Last updated: November 11, 2023
Lesson Plan
Flowering Plant Reproduction in the Tallgrass Prairie
- Grade Level:
- Middle School: Sixth Grade through Eighth Grade
- Subject:
- Science
- Lesson Duration:
- 90 Minutes
- Common Core Standards:
- 9-10.WHST.6, 9-10.WHST.7, 9-10.WHST.8, 11-12.WHST.1
- State Standards:
- Uses Common Core and NGSS Standards
- Additional Standards:
- Next Generation Science Standards: 4-LS1-1, MS-LS1-4, HS-LS1-2
- Thinking Skills:
- Applying: Apply an abstract idea in a concrete situation to solve a problem or relate it to a prior experience. Analyzing: Break down a concept or idea into parts and show the relationships among the parts. Creating: Bring together parts (elements, compounds) of knowledge to form a whole and build relationships for NEW situations. Evaluating: Make informed judgements about the value of ideas or materials. Use standards and criteria to support opinions and views.
Essential Question
How do plants reproduce?
Objective
How do plants reproduce? In this lesson, students explore the reproductive functions of flowers by participating in a flower dissection lab. Students will then apply their knowledge to flowering plants at the Tallgrass Prairie National Preserve or other natural area.
Background
Flowering Plant background Information.
The different parts of flowers are specialized to help plants reproduce as efficiently as possible. There is a female part of the flower, and a male part of the flower. The female part of the flower is in the center (point), and is made up of the ovary, the style, and the stigma. The stigma is sticky and captures the pollen from other flowers (sometimes carried on the legs and abdomen of pollinators such as bees, butterflies, hummingbirds etc.). The pollen germinates on the stigma and travels down the inside of the style, toward the ovary. Once the pollen reaches the ovary, it combines with the female gamete to make a seed, or ovule. The male part of the flower is the anther, stamen and filament. The anther carries the pollen, which fertilizes the female parts of the flower. The stamen and the filament hold up the anther. The petals are the colorful structures that help the flower to attract pollinators. Sepals are like petals, usually attaching below the petals on the receptacle. The receptacle is the part of the flower that is left once the flower has been fertilized, and the petals fall off. This part of the flower swells as the seeds develop. The peduncle is the junction between the receptacle and the stem of the flower.
A detailed “Pollinator Syndrome” table with many examples and information on plant/pollinator interactions from the North American Pollinator Protection Campaign can be downloaded from the lesson plan materials.
An excellent PowerPoint slide show on pollinators and their importance:
“Power of Pollinators” by Lindsay Rogers, Nebraska Game & Parks Commission Nebraska Project WILD can be downloaded from the lesson plan materials.
An interactive webpage from the United States Department of Agriculture Forest Service on pollination and pollinators: https://www.fs.usda.gov/managing-land/wildflowers/pollinators
Health and safety information for hike in a tallgrass prairie nature area.
Preparation
Gather the following materials before the lesson (one per pair):
- Dissection microscope (optional)
- Hand lens
- Computer/device with internet access
- Flowers with simple structures (lilies, tulips, irises, daisies, carnations, pansies, violets, daffodils, hibiscus, gladioli, petunias etc.). A variety for comparison is good.
- dissection pan
- Scissors
- Scalpel
- Tweezers
- Rulers
- Flower Parts Handout
- Flower drawing data sheet
- pens/pencils/colored pencils
- Reference materials: books and encyclopedias
- Copy of Classroom Activity Sheet: Flower Investigation
- List of regional native plant and animal species. This link takes you to an excellent website of Kansas wildflowers and grasses by Mike Haddock: http://www.kswildflower.org/
- Clipboards
- Field Trip Activity Sheet: Plant Pollination
If going on field trip, follow school protocol for trips and make arrangements with preserve staff, landowners etc., at the location you will be going to.
Important: Note: The field trip must be done while flowers are blooming. This will vary with location but plants go dormant during winter on the Tallgrass Prairie National Preserve. The best time to observe flowers is early fall or late spring in Kansas and may vary from year to year. Call the preserve to ask if there are flowers blooming before you finalize a date. Please educate yourself and your students on the venomous, poisonous and allergy inducing plants and animals that may be encountered on your trip and be prepared for contact (rattlesnakes, poison ivy, ticks, mosquitos, bees etc.) with them. Be prepared for any allergic reaction and bring a first aid kit. Please identify students with severe bee sting allergies and make sure there is an Epipen close by. Also note: Please call ahead and schedule a day and time for your field trip at 620-273-8494 ext. 270. Tours of the prairie and tours of the historical and cultural landmarks (ranch house, barn, and outbuildings) located at the preserve may be able to be scheduled with prior arrangement.
Lesson Hook/Preview
With a partner, have students brainstorm a list of all the flower parts they know. Have them share with the class andmake a classroom list of parts shared. Tell students that they are going to learn flower parts and their function.
Show students a diagram of a flower and discuss the locations of the parts of the plants and their functions.
The following parts should be included in this discussion: pistil, stigma, ovary, ovule, stamen, anther, petal, and sepal. Students can be given this information and be asked to research, draw, or label a blank flower diagram for further understanding.
An excellent PowerPoint slide show on pollinators and their importance:
“Power of Pollinators” by Lindsay Rogers, Nebraska Game & Parks Commission Nebraska Project WILD can be downloaded from the lesson plan materials and can also be used as a preview or hook.
Procedure
Part I – In class (Prefield trip)
Step One: have each student, or student pair, select a flower to study.
Step Two: Ask students to observe the flower with their eyes and with a magnifying glass only. Make sure each student has a copy of the Classroom Activity Sheet: Flower Investigation, on which to record observations.
