primary root

American  

noun

Botany.

1. the first root produced by a germinating seed, developing from the radicle of the embryo.

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primary root Scientific  

1. The first root of a plant, originating in the embryo. In gymnosperms, eudicotyledons, and magnoliids, the primary root develops into the taproot. In monocotyledons, the primary root disintegrates as the lateral roots develop into a system of fibrous roots.

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Etymology

Origin of primary root

First recorded in 1885–90

Example Sentences

That the primary root of all educational activity is in the instinctive, impulsive attitudes and activities of the child, and not in the presentation and application of external material.

From The History of Education; educational practice and progress considered as a phase of the development and spread of western civilization by Cubberley, Ellwood Patterson

The growth of the primary root is limited; sooner or later adventitious roots develop from the axis above the radicle which they ultimately exceed in growth.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 3 "Gordon, Lord George" to "Grasses" by Various

In many Dicotyledons and most Monocotyledons, the primary root soon perishes, and its place is taken by adventitious roots developed from the stem.

From Encyclopaedia Britannica, 11th Edition, Volume 2, Part 1, Slice 1 by Various

The primary root of the embryo in all Angiosperms points towards the micropyle.

From Encyclopaedia Britannica, 11th Edition, Volume 2, Part 1, Slice 1 by Various

The single root of the commoner biennials is the primary root, or tap-root, which begins to thicken in the seedling.

From The Elements of Botany For Beginners and For Schools by Gray, Asa