Answer:A
Explanation:
because optimistic people are confident about their future
Our skin cells divide rapidly in order to maintain a protective barrier against infection.The outer skin layer is called the epidermis and contains mostly dead cells that contain keratin.Keratin is a tough fibrous protein found in hair,skin and calluses and acts as a protective coating.The epidermis cells are constantly undergoing mitosis so the outer dead cells containing keratin are rapidly replaced as they fall off, which occurs after so many days.Then the newer living cells start producing keratin,lose their cellular contents,then die and the cycle goes on.The skin acts as a barrier to infection,therefore,it's constantly renewed and repaired.
They converted carbon dioxide to oxygen. The increased oxygen levels allowed for cellular respiration to occur instead of only glycolysis. The atmosphere became thinner, decreasing temperatures of the planet as well.
Answer:
They can destroy the ecosystem or out - compete a native species.
Explanation:
For example, if an invasive species of tree is taller than the native species of tree and therefore takes up more sunlight, leaving the shorter native tree not enough sun, then it will effectively kill the native tree.
Also non - native and invasive are not the same thing. A non - native species doesn't necessarily mean it's invasive. It is only invasive if it begins to have a significant impact on the ecosystem it is inhabiting.
