Seeds

I learned there are 6 parts to a seed. The first part is called the testa and it's the covering of the seed. Testas aren't the same color or size in every plant. If you want to grow a seed, it has to have warmth, air, and water. It doesn't need soil because it will get its nutrition from the second of the part of the seed which are the cotyledans. These are the round and the largest part of the seed. The are the food for the seed until it sprouts and gets big enough to grow on its own.

The three other parts of the seed are the radicle (which becomes the root), the hypotyl (which becomes the stem), and the epicotyl (which becomes the top of the plant and holds the leaves).

When there are baby leaves in a seed, they are called plumules. It is not common to have plumules in a seed, about as common as a baby born with teeth. Bean seeds have plumules and that includes peanuts.

There is a special word for when a seed sprouts. It is called germination. The seeds doesn't need sunlight yet, either, when it germinates. One of the first things a seed will do is to grow a stem, the hypocotyl, because it's trying to reach for light. If it is dark, the stem will grow longer and longer because its trying to survive. It knows it will need sunlight to survive.

We planted some herb seeds and put a box over them with a light that shines day and night. The first seeds lavender and oregano seeds sprouted today, about a week later.
You can see them in the photo below.

Ferns Have Spores

Today we learned about Pterophyta phylum. Pterophyta means winged plant. Think of a pterodactyl which is a dinosaur with wings. These plants have leaves which look like wings or feathers. These are different from other plants we've studied because they have spores instead of seeds.

Spores have a baby plant in a container but they are different from a seed because they don't have any food for the baby plant. That makes them very small, much smaller than a seed. I learned that a seed is a container with food AND a baby plant inside of it.

You find spores under the leaves of ferns. Leaves on ferns are called fronds.

There aren't any ferns around our house but we went to a close-by plant store called a nursery to see ferns. Here are some photos we took of our visit:


Ferns grow in a circle like this one.























Here you can see the spores under the leaves around the edges.

Uncovered Seeds

Uncovered seeds are called gymnosperms. There are four groups of gymnosperms but coniferphytas have the most. Coniferphyta means cone bearer plants.I learned that pine trees have uncovered seeds and they are gymnosperms.

We have five big pine trees close to our house. They are green even in the winter because they are evergreens. When we walked to the trees, we picked up pine cones by the trees. They were old ones which we could tell by looking at them closely. They were brown and rotting. We saw some little new cones on the trees on the tips of the branches.



You can see tiny pine cones on the tips of the branches if you look closely.






Here are Philip and Peter standing by a Christmas tree someone planted years ago.


There were plenty of cones still up in this tree.

Seed Containers

I learned that another way to classify plants is if they have seeds or don't have seeds. If they make seeds, they are called angiosperms or gymnosperms. Gymnosperms have pinecones. Sperms means seed. Angio means container. Angiosperms have seed containers. First, we will study angiosperms.

Some examples of seed containers are fruit, nuts and flowers. How a seed container gets created is by a flower. When all the nectar is sucked out of a flower, the petals dry up and fall off. Then, it starts to get fat and turns into something like an apple or a walnut.

Here are some angiosperms we found around our house.

This is a rosemary flower.



This is a flower from the trumpet vine near our front door. The top is a flower, the next you see the petals drying up. Then on the bottom, you see the seed pod forming. All of these are happening at the same time!


A samara seed has a wing so it flys and comes off trees.


Peter drew this picture of some angiosperms.

Mosses

Today I learned that moss is in the plant kingdom and that it doesn't have any tubes. That is called nonvascular.

I think I found some moss in our backyard on the bottom of the porch cement by the grass. There was some moss in the grass, too. Moss gets water by absorbing water like a paper towel. If it dries out, it dies. We live in Tucson so moss is hard to find because it's dry and there's no water that stays around.

The grasses is always moist so that's why we found moss there.

This is a photo of some moss growing on the ground in a greenhouse near us. This place is always moist: Perfect for moss.