oysters take in a grain of sand they open up with a pearl. use---ing participle and rewrite
Answers
A grain of sand is not the usual culprit that spurs the creation of a pearl. It is more of a myth than anything. At the center of a natural pearl the irritant is probably a parasite (example would be a tiny worm larvae). So, perhaps one thing we can learn is that research and critical thinking are important, even before posing questions.
It is formed when irritants become lodged in the soft tissue inside an oyster's shell, and, to protect itself, the oyster produces a coating for the irritant. This coating, called nacre, builds up in many thin layers and creates an iridescent cover over the irritant. The resulting product is a pearl. Just a different oddity in nature.
It did teach people how to culture pearls using irritant that is surgically implanted in an oyster as the nucleus of the pearl is made from the shell of a mussel.