Outside of the U.S., many cruise lines do not have automatic tipping policies, says McDaniel, as other countriesâ tipping customs are different than ours (and thus their staff is paid differently), so it may pay to look at cruises leaving from other countries and then look at their âsuggestedâ tipping options.
Best Answer: Active transport is the mediated process of moving particles across a biological membrane against a concentration gradient. If the process uses chemical energy, such as from adenosine triphosphate (ATP), it is termed primary active transport. Secondary active transport involves the use of an electrochemical gradient.
Examples of Active Transport. Transport that is âactiveâ is different in that it requires the energy of certain membrane proteins to get across the concentration gradient and either into or out of the cell. It requires more from the cell and it usually costs something in terms of energy and nutrient expenditure, too.