In meiosis, crossing over occurs so there an be a genetic variation in the offspring. Genetic variation is vital to survival. In mitosis, crossing over would be a bad thing because the daughter cells need to be identical. Identical meaning the same genetic code. Therefore, crossing over wouldn’t be a positive process in identical daughter cells.
For much of the last quarter century, the leading theory of the driving force behind tectonic plate motions envisaged large scale convection currents in the upper mantle, which can be transmitted through the asthenosphere.
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forest cut down by a logging company</span>
