Ionic bonds result when electrons are tranfered between atoms. Covalent bonds result when valence electrons are shared between atoms. You should be able to identify whether an ionic or covalent bond is being formed between atoms.
        
             
        
        
        
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In Late 1600s Anton von Leeuwenhoek develops a more powerful microscope that allows him to see living cells like bacteria.
In Early 1800s Matthias Schleiden and Theodor Schwann conclude that all living organisms are made of cells, and that cells can be produced from other cells.
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Answer:
A decrease in biodiversity causes a decrease in ecosystem stability, because a change to one organism will have a greater impact on the entire ecosystem. With greater biodiversity, the loss of one type of organism could be moderated by the adaptation of other organisms to fill its role.