Seed Germination Questions?

The emerging shoot or radicle.

For most seeds the radicle emerge because it is needed to establish the new seedling in the soil, it anchors the germinating seed and draws water into the seedling.

The shoot, with in the seed it is called the plumule.  The embroy has two growing points the plumule, which becomes the stem with leaves and the radical which becomes the first root.

Seeds derive their nutrients from the seed until green leaves are fully expanded.  Seeds store nutrients in different structures depending on the species, but many have endosperm.