Final answer:
Tectonic plates are the divisions of Earth's crust and upper mantle, and their movement is caused by mantle convection. The plates can move apart, come together, slide alongside each other, or jam together.
Step-by-step explanation:
Earth's crust and upper mantle are divided into tectonic plates that fit together like pieces of a jigsaw puzzle. These plates are in constant motion. In certain areas, like the Atlantic Ocean, the plates are moving apart, while in others, like off the western coast of South America, they are being forced together. The movement of the plates is driven by the convection of the mantle, where heat escapes from the interior through the upward flow of warmer material and the sinking of cooler material.
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