Welcome to Our Botany Homeschool Science Course

Course Sample for Our Botany Homeschool Science Course

Botany Lesson Eight
More About Leaves and Stems

In this unit, we will:

• Learn about leaf types and structures
• Learn about stem types and structures
• Investigate how plants clean the air
• Discover plant tropisms and sensory abilities

You will need:

• Two plants and a camera
• One very ripe piece of fruit
• Two unripe pieces of fruit
• Two plastic bags

Inside a leaf

In the last unit, we talked about some of the processes that occur in the leaves and how they meet their need for air through special mouth-like openings called stoma (multiple is “stomata”). We also learned how plants move glucose, water, and minerals through capillary tubes. Now, we are going to take a look at how all these fit together in the structure of a typical leaf.

A leaf has skin, just like you. The skin is composed of a waxy cuticle and an epidermis. The waxy cuticle is secreted by the epidermis, much like your skin secretes oils, to protect it from drying out and from pathogens. It is thicker in dry climates. The stomata are in this epidermis, much like the pores of your skin. Between the upper and lower epidermis (or top and bottom of the leaf) are two layers of mesophyll, sometimes called parenchyma. The top layer of mesophyll is called the palisade mesophyll and the cells line up in columns under the upper epidermis, much like palisades. Below that is the bottom layer called spongy mesophyll and yes, it has many air pockets just like a sponge. These spaces allow gases to reach the cells and for waste gases to be expelled from the cells. All of the cells in the two mesophyll layers contain chloroplasts for photosynthesis, however, the highest concentration of chloroplasts is in the palisade layer. We will be talking about photosynthesis in more detail in the next unit. Running through the spongy mesophyll are the capillary tubes, or veins. Take a look at the drawing on the next page to see what this looks like.

To view a full sample of this class, click here.

More About Our Botany Homeschool Science Course

Take an in-depth look at plants in just a semester. Instructor Julie Polanco proves that botany is not boring. With many fun experiments and activities, Julie begins her Botany homeschool science course with a discussion of why it is important to study plants, and students are introduced to world-renowned botanists who have made important contributions to science and society such as John Bartram, Gregor Mendel, and George Washington Carver. Three weeks are spent examining soil and the minerals contained within it. The function of roots, leaves, and stems, as well as plant respiration and circulation, are discussed. Middle school and high school homeschool students will learn about the importance of light and the process of photosynthesis. They will also learn how to tell the difference between deciduous trees and gymnosperms, find out how plants know when to get ready for winter, and why some trees don’t lose their leaves. A few weeks are spent exploring plant defenses, plants as medicine, and flowers as food. Teens learn why God designed plants the way He did and what role they play in our world.

Since the lessons in this Botany homeschool science course build on one another, it is best to start with lesson one and move through sequentially, as best fits the homeschool student’s schedule. While the lessons and forms needed are all printable from the site, some experiments require basic household supplies and parental oversight to complete. The student should keep a notebook containing all worksheets and experiments. While some activities are listed as optional, this is to allow for middle school flexibility. High school homeschool students should be completing all activities and experiments. In addition to the online text material offered each week, it can take up to two hours for the student to complete the worksheet and any activities and experiments.  

Many worksheets have answer keys. For those sheets that do not, it is because the answers will vary and parents should check whether the teen has completed the assignment. For example, one lesson asks the student to do some research on carnivorous traps and how they work. Please make sure that the student wrote about a trap, answered the questions posed, and gave enough information. Usually, the worksheet specifies how long the paragraph or mini-essay needs to be.

Two tests are offered, one at Week Nine and one at Week Seventeen, and these are separate from the week’s lesson material. Please plan accordingly. These are essay tests and have answer keys. Specific grading scales are left to the discretion of the homeschool parent. As always, please check your own state’s academic requirements.