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.
Programmed cell death is called apoptosis, and when this process breaks down, cancer begins to form. Unlike regular cells, cancer cells do not experience programmatic death and instead continue to grow and divide. This leads to a mass of abnormal cells that grows out of control. What is cancer? - Video. A short, 3D, animated introduction to cancer.