In cultured pearls, a mother-of-pearl bead or a piece of tissue is inserted (by man) into the mollusk to start the process. For both, the quality of the nacre dictates the quality of the luster, or shine of the pearl, which is very important to its beauty and its value.
For an airplane pilot, education takes many forms, including applied instruction, a high school diploma, an associate's or bachelor's degree, and specialized training. The Federal Aviation Administration also requires pilots to accumulate a lot of real-world knowledge in the form of flight-hours.
As a commercial airline pilot, you will be subject to these examinations throughout your career; captains need to pass a physical exam once every six months, and other commercial airline pilots need to pass an exam every year. If a health problem is discovered, you could be out of a job.