In this 7th grade science lesson, students review the structures and processes that allow flowering plants to reproduce, and then pick a flower from the garden to dissect and diagram.
After this lesson, students will be able to:
- Name the structures of a flower and identify their respective functions
During this lesson, students will:
- Complete the Biology of a Flower worksheet, dissect a flower, and draw and label the parts of a flower
- Biology of a Flower worksheet
- Blank paper
- Pollen images (National Geographic has good examples)
- Fresh flowers for dissection (good examples are Nasturtium, because it is great for showing a landing strip, Digitalis, because it is fuzzy and therefore catches pollen well, and Columbine, because it is great for observing ovules)
Before You Begin
- Copy the Biology of a Flower worksheet to hand out
- Ensure there are enough flowering plants in the garden
At the Opening Circle
- Welcome students and introduce this Biology of a Flower lesson as an opportunity for them to learn how flowering plants reproduce by studying real flowers.
- Divide students into working groups. Offer this lesson as one of the garden jobs for today's class, and continue to offer it until all students have completed this lesson. At the Edible Schoolyard Berkeley, it takes three classes.
In the Field
1. Pass out a clipboard, pencil, and Biology of a Flower worksheet to each student.
2. Explain to students that most flowers have both male and female organs.
3. Beginning with the Pistil, complete the biology of a flower worksheet with students.
4. Share pictures of magnified flowers with pollen and review pollen’s role in reproduction.
5. Show a magnification of pollen and discuss how types of pollen can be traced back to the types of flower from which they came.
6. Ask students to imagine they are all bees and ask students to use the vocabulary just learned to answer the following questions:
a. What part of the flower are you first attracted to? (Petals)
b. As you drink nectar, what rubs on to your body and gets stuck on your legs and belly (Pollen)
c. Then, when you move on to another flower, what sticky surface traps the pollen from your legs and belly? (Stigma)
d. From the stigma, what tube does the pollen travel down? (Style)
e. After pollen travels down the style, what does the pollen fertilize? (Ovary)
f. What does the ovary turn into once fertilized? (Fruit)
g. Who eats fruit? (humans, animals)
7. Now that students know the parts and functions of flowers, have students walk through the garden and pick flowers they would like to dissect, draw, and label.
8. Have students draw and label their flowers independently. Encourage them to draw their flowers from different perspectives and at different stages of dissection.
At the Closing Circle
Collect worksheets and drawings from students and hand them in to their classroom teacher.