The next stage of germination is the interim or lag phase. In this stage, the seed initiates its internal processes, including cellular respiration, protein synthesis, and metabolization of food stores within the cell. (Seed and Seedling Biology, n.d.). Finally, the seed enters the third stage of germination, radicle and root emergence. In this stage, cells within the seed begin to elongate and divide, pushing the root and radicle out of the seed (Seed and Seedling Biology, n.d.).

After the process of germination, early seedling development begins. In dicots, or two-seed leaves, such as Phaseolus vulgaris, t he radicle attaches the plant to the ground and begins to absorb water from the substrate (Seed and Seedling Biology, n.d.). After this, the shoot emerges from the seed. The shoot is made up of 3 parts, the cotyledons, or seed leaves, the

hypocotyl, which is the section of shoot below the cotyledons, and the epicotyl, which is the section of shoot above the cotyledons (Seed and Seedling Biology, n.d.). In species of beans such as Phaseolus vulgaris, t he seed undergoes epigeal germination, in which the hypocotyl forms a hook which pulls the cotyledons and epicotyl to the surface of the soil. After this, the hypocotyl straightens, pulling the rest of the shoot into the air (Seed and Seedling Biology, n.d.).

(Seed Germination, n.d.)

In my investigation, I will be exploring the effect of vermiculite concentration within the substrate as it relates to seed germination, seedling growth, and survival. Vermiculite is a natural compound of the chemical formula (Mg,Fe++,Al)3(Al,Si)4O10(OH)2•4(H2O), and is mined across the United States and the rest of the world (Barthelmy, n.d.) Horticultural vermiculite is commonly used in agriculture, as it improves soil aeration while retaining necessary moisture and nutrients for plant growth (Horticultural Uses, n.d.). Vermiculite is particularly effective in seed germination, as it increases the availability of oxygen and water, two necessary components