Answer:
Primary active transport directly uses a source of chemical energy (e.g., ATP) to move molecules across a membrane against their gradient.
The dose should be adjusted to achieve and maintain therapeutic drug levels
<span>Luca Cavalli-Sforza is a geneticist who hypothesized that the skin-color change came late because previous people had complete vitamin D access to the foods that they are eating. But the moment they started farming, the main vitamin sources are reduced, making a larger gain of having light skin.</span>
