Plant Growth & Development
Lesson 16
Harvesting and Threshing the Seed
This is the end of the life cycle of the students’ original Brassica plants and the beginning of new generation of plants via the seeds the students harvest.
Objectives: Students harvest and thresh the seeds. Students count the seeds and compare that number with the original number of seeds planted (8) to determine their profit or loss. Students think about additional questions they have about plants and experiments that might help answer them.
3. Lesson set up and Management
GLE 1.1.6 Understand the characteristics of living organisms.
(Lessons 1-7, 9, 10, 16)
*Identify observable characteristics of living organisms (e.g., plants have roots, stems, leaves, seeds, flowers; bees have two antennae, compound eyes, six legs, two pairs of wings, a head, thorax, and abdomen).
*Describe how plants and animals get food differently
GLE 1.2.1 Analyze how the parts of a system go together, and how these parts depend on each other.
(Lessons 1-14, 16)
*Identify the parts of a system (e.g., roots, stems, leaves, flowers, fruits, and seeds) and how the parts go together.
*Describe the function of a part of a system (e.g., leaves are the food factories of Wisconsin Fast Plants.)
*Explain how one part of a system depends upon other parts of the same system.
*Predict and explain how a system would work if one of its parts was missing or broken.
GLE 1.2.2 Understand that energy can be transformed from one object to another and can be transformed from one form of energy to another.
(Lessons3-8, 10-12, 16)
*Identify sources of energy in systems (light energy is the source of energy in a plant system; food energy is the source of energy in an animal system).
GLE 1.2.7 Understand the life cycles of plants and animals, and the differences between inherited and acquired characteristics.
(Lessons 3-12, 16)
*Observe and describe the life cycle of a plant or animal (e.g., Wisconsin Fast Plant).
*Describe that the young of plants and animals grow to resemble their parents as they mature into adults (e.g., Wisconsin Fast Plants; bees).
*Describe inherited characteristics (e.g., leaf shape, flower shape and color).
GLE 1.3.8 Understand that living things need constant energy and matter.
(Lessons 3-12, 16 and EXTENSIONS: students also earn information from listed books, videos, web sites)
*Identify sources of energy and matter used by plants and animals to grow and sustain life (e.g., air, water, light, food, mineral nutrients).
*Identify sources of energy and matter used by animals to grow and sustain life (e.g., air, water, light, food, mineral nutrients).
*Explain how plants and animals obtain food (e.g., plants make food from air, water and sunlight, mineral nutrients; animals obtain food from other living things.)
GLE 1.3.10 Understand that an organism’s ability to survive is influenced by the organism’s behavior and the ecosystem in which it lives. (EXTENSION: students learn information from listed books, videos, web sites)
*Describe the role of an organism in a food chain of an ecosystem (i.e., predator, prey, consumer, producer, decomposer, scavenger).
*Describe how an organism’s ability to survive is affected by a change in an ecosystem (e.g., the loss of one organism in a food chain affects all other organisms in that food chain.)
GLE 2.1.1 Understand how to ask a question about objects, organisms, and events in the environment.
(Lessons 1-16)
*Ask questions about objects, organisms, and events based on observations of the natural world.
GLE 2.1.2 Understand how to plan and conduct simple investigations following all safety rules.
(Lessons 1-16)
*Make predictions of the results of an investigation (e.g., growth rate of the Wisconsin Fast Plant during the growth spurt).
* Generate a logical plan for, and conduct, a simple controlled investigation with the following attributes: 1) appropriate materials, tools, and available computer technology, 2) gather, record, and organize data using appropriate units, charts, and/or graphs
*Identify and use simple equipment and tools (such as magnifiers, rulers) to gather data and extend the senses.
*Follow all safety rules during investigations.
GLE 2.1.5 Understand how to report investigations and explanations of objects, events, systems, and processes.
(Lessons 1-16)
*Report observations or data of simple investigations without making inferences.
*Summarize an investigation by describing: -materials used in the investigation, -observations, data, results, -explanations and conclusions in written, mathematical, oral, and information technology presentation formats, -safety procedures used
GLE 2.2.1 Understand that all scientific observations are reported accurately and honestly even when the observations contradict expectations.
(Lessons 1-12, 15, 16)
*Explain why scientific observations are recorded accurately and honestly.
*Explain why scientific records of observations are not changed even when the records do not match initial expectations.
*Explain why honest acknowledgement of the contributions of others and information sources are necessary.
*Describe reasons why two similar investigations can produce different results (e.g., identify possible sources of error, different rates of plant growth).
GLE 2.2.4 Understand how to make the results of scientific investigations reliable.
