From Seed to Seed:
Plant Science for K-8 Educators

Stages of Germination

We have already learned that seeds contain embryonic roots, stems, and leaves, and enough food to keep the plant growing until it has the ability to produce its own food through photosynthesis.

Epicotyl (will become the shoot-stems and leaves) Radicle (embryonic root) Hypocotyl (connection between cotyledon and radicle) Cotyledon (seed leaf) Note: If the seed has one cotyledon, it is a monocot. Corn is a monocot. If it has two, it is a dicot. A bean is a dicot.

Once germination requirements have been met, these embryonic plant parts begin to grow. Botanists are still debating whether cell expansion or cell division is responsible for this growth. Either way, the following process takes place:

1) The radicle pushes through the seed coat into the soil

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2) Primary roots begin to develop and the hypocotyl forms a hook that straightens out, pulling the cotyledons above ground.

3) The emergent seedling begin to straighten out, taking the cotyledons with it.

4) The primary leaves begin unfolding and the stem elongates.

5) The true leaves completely emerge and the cotyledons eventually fall off.

Once the true leaves have completely emerged, the germination process is complete.

Plants are able to carry out all of their activities, including germination, because cells perform their designated tasks. Let's get reacquainted with cells before we really dive into what plants do.

Relevant Books
K-4
Kellogg, Steven. 1997. Jack and the Beanstalk. Mulberry Books. ISBN: 0-6881-5281-3.

Carle, Eric. 1987. The Tiny Seed. Simon & Schuster. ISBN: 0-8870-8015-4.

Gibbons, Gail. 1993. From Seed to Plant. Holiday House. ISBN: 0-8234-1025-0.

5-8
Ayers, Patricia. 2000. A Kid's Guide to How Flowers Grow. Powerkids Press. ISBN: 0-8239- 5462-5.

Pascoe, Elaine. 1997. Nature Close-Up: Seeds and Seedlings. Blackbirch Marketing. ISBN: 1-5671-1178-5.