Life Cycles. 5.10C Describe the differences between complete and incomplete metamorphosis of insects. Supporting Standard

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1 Life Cycles Grade 5 Science Unit: 10 Lesson: 01 Suggested Duration: 5 days Lesson Synopsis: In this lesson students, will observe several insects during their life cycle. Students will learn to differentiate between complete and incomplete metamorphosis. TEKS: 5.10 Organisms and environments. The student knows that organisms undergo similar life processes and have structures that help them survive within their environments. The student is expected to: 5.10C Describe the differences between complete and incomplete metamorphosis of insects. Supporting Standard Scientific Process TEKS: 5.2 Scientific investigation and reasoning. The student uses scientific methods during laboratory and outdoor investigations. The student is expected to: 5.2D Analyze and interpret information to construct reasonable explanations from direct (observable) and indirect (inferred) evidence. 5.2F Communicate valid conclusions in both written and verbal forms. 5.3 Scientific investigation and reasoning. The student uses critical thinking and scientific problem solving to make informed decisions. The student is expected to: 5.3B Evaluate the accuracy of the information related to promotional materials for products and services such as nutritional labels. 5.4 The student knows how to use a variety of tools and methods to conduct science inquiry. The student is expected to: 5.4A Collect, record, and analyze information using tools, including calculators, microscopes, cameras, computers, hand lenses, metric rulers, Celsius thermometers, prisms, mirrors, pan balances, triple beam balances, spring scales, graduated cylinders, beakers, hot plates, meter sticks, magnets, collecting nets, and notebooks; timing devices, including clocks and stopwatches; and materials to support observations of habitats or organisms such as terrariums and aquariums. GETTING READY FOR INSTRUCTION Performance Indicator(s): Write a description of the differences in insect metamorphosis. Analyze the advertisements for various pesticide products. Justify which products would work best for various insects that undergo complete and incomplete metamorphosis. (5.3B; 5.10C) 4J; 5B Key Understandings and Guiding Questions: Some insects go through complete metamorphosis while other insects go through incomplete metamorphosis during their life cycle. How does incomplete metamorphosis differ from complete metamorphosis? What are the stages of complete metamorphosis? What are the stages of incomplete metamorphosis? Vocabulary of Instruction: metamorphosis complete metamorphosis incomplete metamorphosis nymph egg larva adult chrysalis pupa runoff pesticide insecticide 2012, TESCCC 05/21/13 page 1 of 6

2 Refer to section for materials. Teacher Resource: Complete Handout: Incomplete of an Insect Teacher Resource: PowerPoint: Teacher Resource: PowerPoint: A Lesson in Ecosystems: The Impact of Insects Handout: Comparing (see Advance Preparation, 1 per 2 students) Teacher Resource: Comparing KEY Handout: Insecticides PI (1 per student) Teacher Resource: Insecticides KEY Teacher Resource: Performance Indicator Instructions KEY (1 for projection) Advance Preparation: 1. Locate and preview an approved time lapse video clip of an insect undergoing metamorphosis for the Engage portion of the lesson. You may find it helpful to include the terms neok12 and metamorphosis in your search. 2. Obtain mealworms. 3. Order corn earworms from the USDA ( they are free of charge for educators. Please be aware that there is a time frame in which to order these: SPRING: 2013: Feb 1 March 31st (inclusive). 4. Set up habitats (terrariums) in the room from which students will observe each insect life cycle. 5. Prepare containers of organisms for each group (mealworm and corn earworm). Each container should have a larva, a pupa, and an adult. 6. Prior to the EXPLORE/EXPLAIN and ELABORATE lessons, preview the Teacher Resource: PowerPoint: and print the notes. 7. Make one copy of Handout: Comparing for each pair of students and cut into halves. 8. Prepare attachment(s) as necessary. Background Information: During this lesson, students will look at how organisms change through larva/pupa stages or nymphs into adults. Some organisms go through metamorphosis throughout the year. However, many more are going through the process in the spring months. The content standard addressed in this unit is a Supporting Standard for Grade 5. GETTING READY FOR INSTRUCTION SUPPLEMENTAL PLANNING DOCUMENT Instructors are encouraged to supplement and substitute resources, materials, and activities to differentiate instruction to address the needs of learners. The Exemplar Lessons are one approach to teaching and reaching the Performance Indicators and Specificity in the Instructional Focus Document for this unit. Instructors are encouraged to create original lessons using the Content Creator in the Tools Tab located at the top of the page. All originally authored lessons can be saved in the My CSCOPE Tab within the My Content area. INSTRUCTIONAL PROCEDURES Instructional Procedures ENGAGE Introducing 1. Introduce the lesson on metamorphosis by showing a teacher selected time lapse video clip of an insect undergoing metamorphosis (see Advance Preparation). 2. At the end of the video clip, Ask: What was happening in the video? Allow students the opportunity to respond to this question. Although students have been discussing life cycles since kindergarten, this may be the first time they have used the word metamorphosis. 3. Ask/Say: What do you think metamorphosis means? Students may have noticed that the insect has gone through different stages of NOTE: 1 Day = 50 minutes Suggested Day 1 Instructional videos can be located from a variety of sources (see Advance Preparation). Misconception: Students may think the larval stage includes a different organism than in the adult stage. 2008, TESCCC Revised 09/29/08 page 2 of 6

