How exactly do oysters make a pearl out of a tiny grane of sand?

Question

And do clams or any other sea creature make pearls?

Answer 1

They don't make the pearl out of th egrain of sand, exactly. What happens is this: a grain of sand--or some other smallparticle of foreign matter--occasionaly works its way into the oysters shell and becomes trapped.

for the oyster, this is irritating--and possibly harmful, since the foreign matter could create an infection or abcess. The oyster's defense is to secrete a fluid that hardens around the particle. However, this trait has a drawback (for the oyster). The particle--now covered in a smoth shell of the hardend secretion (called mother-of pearl, BTW) is still there. So the oyster keeps secreting layer after layer--and the pearl thus formed keeps getting bigger and bigger.

Answer 2

A pearl is the result of the oyster's natural defense against a foreign substance in its body. Once a grain of sand or some other irritant finds its way inside the oysters body starts to coat it in nacre, the same calcareous substance its shell is made of. Over time it becomes a pearl. They don't always turn out to be round, when they are in odd shapes they are referred to as baroque pearls. They also come in a variety of colors depending on what species of oyster it is and what part of the world its in.

Mussels and clams can also make pearls but it is a much rarer occurrence.

Answer 3

Oysters are mollusks. They have very soft bodies enclosed in a two-piece shell (bi-valve). They are filter feeders which means they get their food by "sucking in" sea water. Oysters bury themselves in the sand on the bottom of the bay (this is a protective behavior) and stick their siphons up to collect the sea water which has minute particles of nutrients in it. Sometimes sand gets sucked up, too.

When sand gets inside the oyster shell it becomes an irritant. The oyster protects itself by secreting a substance called nacre (the white, pearly-looking stuff that lines the inside of the oyster shell) which coats the sand particle. Eventually the nacre covers the sand particle enough that it no longer is irritating to the oyster. This nacre-covered sand particle is what we call a pearl

Answer 4

Once a grain of sand enters the oyster it irritates the inside. The natural defense for this is the oyster secretes calcium carobonate. As this builds up for a period of time the end result is a pearl.

Answer 5

Oysters and clams do not make pearls from grains of sand; the sand irritates the little animal inside the shell, so in order to relieve its pain, it excretes a substance which eventually evolves and hardens into the pearl.

Answer 6

The oyster treats the grain of sand as an intruder that might do it harm. It secretes a substance to surround the sand with a protective coating. Perhaps the oyster cannot know when the job is done, but keeps adding to the coating.

Answer 7

How do oysters make pearls Answer

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