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1500 questions
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1 answer

Can siRNA induce DNA methylation in mammalian cells?

Some years ago Hiroaki Kawasaki and Kazunari Taira published an article called "Induction of DNA methylation and gene silencing by short interfering RNAs in human cells" in Nature: In plants, dsRNAs targeted to CpG islands within a promoter can…
Mad Scientist
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What is the difference between HPLC and FPLC and why is FPLC preferable for protein purification?

I've used HPLC (high performance liquid chromatography) before (once, so I'm barely even qualified to know what it stands for) so I was surprised when my labmate told me she would be using an alternate technique to isolate a protein. What exactly…
Emmie MC
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Regulation of chromatin structure

Recently, I reviewed the different levels of chromatin structure. The primary level is nucleosomes, where DNA is bound to histones, and has structural similarity to "beads on a string." The secondary level is a 30nm fiber, and the tertiary level is…
Daniel Standage
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Why is China experiencing such a surge in acute cases of COVID?

The majority of western nations have lifted most if not all COVID restrictions, however we are not seeing a massive rise in serious cases of COVID-19. Why is it different in China? Do they have a different strain?
moshevi
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Can 'human' become a genus due to space colonization?

I have read that during the Second World War, some mosquitoes got trapped in the London underground railway system. The mosquitoes never got out and eventually they became a new species by themselves. I had a similar thought. In the next few…
PNS
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Why don't we have vaccination against all diseases caused by microbes?

People can be vaccinated against certain diseases. Principle of vaccination is to use live attenuated load or inactivated. My question is - why we dont have vaccination against all diseases which are caused by microbes?
akm
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Do marine deep sea life forms exhibit circadian rhythms? If so, what entrains them?

I've been reading a lot about circadian rhythms, when suddenly this question popped into my head: do circadian rhythms exist for deep sea organisms (3000 ft / 1000 meters+)? For land mammals, the entrainment of circadian rhythms is done through…
Alex Stone
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Are mutations a source of genetic variation?

Here is a question from the book SAT II Success Biology E/M (where the SAT is the exam taken by the American high school students): Which of the following statements is true about mutations? (A) Rates tend to be very high in most populations. …
Elena Kolumba
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Can plants get cancer?

I can't think of any reason why plants wouldn't be able to get cancer, but I've never heard of a plant growing a tumor. I've also never seen a plant with a noticeable abnormal growth. Can plants get cancer?
Orcris
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Why have a placebo control group when testing a new drug if existing drugs can be used?

It is general practice to compare a new treatment against a sham treatment (placebo), and then use those results to compare efficacy of the new treatment (call it B) to an existing treatment (call it A), at least when existing treatments are…
Daniel Goldman
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How will rising carbon dioxide levels in the troposphere affect photosynthetic producers?

Much discussion has been had about the affects of climate change on plantlife, but how will rising carbon dioxide concentrations affect the photosynthetic process itself? Since CO₂ is a reagent in photosynthesis, would we expect higher CO₂ to mean…
Poshpaws
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Why does the insulin taken from pig when injected into humans causes allergy but not the insulin taken from bacteria?

At earlier times, insulin was injected to human patients that were taken from pigs and horses. But that caused allergy it seems. But why is the insulin produced by the recombinant bacteria not causing such types of allergy?
Kawin M
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How did the largest/longest dinosaurs hold their head and necks up?

After seeing the images in the articles shown below, I am having a tough time understanding the mechanics of how these incredibly long and heavy necks can be supported outstretched like this. A rigid beam or tube would remain fairly straight through…
uhoh
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Are there any animals that celebrate communally?

Are there any animals that are known to celebrate events? For example, we humans might celebrate a birthday or passing an important test. An event causes us to perform some sort of celebration that is motivated simply by joy and not any sort of…
Bryant Makes Programs
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Why do some mammals not have testes in a scrotum?

Coming from an evolutionary approach, Is the only purpose of a scrotum to regulate the temperature of the testes? Knowing all mammals are warm blooded, shouldn't all mammals have testes in a scrotum?
Gabriel Fair
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