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stronkreddituser OP t1_j9b0kbv wrote

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

I see how vague my question is now lol. Primarily, I was asking why any part of the body made up of proteins would be alkaline, but now I know that it is not as simple as "amino acid = acidic pH".

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-Arke- t1_j9b5al5 wrote

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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aphilsphan t1_j9b8qyi wrote

To add a bit, an amino acid can and will protonate itself. So the COOH (carboxylic acid) group “loses” its hydrogen as an ion (called a proton by chemists because that’s what it is). This results in the pronation of the amine (NH2) group. So you’ve got COO- on one end and NH3+ on the other. This is the “zwitterion” form.

Lots of chemistry is learning the vocabulary because the vocabulary makes it easier to communicate quickly.

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911derbread t1_j9emepg wrote

Hey! I'm a doctor and a biochem nerd. Your blood pH is buffered by multiple systems, primarily bicarbonate, as well as lactate and phosphate compounds. That means that swings in the concentration of blood compounds (aspirin, or salicylic acid, for example, is an acid) don't cause significant changes. pH is also tightly controlled by your lungs and kidneys. Your lungs control the amount of CO2 in your blood, and therefore bicarb and carbonic acid content. Your kidneys also retain or excrete bicarb as needed. There are certain processes like lactic acid production, electrolyte abnormalities, and kidney or lung issues that can make you relatively acidic. However, a truly acidic pH of even slightly less than 7 is a pretty profound acidosis and likely life threatening.

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