Answer:
You have external defense systems, which include your skin, tears, mucus, saliva, stomach acid, cilia (small hairs) and helpful bacteria. The skin, nails and hair form the integumentary system, which stops dirt and pathogens from entering the body.
There numerous of them but some of them would be contaminated soil which can be followed with altered soil chemistry that contains fewer soil organisms that are essential. The third one would be surface runoff due to extensively modified hydrology of the area.
1.Tyrannosaurus Rex Lived in the Mesozoic Era
2.The largest mass extinction happened in the Paleozoic Era
3.Life exploded for the first time in the Precambrian Era
4.The Chicxulub crater in the Cenozoic Era
Sand and glass have different chemical formulas, so that means that the atoms are rearranged and this is a chemical reaction.
