Dressed for Success: How Do Specialized Plant Structures Increase the Probability of Successful Reproduction?

Learning Resource Type

Lesson Plan

Subject Area

Science

Grade(s)

Overview

At the beginning of the lesson, students will view an engaging video of time-lapse photographs of flowers blooming, and students will create a T-chart listing the similarities and differences among the appearances of each flower. To formatively assess students' current knowledge of specialized plant structures, the students will sort key vocabulary words related to plants' structures into categories. Then, students will read an informational article on flowering plants and re-sort the key vocabulary words into the correct categories to demonstrate their knowledge of plants' specialized reproductive structures. Next, students will complete a lab activity in which they will carefully dissect a flower and observe the various specialized structures, collect specimens to view under the microscope and create and label scientific sketches of the flower's specialized structures. Lastly, students will design a unique flower that will have a high probability of reproductive success and provide a written response in a claim-evidence-reasoning format.

This lesson results from a collaboration between the Alabama State Department of Education and ASTA.

Science (2015) Grade(s): 7

SC15.7.10
Use evidence and scientific reasoning to explain how characteristic animal behaviors (e.g., building nests to protect young from cold, herding to protect young from predators, attracting mates for breeding by producing special sounds and displaying colorful plumage, transferring pollen or seeds to create conditions for seed germination and growth) and specialized plant structures (e.g., flower brightness, nectar, and odor attracting birds that transfer pollen; hard outer shells on seeds providing protection prior to germination) affect the probability of successful reproduction of both animals and plants.

Vocabulary

Evidence
Cause and effect
Scientific Reasoning
Characteristics
Behaviors
Specialization
Probability
Reproduction
Validity
Reliability
Relevance

Knowledge

Students know:

Animals engage in characteristic behaviors that increase the odds of reproduction.
Plants reproduce in a variety of ways, sometimes depending on animal behavior and specialized features for reproduction.

Skills

Students are able to:

Make a claim to support a given explanation of a phenomenon, including the idea that characteristic animal behaviors and specialized plant structures affect the probability of successful reproduction of animals and plants respectively.
dentify the given evidence that supports the claim (e.g., evidence from data and scientific literature).
Evaluate the evidence and identify the strengths and weaknesses of the evidence used to support the claim.
Use reasoning to connect the appropriate evidence to the claim, using oral or written arguments.

Understanding

Students understand that:

Many characteristics and behaviors of animals and plants increase the likelihood of successful reproduction.
Animal behavior plays a role in the likelihood of successful reproduction in plants.
Because successful reproduction has several causes and contributing factors, the cause and effect relationships between any of these characteristics and reproductive likelihood can be accurately reflected only in terms of probability.

Scientific and Engineering Practices

Constructing Explanations and Designing Solutions

Crosscutting Concepts

Cause and Effect

Primary Learning Objectives

Students will identify and describe the specialized plant structures that affect the probability of the successful reproduction of plants.
Students will provide evidence and use scientific reasoning to explain how a plant's specialized structures would positively impact its reproductive success.
Students will determine the meaning of key terms as they are used in scientific texts.
Students will write an argument focused on the lesson's content by introducing a claim, providing evidence to support the claim, and using scientific reasoning to explain how the provided evidence supports the stated claim.

Procedures/Activities

Before Strategy/Engage: 25 minutes

1. Students should create a T-chart on their paper, with the left side labeled "Similarities" and the right side labeled "Differences".

2. The teacher should show the following video clip: "Time-Lapse: Watch Flowers Bloom Before Your Eyes" from National Geographic. As students view the video clip, they should create a list of the similarities and differences among the flowers shown on the video on their T-chart.

3. After students view the video clip, the teacher should create a T-chart on the interactive whiteboard. The teacher can ask students to share similarities and differences among the flowers they viewed on the video clip and create a class T-chart.

4. Next, the teacher should give each student a copy of "Flowering Plants Card Sort". Students will cut out the 12 cards and sort the cards into groups based on the students' current knowledge of flowering plants. After sorting their cards, students will read the article “Flowering Plants” from ck12.org. The students may read the text on an internet-capable technology device, or the teacher can make copies of the article prior to teaching the lesson. After students read the informational text, they should re-sort their cards into categories and give each category a title.

