• appel@whiskers.bim.boats
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    2 years ago

    “eyebrow raising” indeed. Makes me think of the following questions:

    • Why is the amount of DNA in plants so much lower than in animal tissue? Is this because plant cells are larger? (some plants like wheat have very large genomes, I wonder how that affects it too)
    • Are cells lining the intestine replaced frequently? and which population of stem cells do they come from? this would reduce the affect, but I suppose, not eliminate it. If a mutation still occurred in a checkpoint gene, could that cell still become cancerous, even if it is terminally differentiated?
    • CrateDane
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      2 years ago

      > > Why is the amount of DNA in plants so much lower than in animal tissue? Is this because plant cells are larger? (some plants like wheat have very large genomes, I wonder how that affects it too)

      They are quoting the DNA concentration in g per kg of dry matter.

      Plant cells have cell walls of cellulose, hemicellulose and pectin, which adds some dry weight that is absent in animals.

      In addition, these seeds and tubers etc. we eat tend to be energy storage organs with a whole bunch of starch vs. not very much regular cell mass. It would be the same way if you ground up bone tissue and measured the DNA concentration.

      Are cells lining the intestine replaced frequently? and which population of stem cells do they come from?

      Yes, very frequently. There are stem cells in the crypts between villi of the duodenum, for example.