(Lessons 3-12, 15, 16)
*Describe how the method of investigation insures reliable results (i.e., reliability means that repeating an investigation gives similar results).
GLE 2.2.5 Understand that scientific comprehension of systems increases through inquiry.
(Lessons 3-12, 15, 16)
*Describe how scientific inquiry results in facts, unexpected findings, ideas, evidence, and explanations.
GLE 3.2.2 Understand that people have invented tools for everyday life and for scientific investigations.
(Lessons 1-12, 15, 16)
*Describe tools (technology) invented to advance scientific investigations (e.g., rulers, plant lights, automatic watering system, magnification devices, the development of Wisconsin Fast Plants by Dr. Paul Williams for classroom investigations.
- Many plants follow a life cycle that begins with growth from a seed then proceeds through the production of many new seeds.
- Plants have different stages in their life cycle.
- To live and grow, plants need light, water, carbon dioxide from the air, and mineral nutrients from the soil.
- Flowering plants must be pollinated in order to produce seeds.
- Many plants are pollinated by bees.
- A flower's pollen clings to a bee, but some rubs off when the bee feeds at other flowers.
- One seed produces one plant; one plant can produce many seeds.
3. Lesson set up and Management
STUDENT PRECONCEPTION
Some students will believe they have nothing to observe or record in their science notebooks because their plant is dead. Reinforce the concept that this is the end of the life cycle of their plant and their observations and notebook entries are just as valuable at this stage as when their plant was alive and growing.
NOTE: Make sure your students understand the big idea in science that one seed grows into one plant, and one plant produces many new seeds. This is because not every seed will grow into a new plant. Many seeds are eaten by animals, insects, and humans. Some seeds grow into plants that are eaten before they get a chance to produce new seeds. Some seeds and plants do not grow properly and die before they can reproduce because the conditions are not optimal (inadequate warmth, moisture, and/or sunlight). Many seeds have adaptations that help them travel away from the plant that produced them, giving them a better chance of finding optimal growing conditions. Mature plants that are not pollinated cannot reproduce. Therefore, to improve the chances that the life cycle of plants will continue, many seeds must be produced.
Harvesting and threshing the tiny Wisconsin Fast Plant seeds from their seed pods.
10X magnified outside view of a dried Wisconsin Fast Plant seed pod.
10X magnified inside view of a dried Wisconsin Fast Plant seed pod.
60X magnified view of Wisconsin Fast Plant seeds.
60X magnified view of the seed attachment site inside the Wisconsin Fast Plant seed pod.
FINAL ACTIVITIES
Depending on the time of year when this unit is taught, the expectations you have for writing will need to be taken into account.
Show student work from your classroom if available.
EXTENSIONS
NOTE: "The Food Chain Mystery" is a critical extension that is part of our science Grade Level Expectations and must be introduced and reinforced. The vocabulary and learning objectives are WASL-able items. Following the video, have students work in small groups to create a food energy pyramid. Make sure they label the levels as stated in learning objective #5 below and draw and label a simple food chain on their posters.
Video: "The Food Chain Mystery," running time 15 min.
Distributed by: 100% Educational Videos 1-800-483-3383
Learning Objectives (copied from video insert)
- Understand that organisms require energy.
- Know that life forms inhabit areas on the earth called habitats.
- Realize that food chains are the key to how the sun's energy is passed on to living organisms.
- Identify the difference between a food chain and a food web.
- Understand that a food chain can be thought of as a food pyramid with a large base and a small top (producers – plants, consumers – herbivores, carnivores, omnivores, decomposers – worms, bacteria, insects, microorganisms).
- Be aware that only stored energy can be passed on through the food chain.
- Realize that food chains maintain a balance within each habitat.
Explore the Wisconsin Fast Plant and the Brassica Butterfly life cycles together in your classroom:
Students will build on their knowledge and understanding of butterflies (Life Cycle of Butterflies kit – 2nd grade) as they observe the Brassica butterfly eggs hatch into larvae and quickly grow as they devour the Fast Plants (parasitic). After pupating, the butterflies will emerge, cross pollinate the Fast Plants as they consume the nectar in the flowers (symbiotic- interdependence of organisms), and lay their eggs on the Fast Plants to complete their life cycle.
To order Brassica butterfly eggs from Carolina Biological:
Order #14-4100 $10.65 Per unit of eggs
Classroom web site featuring Brassica Butterfly and Wisconsin Fast Plants:
Reading Support: Students use non-fiction reading skills.
- ScienceSaurus (use as a resource)
- How A Plant Grows
Have students partner-read and write interesting facts and questions they may have on sticky notes. Students leave their sticky notes on the pages of the book until they are ready to transfer their sticky notes into their student notebooks. Students will read this book cover to cover over the course of this science unit.