Recent comments in /f/askscience

Oftwicke t1_j9b5q3i wrote

Reply to Can you control an animals movement with electric impulses to the brain and muscles? by Noobstompa6000

That would be very complicated, but essentially you could. You can already use electrodes to stimulate muscles for healthcare, re-education after surgery, or for bodybuilding. What you're suggesting through the brain is perhaps technically possible but impossible with modern science. Better to target motor neurons. Of course if you want it to make a normal, natural movement, you'll need to do the brain's work, and send just the correct amount of energy at just the correct frequency, which is an action potential. Ideally you'd find a way to stimulate the nerves directly like the brain or other nerves would rather than with electricity, you'd use neurotransmitters, but at this point you're just replacing the brain with a computer. This is complicated but not technically impossible. We just never made and probably never will make something that does that, and if we did it would take very, very long and doubtlessly we'd learn a lot of new things about nerves along the way that would be roadblocks for a time

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-Arke- t1_j9b5al5 wrote

Reply to comment by stronkreddituser in Why are we not acidic? by stronkreddituser

For starters, the previous answer can give you a general idea of how things are. That said, amino acid doesn't mean acid (or basic either).

An amino acid is a chain wich has a NH2 (basic) on one extreme and COOH (acid) on the other. So the actual PH of every aminoacid will deppend on the rest of the molecule.

But still, the actual answer would have more to do with what you've been told than it has to do with this, which is more of an anecdotic piece of knowledge.

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BeneficialWarrant t1_j9b4rem wrote

Reply to Why are we not acidic? by stronkreddituser

1: Amino acids contain both an organic acid and organic base.

2: The acid and base are both neutralized in the process of making a protein.

3: Some amino acids remain acidic or basic after becoming part of a protein because of extra parts they have on a side chain (sort of like a pendant or charm hanging down from a necklace).

4: Excess acid in the body is is neutralized by carbonate which can then be converted to CO2 and exhaled or filtered out by the kidneys into urine. There is baking soda in your blood and you can't survive without it.

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Oftwicke t1_j9b43ph wrote

Reply to How are places picked for “research”? by lala_blah

Local regulations and accessibility (not too far from the research lab) are big things, though you could find good other criteria like "people from many backgrounds from around here we can have a diverse sample", "people here usually respond positively"...

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aTacoParty t1_j9b2454 wrote

Reply to comment by stronkreddituser in Why are we not acidic? by stronkreddituser

100% correct!

And since carbonic acid/bicarb is the main buffer in blood, we regulate that by regulating our breathing. CO2 is converted into carbonic acid so by holding our breath (or breathing slower), we retain CO2 and decrease blood pH. Inversely, by breathing faster we blow out more CO2 and increase our blood pH.

Decreased blood pH is one of the main drivers for breathing. When you're swimming underwater and you start to feel the urge to breathe, it isn't lack of oxygen but rather the decreased blood pH from retained CO2 that your brain is sensing.

As a short aside, it's really bad for your blood to be more acidic OR more basic than ~7.4 pH. So when you see products claiming to "alkalinize" your body/blood for health, it's complete BS. Acids and bases are not inherently bad or good just like how hot and cold things are not inherently bad or good. I see these ads pop up pretty frequently, especially in fitness related settings and it drives me nuts.

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Lepmuru t1_j9b1knw wrote

Reply to comment by johndburger in Is toxoplasmosis life long? by Angel_thebro

Quite similar to infection with HSV-1 (herpes simplex virus type 1).

WHO estimates that 67% of people below 50 are infected worldwide. Still, you don't see 2 of 3 people regularly developing cold sores.

Infection with a pathogen does not necessarily mean showing signs of disease.

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aTacoParty t1_j9b1g34 wrote

Reply to What heppens to buprenorphine (or other opiods) after they have attached to the receptor? by Brandis_Black1994

As far as I am aware there is no such molecule. Opioids, like many ligands, bind receptors in a dynamic equilibrium meaning they are constantly binding and dissociating. Some are 'stickier' than others but none of them require enzymatic removal. The life cycle of the drug starts with high concentrations in your blood soon after taking it. It then diffuses down its concentration gradient into various tissues including the CNS where it binds mu opioid receptors to create an analgesic effect. As the liver removes it from the blood, the concentration gradient gets reversed with higher concentrations in the tissues and lower in the blood. So it once again diffuses down the concentration gradient back into the blood system where it gets removed.

Receptors may get endocytosed by neurons to prevent continued activation, but this doesn't necessarily remove the opioid from the receptor, it just prevents downstream signaling.

Dissociation of opioids from receptors (computation modeling)

https://pubs.acs.org/doi/10.1021/jacsau.1c00341

Endocytosis of opioid receptors after activation

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3683597/

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