The hard or gritty parts of fruits and vegetables are made up of sclerenchyma cells.

Here's why:

* Sclerenchyma are a type of plant cell that have thick, rigid cell walls made of lignin. This gives them their strength and rigidity.

* Examples: You'll find sclerenchyma in the gritty texture of pears, the hard seeds of fruits like watermelon and avocado, and the tough fibers of celery stalks.

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