Scientific procedure to test a hypothesis. The outcome of the experiment either confirms or denies the hypothesis.

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56
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4answers
49k views

Death because of distilled water consumption

One of my friends said that I would die if I drank distilled water (we were using it in a chemistry experiment) I gave it a go and surprisingly did not die. I did a bit of Googling and found this ...
20
votes
1answer
650 views

Natural examples of XOR functions at the cellular level

We can often think of cells as a sort of circuit on macromolecules, and can show that they can accurately and robustly implement functions like $\text{MAJ}(x_1,...,x_n)$ (return $1$ if more than half ...
17
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1answer
34k views

Fish “coming back to life” after being frozen

I've encountered a clip on Youtube showing a goldfish thrown in liquid nitrogen and immediately after to normal water and swimming normally. In the explanation to the clip it says: For everyone ...
10
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3answers
6k views

Why is the number of PCR cycles limited?

I've been told that the maximum number of cycles in PCR is between 20 and 30. Is this true, and what are the reasons for this limitation?
6
votes
3answers
4k views

Why do grapes not shrink when placed in strong sugar solution?

I tried an experiment. First, I placed grapes in pure water(hypotonic solution). The grapes burst because of endosmosis. Then, I placed new set of grapes in strong sugar solution(fully saturated) but ...
5
votes
1answer
46 views

How are the physiological properties of mitochondria measured?

this is my first question on BiologySE. I am a Physics and Mathematics student currently doing a project on cell growth simulation. I am doing literature survey and I have a question about cellular ...
5
votes
1answer
186 views

Modern reference for Kropotkin's lazy bees

I have been reading through Peter Kropotkin's Mutual Aid: A Factor of Evolution and he mentions a curious fact about bees (bolding by me for emphasis): predatory instincts and laziness continue to ...
5
votes
2answers
2k views

What would cause proteins to get stuck in the stacking layer of a SDS-Page gel

Typically when proteins aggregate, they will get stuck at the top of the well. However, we're seeing some protein aggregate in the stacking layer even when we're treating the loading volume with DTT. ...
4
votes
1answer
68 views

Productive turnover and generations in the fruit fly

I was reading about the Lenski experiments on the evolution of E. coli bacterium and Dr. Elders's experiments on the evolution of the guppy. These two experiments absolutely fascinated me, and seemed ...
3
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2answers
2k views

What is an 'ex vivo' experiment?

Simple terminology question: Is there a hard boundary between in vitro and ex vivo? Is there a hard boundary between in vivo and ex vivo? Suppose a sensory neuron is electrically recorded in the ...
3
votes
1answer
75 views

Why are pharmacology studies so experimental?

I am a med student, and as far as I see from our pharmacology lectures, pharmacologists work almost completely experimental. Quite typically they take a substance (e.g., from nature), they add, change ...
3
votes
1answer
607 views

Questions regarding ELISA

I have recently peformed an ELISA (Enzyme-linked immunosorbent assay), but I still have some questions, let me first outline what I did: We had a number (20) of tubes containing fake 'bodily fluids' ...
2
votes
2answers
762 views

What does “delineate” mean in this context?

I was reading a Scientific American story, “Controversial Spewed Iron Experiment Succeeds as Carbon Sink” (by David Biello), when I came across this sentence: “The problem for scientists is that ...
2
votes
1answer
6k views

How difficult is to renature a protein?

I know of Anfinsen's experiments and I'm aware that some denatured enzymes may regain their lost activity through the removal of the denaturant agent. What I'm unaware of is how rare is it for a ...
2
votes
2answers
313 views

Are there natural selection experiments that quantitatively agree with theoretical modeling? [closed]

Has anyone ever conducted an evolution experiment and quantitatively compared it to theory? For example, has anyone ever put bacteria in a million petri dishes filled with antibiotics and calculated ...
2
votes
1answer
50 views

How long can a plant generate oxygen from its own carbon dioxide, produced during nighttime?

I recently bought one of these miracle fruit plants (Synsepalum dulcificum). Since they are of tropic origin, they need higher humidity and temperature as we have it here in Austria. So I decided to ...
2
votes
2answers
138 views

Image analysis of GFP-tagged protein localization bursts

I'm reading an article (full text here) that analyze the dynamics of localization of a GFP-tagged transcription factor (Crz1) over the time at the single-cell level, by taking movies in a fluorescent ...
1
vote
0answers
28 views

Estimating RNA concentration from Specific Activity of Labeled RNA

The question reads, Using T7 RNA polymerase to transcribe in vitro a 100-nt RNA off a DNA template. This RNA contains 19 Adenosines. In your 100 uL transcription reaction you added 1.00 µL of α32P•[...
1
vote
0answers
38 views

Is it worth to experiment with pro-biotics at home?

Let's assume that Joe has done some investigation on Internet and wants to see, if pro-biotics would help him. Now he goes to amazon.com and buys a pro-biotic product with excellent average rating. ...
1
vote
0answers
40 views

Is there a better lysis buffer than this for fungal DNA extraction?

I've being using this lysis buffer for fungal DNA extraction,lysis buffer - 400mM TRis-HCl(pH8.0), 60mM EDTA(pH8.0), 150mM NaCl, 1% SDS and containing 40microgram/ml RnaseA. It is keep giving very ...
0
votes
1answer
56 views

Growth Hormone and diabetes

Growth hormone and insulin like growth factors are diabetogenic, so I assume that people with high growth hormone (say due to pituitary tumor) may be at high risk for diabetes. Has any correlation ...