The female reproductive organ of a plant that produces egg cells is called the ovary.

Here's a breakdown:

* Ovary: This is the swollen base of the pistil, the female reproductive part of a flower. Inside the ovary are one or more ovules, which contain the egg cells (also called gametes).

* Ovule: Each ovule contains a single egg cell, which is the female gamete.

* Egg cell: This is the haploid cell that, when fertilized by a sperm cell, will develop into a seed.

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