Note: Card sort was adapted from "The Beauty of a Flower-Structure and Function" from Better Lesson.

5. The teacher may allow students to share their categories and titles with the class and/or create a class list of categories using the interactive whiteboard.

During Strategy/Explore & Explain: 45 minutes

1. Students should be divided into collaborative groups of approximately four students each. The teacher should give each student a copy of the "Flower Dissection Lab Sheet" from "The Beauty of a Flower-Structure and Function" from Better Lesson. Each group of students will need the required materials to carry out the scientific investigation.

2. The students should perform the procedures on the lab sheet with their group members. This lab will require students to carefully dissect a flower and observe the various specialized structures. The students will collect specimens to view under the microscope. Students will create and label scientific sketches of the flower's specialized structures.

After Strategy/Explain & Elaborate: 45 minutes

Note: Students can continue to work in collaborative groups for this portion of the lesson, or the teacher may wish for students to complete this strategy independently.

1. The teacher should give each student a copy of the "Flower Seeking Pollinator Data Sheet" from California Academy of Sciences or allow students to view the data sheet using an internet-capable device. The students should observe the photographs and traits of the flowers shown on the data sheet. Students should examine the data table for patterns, such as:

Which traits attract the most pollinators?
What type of pollinators are attracted to each flower's specialized structures?

2. The teacher should give each student a copy of the "Pollinator Profile" from California Academy of Science or allow students to view the profiles using an internet-capable device. The students should examine the pollinator profiles and determine which specialized structures would attract that particular pollinator to a plant.

3. Using information from the "Flower Seeking Pollinator Data Sheet" and the "Pollinator Profile" from California Academy of Science, students will design a sketch of a unique flower (one not shown on the Data Sheet) that has specialized structures that will positively affect the plant's probability of reproductive success. The students will label the structures of the flower learned in the during strategy.

4. After designing a new flower, the teacher will give each student a copy of the "Claim Evidence Reasoning" Graphic Organizer. Before students begin their written response, the teacher should present the Claim-Evidence-Reasoning Grading Rubric to set expectations of the students' final assessment. The students should respond to the essential question listed at the top of the graphic organizer, "How will the specialized structures of your flower positively affect the plant's reproductive success?" The students will write a claim to respond to the question, provide evidence to support the claim, and use scientific reasoning to explain how the provided evidence supports the stated claim. Students should explain how the specialized structures of their created flower would positively affect the probability of successful reproduction of the plant using evidence from the informational text, lab activity, Data Sheet, and Pollinator Profile.

Assessment Strategies

Formative Assessment: The teacher should informally assess students in the before strategy as students create the T-chart. The teacher should review each student's card sort to ensure the student understood the main ideas and key vocabulary of the informational text. The teacher should informally assess students as they complete the lab activity in the during strategy of the lesson. The teacher should review each student's lab sheet to confirm the student was able to correctly identify and label the specialized plant structures.

Summative Assessment: The teacher should formally assess students at the conclusion of the lesson by reviewing each student's unique flower design sketch, which should include labels identifying the plant's specialized structures. The teacher should determine each student's achievement of the lesson's objectives by assessing the student's claim-evidence-reasoning writing using the rubric (Claim-Evidence-Reasoning Grading Rubric).

Acceleration

Students who require acceleration strategies can read an advanced version of the informational text in the before strategy: "Flowering Plants-Advanced" from ck12.org. After reading the advanced version of the informational text, students can respond to the corresponding discussion questions in a verbal or written format ("Flowering Plants Discussion Questions" from ck12.org). If student technology devices are available, students can respond to the questions in an online discussion or message board and use this technology to communicate their ideas with classmates.

Intervention

Students who require intervention strategies can visit the following website to perform a "virtual" flower dissection: "Life Cycle of a Plant" from Science Kids. This website also provides review opportunities on the specialized plant structures taught during the lesson.

