The purpose of the coenzymes NAD and FAD is to essentially carry hydrogen ions to the stage of cellular respiration called oxidative phosphorylation, I believe.
Reputake refers to the process in the brain of neurons to retrieve chemicals that were not received by the next neuron.
Because evolution itself is a very slow process. Having said that, the chance of having a continuum of various animals would mean that evolution would have progressed very fast. Because evolution is slow, different species establish themselves for different ecological niches and environments, this enables them to become better through time at a certain environment which then leads to eventual diversification in the number of species.
Perennial Shrubs I know it is late.
