Which part of a seed grows into a root and which plant part acts as a protective covering for a seed during seed dormancy? the part of a seed grows into a root and the acts as a protective covering for a seed during seed dormancy.

The part of a seed grows into a root: Radicle

The part that acts as a protective covering for a seed during seed dormancy: Seed coat.

Explanation:

The seed of the plants carries embryo in it. The part of the embryo that serves as the embryonic root is called radicle. Once the conditions become favorable for growth and the seed germinates on suitable substratum, the radicle enlarges and gives rise to roots.  

The seed coat is the part of the seed that protects the embryo from any injury during the seed dormancy. The seed coat is derived from the outer most covering, that is integuments of the ovule after fertilization.

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