Lesson 8 of Apologia's Exploring Creation with Botany is all about "Stems."
We use the Junior Botany Notebooking Journal with every lesson, to record what we learn and the fun projects we do together. I know some people opt to not buy the journals, but I highly recommend them. This is our third journal (for our third Apologia science course) and each one serves as a special book of memories of all the fun we have together. It's not a workbook. It's a scrapbook.
To start this lesson, we read pages 117-120 from our text, learning about different stems (both woody and herbaceous), vascular bundles of xylem and phloem in stems, the role of the vascular cambium in stems, and the fact that cacti have no leaves -- what you see are their stems! Fascinating!
We then read about the largest cactus in the world out of our Usborne Starting Point Science book (Volume 1, page 44), the saguaro. It grows as high as 50 feet and lives for over 200 years!
From there, we did some work in Evan-Moor's Giant Science Resource Book.
We completed two worksheets. The first was this "Parts of a Plant" sheet which required her to label the parts of different plants (page 14).
The second was this one, entitled, "Plants We Eat." Looking at each item, she had to determine which part of the plant goes on our plates!
After reading about how xylem is responsible for moving water up a plant's stem from the roots, Maggie demonstrated this action with her straw.
We then got to work to see xylem in action with the suggested celery activity from the text (page 123). Maggie decided she wanted to experiment with both red ...
... and blue!
We placed our stems in the water and waited.
After a couple of days, we noticed how hard that xylem had been working!
We had red and blue leaves!
With the added color, the xylem tubes were now easy to spot on the underside of the celery stalks!
We decided to experiment some more with xylem, this time with more colors (with green and yellow added), and with a different kind of stem, with white carnations.
Going into their baths, the blossoms were stark white.
In three days, though it's hard to see, each blossom had a tinge of the color it had sat in. (Blue showed up the best.)
Here, we have blue ...
... green ...
... yellow ...
... and red.
(It was actually easier to see some of the color on the underside of the petals.)
The white rose we stuck in blue actually picked up the color much better than the carnation in blue did. So I would suggest trying this activity with white roses instead of white carnations.
All of our experiments (notes and photos) go into our journal.
We did yet another experiment with some of our extra carnations that we found in our 501 Science Experiments book ("Stem-less Flowers," #115). This experiment demonstrates how helpful a stem is to a flower.
We started out with two flowers of equal size and health (by appearance).
Then, we chopped the stem off of one.
Here they are, one "Stem-less." We kept both out of water and just laid them on the counter for observation.
After two days, we could see a real difference! The one with the stem (right) still looked great, even out of water all this time. The one without the stem (left) had reduced in size significantly, and appeared much more wilted. Interesting! Even without water, stems provide for plants!
We continued recording.
Maggie has been wanting to try to grow and keep a cactus, so this was a great lesson to do that! I purchased both a ""Carol Cactus" plant kit (by Eco Plant Pals) ...
... and an "Aloe Alin" plant kit (also by Eco Plant Pals) from Hobby Lobby for us to put together.
She was so excited! We put them together and they now soak up sun on her desk.
(*As of the date this post was published, both have small sprouts!)
After all of our stem experiments were set up, we continued reading in our text about auxins and phototropism.
We then completed the "Phototropism Activity" outlined on page 122 of the text. Using clay, we shaped a thick "stem." Then, we pinched one side of it to represent the "dark side" of the stem. This simulated what auxins do in a real stem. As we pinched to your right, the side of the stem that was facing the light (the left), bent towards the light. Neat!
We continued to journal all that we were learning.
We read about some interesting stems in our Usborne Mysteries & Marvels of Nature book ("Plants on the Move" (with images of phototropism), pages 18-19, "Plants Fight Back" (stem defenses), page 31, and "A Tough Life" (plants exposed to extreme temperatures), pages 102-103).
We looked at another stem defense (thorns) in our Plant Adaptations science photo cards pack. (I have loved using these because every photo card comes with lots of information about what is pictured.)
Here is the photo card we looked at for this lesson from that pack.
We then decided it was time to look at some stems up close. We have three stem slides in our microscope slides collection ("Stem of Cotton," "Stem of Wood Dicotyledon," and "Stem of Corn"). We looked at all three.
What we noticed about all of them was the many tube openings (those vascular bundles of xylem and phloem) in each. Those stems do important work!
Next, we completed the "Twisted Branches" activity outlined on page 123 of the text. (This we recorded on page 139 of our journal.)
For a final experiment for our study of stems (specifically, phototropism), we purchased this Grow-A-Maze kit by Green Science. (I got it on the clearance rack at Hobby Lobby for $6.59.) With it, we would plant some seeds and watch their shoots navigate through the maze we created to reach the light at the top. We were excited to get started!
We decided to pick some of the seeds we knew to sprout quicker than most -- bean seeds! Here are our seeds in the window, laying with moist paper towels to encourage them.
Within a few days, we had victory!
We followed the instructions in the kit to set the seeds up and will wait a bit longer for the shoots to grow before attaching the maze top. (We will update this post when they do!)
We finished up our notebooking work and called it another great lesson!
Lesson 9 of this text, "Trees," is already in mid-study at our house. After this week, we only have three more lessons left in this course. Maggie is already mourning the end to our Botany studies. It has been fantastic. Check back with us for Lesson 9!