Total Duration

91 to 120 Minutes

Background/Preparation

Student Background Information: As this lesson will serve as an introduction to the specialized plant structures that affect the probability of successful reproduction, students will not need background information on this concept. As written, this lesson requires students to use a microscope and create a dry mount slide with a thin cross-section of a plant's ovary, as well as a wet mount slide with the plant's pollen grains. If materials are not available for this portion of the lab activity, the teacher may wish to omit these steps. If students have not had experience with using a microscope or preparing slides, the following video clips provide detailed, illustrated steps to perform these tasks:

"Making Wet and Dry Mount Slides" from youtube.com-7:45

"How to Prepare a Wet Mount Slide" from youtube.com-2:30

"Using a Microscope" from youtube.com-6:59

At the conclusion of the lesson, students will design a unique flower with specialized structures that will positively impact the probability of successful reproduction of the plant and use a "claim-evidence-reasoning" format for their written explanation. If students do not have experience with this style of argumentative writing, the teacher can provide background knowledge and experience with this strategy using the following website:

"Helping Students Write About Claims and Evidence" from NSTA.org

Teacher Background Information: Flowering plants contain both male and female reproductive structures, which include the stamen, pistil, petals, and sepals. The stamen is the male reproductive structure of the flower and consists of a tall stalk that ends in an anther, which contains the pollen sacs. The pistil is the female reproductive structure of the flower and consists of a raised, sticky stigma to catch the male pollen, and a style to connect it to the ovary, which contains the egg. These specialized structures have evolved over time to ensure the flowering plant has a high probability of reproductive success. The stamen raises the pollen-holding anther up high, to ensure that animal pollinators or the wind will transport the pollen to the pistil. The stigma is sticky to help attract pollen for reproduction. The petals of a flower are brightly colored in order to attract animal pollinators. Sepals protect the flower before it blooms and are often green, which can camouflage the flower from consumers.

The teacher should preview the lesson in its entirety prior to teaching the lesson, as each individual teacher may have to make modifications to the lesson, depending on available materials. The teacher should make all required copies prior to teaching the lesson.

This lesson will make use of the "Flower Dissection Lab Sheet" from "The Beauty of a Flower-Structure and Function" from Better Lesson, which is available for download under section two. In order to download the lab sheet, the teacher will need to create a free account on the Better Lesson website.

This lesson was adapted from "The Beauty of a Flower-Structure and Function" from Better Lesson and "Flowers Seeking Pollinators" from California Academy of Sciences.

Materials and Resources

Student Materials (per student)

Notebook paper

Pencil or pen

Scissors

Colored pencils/crayons/markers/etc.

White paper

"Flowering Plants Card Sort" Note: Card sort was adapted from "The Beauty of a Flower-Structure and Function" from Better Lesson

"Flowering Plants" informational text from ck12.org (to be copied prior to lesson if internet-capable devices are unavailable to students)

"Flower Dissection Lab Sheet" from "The Beauty of a Flower-Structure and Function" from Better Lesson (available for download under Section 2)

"Flower Seeking Pollinator Data Sheet" from Calfornia Academy of Sciences (to be copied prior to lesson if internet-capable devices are unavailable to students)

"Pollinator Profile" from California Academy of Science (to be copied prior to lesson if internet-capable devices are unavailable to students)

"Claim Evidence Reasoning" Graphic Organizer

Student Materials (per group)

Flower for dissection (lilies are a good choice as they have large, visible structures)

Hand lens

Clear tape

Safety razor blade (for flower dissection)

Petri dish

Microscope slides and coverslips

Water (for wet mount slide)

Microscope

Website Links for Acceleration Strategy

Advanced informational text: "Flowering Plants-Advanced" from ck12.org.

"Flowering Plants Discussion Questions" from ck12.org

Website Link for Intervention Strategy: "Life Cycle of a Plant" from Science Kids

Teacher Materials

Teacher computer with internet access

Interactive whiteboard or projector with the ability to project sound

Video clip for before strategy: "Time-Lapse: Watch Flowers Bloom Before Your Eyes" from National Geographic YouTube-3:24

Claim-Evidence-Reasoning Grading Rubric from Boston Public Schools Science Department (copy per student)

Technology Resources Needed

Student Technology Resources

Internet-capable devices to view informational text (if available)

Teacher Technology Resources

Teacher computer with internet access

Interactive whiteboard or projector with ability to project sound

Approved Date

2016-12-28