Seed Germination

A seed is an embryonic plant that is enclosed in a seed coat or some kind of protection (Seed, 2009). A seed is the basis for any plant life; it is the essential beginning for any sort of growth. A seed is created from a previous plant or two plants pollinating with each other to create a seedling (Seed, 2009).

Typically there are three main parts of a seed: an embryo, nutrients for the embryo, and a seed coat (Seed, 2009). The embryo is the true essential of the seed. It contains the one cotyledon, or plant leaf, which under the right conditions will spark the initial seed germination (Seed, 2009). The nutrients for the embryo surround it. These nutrients are stored in endosperm. Endosperm has a heavier concentration in oil, starch, and proteins (Seed, 2009). These nutrients are used through the seeds dormancy to survive. By the seeds full maturity these nutrients have mostly been used up. The seed coat is protection for the seed to ensure the seen will be protected from any kind of damage.

The adaptive value of a seed all depends on the location of the plant and previous mutations of that species (Koning, 1994). For example some seed can go for extended periods of time with out water, or some seeds only open to extreme temperatures like a bitter freeze or a wild fire. These seed are adapted like this for maximum reproduction and for the best survival.

Germination is the process when a seed emerges from its dormancy (Seed Germination, 2009). The most common example of seed germination is the sprouting of a seed in its transition to seedling.

The three main factors for seed germination to occur are water, oxygen, and temperature (Seed Germination, 2009). Water amount is extremely important in that seed are usually exceptionally dry. The seed needs water to emerge and germinate, but contrary to that if a seed is drowned in water then it will absorb too much or be suffocated. Seeds also need oxygen to successfully germinate, but polluted oxygen can be harmful, such as if the air contained too much CO2 or some sort of harmful airborne chemical. Temperature affects the cellular metabolism or simply put, growth rate. Too low of a temperature can cause the seed to shut down and die, but too high of a temperature can cause the seed to cook and that will in turn also cause the seed to die.

Other factors that can affect seed germination are light exposure (Seed Germination, 2009), soil ph (Seed Germination, 2009), and the depth of the seed (Koning, 1994). Some seeds need direct sunlight to trigger germination due to their chances of survival. Such as some plants in a forest will not germinate until there is an opening in the canopy, due to that if it were to germinate when there is no direct sunlight there would be little chance for photosynthesis. Or if the sunlight is too intense then the seed could possibly die. The ph of soil surrounding a seed can cause harm to a seeds development. Such as if the ph was to acidic the seed coating might fail thus causing the seed to die. Another secondary factor of seed germination is the depth of the seed. If a seed is too deep then it may not receive enough water, oxygen, or the desired temperature. If the seed is too shallow then it may be disturbed or eaten by a scavenger.