Testa

Definition

The testa is the outer protective layer of a seed. It shields the seed from physical damage and pathogens during dormancy and germination.

5 Must Know Facts For Your Next Test

1. The testa develops from the integuments of the ovule after fertilization.
2. It plays a crucial role in protecting the embryo inside the seed.
3. Testa thickness can vary significantly among different plant species.
4. It often contains compounds that can inhibit germination until conditions are favorable.
5. The testa can contribute to seed dormancy by restricting water uptake.

Review Questions

• What is the primary function of the testa in a seed?
• From which part of the ovule does the testa develop after fertilization?
• How does the thickness of the testa influence seed germination?

Related terms

endosperm: The nutrient-rich tissue formed within seeds that provides nourishment to the developing embryo.

integuments: Layers of cells surrounding the ovule that develop into the seed coat (testa) post-fertilization.

embryo: The young, developing plant contained within a seed, which will grow into a mature plant upon germination.