NEET UG BIOLOGY MCQ: ANIMAL KINGDOM

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Understanding +4 | -1

[A]: When a foreign object, such as a sand grain gets in between the shell and mantle, it results in the formation of a pearl.

[R]: The inner nacreous layer of irridiscent nacre is called the mother of pearl which is formed of many thin and alternating layers of calcium carbonate and concholin.

View answer and explanation

Correct option: A

Both A and R are true and R is the correct explanation of A

Option A is correct because both the assertion and reason are true, and the reason correctly explains how pearls are formed when a foreign object is coated with nacre.

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