Our First Born! Table 5's Baby Book

{Seed Structure, Function, and Germination Explained}

Our little boy! Look at that adorable embryo!

I can’t believe it, we’re expecting! 

We found seeds the other day and we’re going to plant them soon. It’s weird picturing a mini plant inside the seed coat, but trust me, it’s there. The plant embryo has a root, called the radicle, and leaves, called cotyledons. This seed is a dicot, we assume, which means that its two cotyledons take up most of the space inside the seed coat and have absorbed most of the endosperm, a triploid tissue containing nutrients for the embryo to survive until it can start making its own food If it were a monocot, the single cotyledon is called a coleoptile, and there is more endosperm left over inside the seed coat. The cotyledons are there to start photosynthesis until true leaves start to form. I’m tearing up just thinking about it! Good thing they haven’t even germinated yet. 

I think they've already started to germinate. It was literally yesterday that they were still dormant seeds. Seeds can stay dormant for a really long time. Germination doesn't happen until conditions optimal for the seed are met such as water in the soil, presence of light, or temperature. This is so that the plant can fix itself (forever) in a spot where it has a good chance of surviving. Some seeds have such tough seed coats that they need scarification, or the abrasion of the seed coat, before they will germinate. This is sometimes achieved by passing through the digestive tract of an animal who ate fruit. Ick! The seed absorbs water and the seed coat breaks, allowing the radicle to emerge and start taking up more water. Metabolism of the endosperm sugars begins as the seed starts to grow. I can't wait until the hypocotyl emerges!