Saliva moistens ingested food and it become a slick semisolid material called

humans can cause extinction of a species through overharvesting, pollution, habitat destruction, introduction of invasive species (such as new predators and food competitors), overhunting, and other influences. explosive, unsustainable human population growth is an essential cause of the extinction crisis.

explanation:

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the backbone of the dna and rna compound is sugar phosphate.