18 votes
Accepted

Why is the retention of ability to synthesize non essential amino acids of negative survival value?

It’s a very dubious argument in my opinion. Whenever I see a question on this list arguing that higher organisms could save energy and DNA by such-and-such a hypothetical construct I want to scream. ...
David's user avatar
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6 votes

Why is the retention of ability to synthesize non essential amino acids of negative survival value?

The passage is saying that if you get enough of a nutrient in your diet, you don't need to synthesize it. If you don't need to synthesize a nutrient, you don't need to waste energy on the machinery to ...
Bryan Krause's user avatar
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6 votes
Accepted

Is it viable to make liquid potassium ferilizer through dissolving very small amounts of potassium chloride in water

the issue here is the chloride not the potassium. Potassium chloride is very soluble in water. but you could be killing your crops/garden when you spray it on. Most plants do not tolerate much ...
shigeta's user avatar
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4 votes

Is it possible to live without iodine? (sea plants, seaweed or fish?)

Iodine is a component of the thyroid hormones, thyroxine and triiodothyronine, so it is indeed a human nutritional requirement. According to this Harvard University webpage, milk (especially), eggs ...
David's user avatar
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3 votes
Accepted

If protein is mostly used by the body for purposes other than extraction of energy, why are calories from protein relevant?

Preamble I had not intended to answer this question as I felt it lacked the clarity required for this site. However I now think that it is necessary to correct the assertion that “protein has to be ...
David's user avatar
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2 votes
Accepted

How is it known that there are only three macronutrients: proteins carbohydrates and lipids?

Summary The question is based on the misconception that the term “macronutrient” originated as a scientific definition, to which entities satisfying this definition were assigned. In fact it was a ...
David's user avatar
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2 votes

Why is the retention of ability to synthesize non essential amino acids of negative survival value?

I don't see the cost of the synthetization machinery as relevant (in this case), either. There is selection pressure to turn off the production if it's not needed, since leaving it running would ...
user66554's user avatar
  • 151
1 vote

Searching for reference regarding the impact of famine on a woman's grandchildren

Here's an article in Science about the phenomenon: https://www.science.org/content/article/moms-environment-during-pregnancy-can-affect-her-grandchildren It references a variety of different studies, ...
Bryan Krause's user avatar
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