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.
Phagocytosis is an effective nonspecific immune response. Phagocytosis recognizes alien cells and particles. For the phagocytosis to proceed, macrophages and neutrophils must first recognize the surface of a particle as foreign. When a phagocyte surface interacts with the surface of another body cell, the phagocyte becomes temporarily paralyzed.