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At the center of the Milky Way Galaxy, there is a supermassive black hole. This is normal — at the center of almost every galaxy there is a black hole that is millions or billions times heavier than our sun. As galaxies move through the universe, they occasionally collide (the Milky Way is currently colliding with…

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When we first learn about cells in biology, we are taught that bacterial cells are simple, and animal and plant cells are more complex. Mammalian cells, the cells that make up dogs, humans and all mammals, are “eukaryotes.” Eukaryotes have multiple membranes — one surrounding their innermost section, the nucleus,…