Germination

Whether it is a bean seed or a corn seed germination requires a few things. It requires water/imbibition, oxygen, temperature/sunlight, soil and a nice, loving parent:)

Germination: the sprouting of the seed. The seed swells from intake of water, and the outer coat begins to soften. After the coat breaks, the radicle appears and grows downward due to gravity.

Water/Imbibition: Water is required for germination. Water allows the outer shell of the seed to soften and break for the seed to take root and grow. This process is called imbibition. Mature seeds are often extremely dry and need to take in significant amounts of water.

Oxygen: is required by the germinating seed for metabolism. Oxygen is used in aerobic respiration, the main source of the seedling's energy until it grows leaves.

Temperature/Sunlight: affects growth rates. Seeds from different species and even seeds from the same plant germinate over a wide range of temperatures. If it is too cold it will freeze, and if it is too hot it will whither. Also with sunlight, some seeds germinate better without sunlight and some germinate better with sunlight. The perfect temperature and the perfect lighting is definitely very important for germination.

Soil: The pH of the soil can make a  difference in the germinating seed.The pH of the soil helps with the softening of the outter shell so the root can grow.

Two factors that need to be taken into consideration when expecting a seed to germinate:

Dormancy period: A seed requires to undergo a period of dormancy after its formation. During this period the seed 'rests' and may refuse to germinate properly. This period varies from seed to seed.

Viability period: After the resting period a seed bcomes ready to germinate. But this readiness is not for ever. The seed can possibly "expire" after a certain period. After that, the seed will not germinate.

Seed Structure and Function

Lets start off by showing off the structure and function of my cute babies Layla(corn) and Tommy(bean).

 

Corn(Layla): The endosperm of a monocot corn seed stores the food, which in this instance it is starch.The cotyledon of the corn seed is located above the embryo and it digests the food from the endosperm and feeds it to the develpoing embryo which is at the bottom peak of the seed and is the actual seed before germination.The codyledon will eventually become the leaves of the developed plant. The epicotyl, hypocotyl, and the radicle are all within the embryo. The Epicotyl is the stem above the cotyledon and will become the stem and leaves. The hypocotyl will develope into the lower stem under the cotyledon. And the radicle will become the root of the developing plant.

Bean(Tommy): The endosperm or cotyledon of a dicot bean seed stores the food, which in this instance it is starch, just like the corn seed.The cotyledon of the bean seed is located twice, unlike the corn seed. It is pretty much located all around the inside of the seed and does the job of both the cotyledon and the endosperm. The codyledon will eventually become the leaves of the developed plant. The embryo is near the top and is the seed before it is developed.The epicotyl, hypocotyl, and the radicle are all within the embryo. The Epicotyl is the stem above the cotyledon and will become the stem and leaves. The hypocotyl will develope into the lower stem under the cotyledon. And the radicle will become the root of the developing plant.