Step Three: Direct them to answer the following questions on their sheets:
- How big is the flower?
- What is the shape of the flower?
- What color is the flower?
- Does the flower have an odor? Describe it.
- What flower parts, discussed earlier, can you see without dissecting it?
Once they have answered the questions,
Step Four: have students dissect the flower they chose. Students can
dissect their own flowers or in pairs so that they can share ideas and problem solve together.
Students should dissect their flower by carefully removing each part, starting from outside the flower
and working inward, counting how many of each part is present on the flower.
If a dissecting microscope is available, have students look at each part under the microscope.
Step Five: Students should record their data on the “Classroom Activity Sheet: Flower Investigation”.
You may have students include a sample of the flower part on their chart by taping or gluing it in place.
After students have identified all the flower parts, discuss the similarities they found among all the
flowers. How were the female parts of each flower similar? How were the male parts similar?
Part II – Field trip
Note: The Southwind Nature Trail at the Tallgrass Prairie National Preserve offers easy accessibility, a variety of habitats and is near the preserve visitor center but there are others from which to choose.
Step One: Using the Kansas Wildflower and Grasses website by Mike Haddock:
http://www.kswildflower.org/ , or other resources, have students pick 5 – 10 plants that will be flowering during your trip. Have students fill out Part I (hypothesis) of theField Trip Activity Sheet: Plant Pollination, for each flower. You may also assign flowers to each group to ensure that the flowers to be observed will be found on your trip. Note: if possible, hike the area or check with rangers/caretakers to ensure the flowers will be present to observe.
Step Two: Instruct students to spend 10 minutes observing a flower or group of flowers of each type that they (you) have chosen while hiking one of the trails. They should document the flower and animal (insect) types. Have them note types, numbers, and characteristics of pollinators that visit their flowers on the Field Trip Activity Sheet. Tell students to stay on the trail and to not disturb the pollinators they see. They should also note what the pollinators hang on to while feeding and if a flower was visited by more than one type of pollinator. You can also have students infer as to why a certain pollinator prefers a particular plant.
Step Three: When students are finished with the Field Trip Activity Sheet, instruct them to reflect on their time and experiences on the field trip. Have them answer the questions on the Reflection worksheet. This can be done at the park, on the bus ride home, or upon returning to the classroom.
Vocabulary
Anther – Forms pollen grains.
Filament – Supports the anther.
Ovule – Found inside the ovary and after fertilization develop into seeds.
Ovary – The lower, often times enlarged part of the pistil, which contains the egg cells and produces the seeds. The ovary becomes the fruit.
Petals – Leaf-like, often colorful part of the plant that surrounds the reproductive parts of the flower and make the flower conspicuous to pollinators. Petals collectively form the corolla.
Pistil – The female part of the flower, which is comprised of three parts – stigma, style, and ovary.
Pollen – Fine powder dust that contains the sperm from a male plant.
Pollination -Transfer of pollen from the anther of a stamen to the ovule of a flower.
Sepals – Green leaf-like structures that protect the flower bud. Collectively sepals are referred to as the calyx. Sometimes sepals are colorful like the petals.
Stamens – The male parts of the flower that produces pollen grains. Stamens consist of a filament and an anther.
Ovary – The lower, often times enlarged part of the pistil, which contains the egg cells and produces the seeds. The ovary becomes the fruit.
Stigma – Where pollen grains land on the pistil.
Style – Connects the stigma and ovary. Pollen grains travel to the ovary via the style.
Assessment Materials
How Well Do You Understand Plant Reproduction?Students should be able to diagram the parts of a flower, describe plant reproduction using correct terminology, and explain the different ways flowers can be pollinated.
Students should be able to (these may be imbedded in the procedure above):
- Label a diagram showing the parts of a flower.
- Observe and describe their flowers using appropriate language.
- Develop their own hypothesis on how pollination occurs based on observations.
- Create a detailed data chart, and verify their hypotheses based on class discussions and research.
- Compare and contrast the structure and function of the flower parts studied. Know what is similar in each flower? What varied? What functions do they have in common?
- Explain different ways flowers can be pollinated. What flowers would be best pollinated by a bee? Which would be best pollinated by the wind? Is one method of flower pollination more common among the flowers studied than another? Why?
- Compare the number of each flower part among the flowers studied.
- Discuss the benefits of animal pollination for both flowers and their animal pollinators
Supports for Struggling Learners
Partner struggling learners with those who seem to understand the content and assignment.
Enrichment Activities
Have students describe other plant/animal relationships they encountered on their field trip.
Have students describe the general relationship between pollinator and flower and describe the process of pollination in detail.
Dissect plant reproductive parts. Have students prepare thin tissue samples to study under a dissecting or compound microscope. Have them draw and label what they see making sure it include the ovules in an ovary and the pollen sacs in an anther. Ask students to estimate how many seeds the flower could produce by counting the number of ovules in the ovary.
Dissect a Fruit. After studying a number of different flowers, have students study fruits. What part of the fruit was the ovary? What part of the fruit were the ovules? Compare the fruit structure of apples, berries, and peaches (or other one-seeded fruits).
Design a Flower. Have students work in groups to design models of flowers that are pollinated various ways. Examples could include mimicking an insect to attract other insects, flowers shaped for hummingbirds, wind pollination, or colors and smell to attract insects and other animals. Have students display the designs in the classroom with small captions describing the flower’s unique characteristics.
Take-Home or in-class Activity Sheet: “Pollen Counts”. After five days, have students bring in their sheets and compare their findings. Review by asking students what they learned about pollen in their area. The sheet can be seen in the lesson plan materials.
Additional Resources
An excellent resource for identifying Kansas wildflowers and grasses: