You only need the English Proficient for international operations as it's an ICAO thing. Some countries, like France, check; others may not. Similar on the RRTO -- some countries, like Canada and the Bahamas don't require it, but others, like Turks & Caicos, do require it and do check it.
Apoptosis, or programmed cell death, is a naturally occurring process in the body. It involves a controlled sequence of steps in which cells signal self termination. Apoptosis works to keep the body's natural cell division process of mitosis in check.
When a death signal is received by the cell, it overrides the brake, and the apoptotic pathway activates proteases and nucleases, enzymes that cut up the protein and DNA of the cell. The main proteases of apoptosis are called caspases; in the nematode, the chief caspase is Ced-3.