Are the photoreceptors in our eyes not fast enough to register the fast moving bullet, or is the brain not powerful enough to make sense of something happening that fast?
laggingreflex
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15
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2 answers
Which human cells have the longest and shortest lifespan?
Which cells in a human have the longest lifespan? Which cell has the shortest lifespan?
S.Sunil
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15
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1 answer
Why are more children being hospitalized with Covid-19?
I see that more children are being hospitalized with Covid-19. If I recall correctly, throughout the pandemic, researchers have thought that children were more resistant to the virus because they are often exposed to other viral pathogens, and…
Aaron
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15
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0 answers
Is it known how some heat-resistance Bacillus spores repair their DNA after having been heated to 420 °C? (but not much higher)
Background
Discussions below several recent posts in Space SE (links below) indicate that bacterial spores are a serious problem when considering how to prevent a future spacecraft mission to subsurface ocean worlds like Europa or Enceladus,…
uhoh
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15
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4 answers
Does RNA polymerase move around DNA or does DNA rotate beneath the polymerase?
I'm thinking of the human genome specifically, but more general answers are welcome.
As RNA polymerase moves along the DNA helix it follows a single strand. The two DNA strands are unwound locally by a helicase enzyme. However, after some…
Dave Gerrard
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15
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3 answers
Are there any motile plants?
There are numerous examples of sessile animals (sponges, barnacles etc.) but are there any examples of motile plants? If not, why not? Surely mobility would have conferred an evolutionary advantage to some plant species. I am specifically thinking…
Poshpaws
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15
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1 answer
Examples of animals that co-opt toxins?
It is known that there are animals that acquire toxins through their diet or through their surroundings. The examples I know of include butterflies stocking up on alkaloids/glycosides while in the caterpillar stage (monarchs snacking on milkweed…
user132
14
votes
1 answer
Are there specific conditions that allow humans to see ultraviolet wavelengths
It is fairly common knowledge that the lens in its normal state absorbs ultraviolet (UV) radiation. An interesting notion has come up from time to time in my reading that suggests there are a small number of conditions that result in humans being…
user3795
14
votes
1 answer
Are there phage-eating bacteria?
If phages (bacterium-eating viruses) prowl on bacteria, are there bacteria (or other micro-organisms) that hunt phages for food? They are rich in proteins anyway... Are there studies on this subject? Thanks
Gigiux
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14
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1 answer
What is the motivation behind the AAAAGCAUAU GACUAAAAAA of the mRNA SARS-CoV-2 vaccine when encoding its polyadenylated ending?
The very end of mRNA is polyadenylated as usual, but the BNT162b2 vaccine ends the following sequence, as denoted in this article:
****** ****
UAGCAAAAAA AAAAAAAAAA AAAAAAAAAA AAAAGCAUAU GACUAAAAAA AAAAAAAAAA…
Pedro D.
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14
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1 answer
Why do we add salt when precipitating DNA?
All the DNA extraction protocols I have seen involve adding salts to the extraction buffer. What is the purpose of the salts? What happens if they aren't included?
Rik Smith-Unna
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14
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1 answer
Do patella bones form in people born with the inability to walk?
The patella is a sesamoid bone that typically doesn't completely from and ossify until ~3-6 years of age (e.g., Source). My long-standing understanding (supported by a claim in Saladin's college A&P textbook1 sitting on my shelf) was that sesamoid…
theforestecologist
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