AP BIOLOGY

Detailed explanation-1: -The primary root, or radicle, is the first organ to appear when a seed germinates. It grows downward into the soil, anchoring the seedling. In gymnosperms and dicotyledons (angiosperms with two seed leaves), the radicle becomes a taproot.

Detailed explanation-2: -Radicle is the first part of a seedling to emerge from the seed during the process of germination. It is the embryonic root of the plant and grows downward into the soil.

Detailed explanation-3: -The radicle (primary embryonic root) emerges from the seed first to enhance water uptake; it is protected by a root cap produced by the root apical meristem. Water is essential for metabolic activity, but so is oxygen. A seed sitting in a glass of water will not survive.

Detailed explanation-4: -The radicle is the first part of a seedling (a growing plant embryo) to emerge from the seed during the process of germination. The radicle is the embryonic root of the plant, and grows downward in the soil (the shoot emerges from the plumule).

Detailed explanation-5: -The radicle grows first because the roots need to stabilise the plant before the leaves and stem grow, and the roots gather water and nutrients from the soil which are needed to continue growing.