Question

explain, why we humans can not digest grass but can digest grass​

Answer 1

Answer:

Grass also contains a lot of silica, which is abrasive to human teeth. Grazing animals have teeth that can re-coat their own surfaces continually, so the silica does not affect them. Because humans are unable to digest grass, they can get almost no nutrition from it.

Explanation:

Answer 2

Answer:

Humans can't digest grass because we don't have those microbes to produce the enzymes we'd need to break down cellulose. pH of your stomach is normally around 1 to 3, which is very acidic. The pH of the rumen, where the grass-digesting microbes live in cows, is closer to a more neutral.

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