3 development. The insect changes as it develops. This change of form (or morph) is called metamorphosis. 4. Instruct students to record the definition of metamorphosis in their science notebook. Science Notebooks: Throughout the lesson it is imperative for students to record all new vocabulary and definitions in their notebooks. Students should have this opportunity in order to use the information as reference/resource later in the lesson. Students will use their science notebooks to record observations throughout the five day lesson. EXPLORE Describing Complete 1. Prior to this lesson, set up two observation areas in the classroom (see Advance Preparation). One observation area should include mealworm larvae (or darkling beetle larva). The second area should include the moth larva (corn earworm). 2. Instruct students to set up a chart or table in their science notebooks on which they will record observations of the insects over the next five days. 3. Divide the class into groups of 3 4 students. Distribute paper, hand lenses, a container with mealworms, and one container with corn earworms to each group. Make sure each container gets a larva, a pupa, and an adult. The presence of eggs is assumed. 4. Instruct students to carefully observe and draw each stage of the insects life cycle on the plain paper. The drawings should be detailed and large enough for students to label the different body structures. A microscope could be set up so students could look for evidence of eggs. 5. Guide the students in a group discussion about their observations. Ask/Say: How many stages in the life cycles of the insects did you observe? Answers will vary There are four distinct stages of development in the life cycle of these insects: egg, larva, pupa, and adult. The changes that these insects undergo in their life cycle are called complete metamorphosis. In what ways were the different stages of development similar? Answers will vary, but should include, a segmented body, eyes, and a mouth. 6. Display the Teacher Resource: Complete. 7. Instruct students to cut out and place the pictures that they drew when observing the insects in the correct developmental order. Monitor students to ensure that they do not mix the life cycle pictures of the two insects, so that they can affix them on two separate pages of the science notebook. Use the Teacher Resource: Complete as a guide to label and order the stages of development correctly. Suggested Day 1 (continued) mealworms (20 30 per class) potato (1 per habitat) apple (1 per habitat) bran cereal (1 cup per habitat) corn earworms (@20 per class) suitable habitat for each specimen group (1 terrarium per habitat) microscopes (1 2 per class) hand lens (1 per student) paper (plain, 1 piece per student) scissors (1 pair per student) glue (stick or liquid, 1 container per group) Teacher Resource: Complete Mealworms are easy to transport. The adult form, the darkling beetle, does not fly. Mealworms can be kept in a small box. Give your mealworms potatoes and apples along with bran cereal. Corn earworms (moths) are available through the USDA ( RequestCornEarWorms.htm); they are free of charge for educators. They supply the larva and food for each pair of students to have a larva to observe. 8. Instruct student groups to return the organisms to the class habitats. 2008, TESCCC Revised 09/29/08 page 3 of 6

4 Ensure that the organisms are put in the correct habitat. Ask/Say: What are the components of the ecosystem in which the insects we are observing live? The insect ecosystem includes both biotic and abiotic factors. Describe the living interactions that occur within the insect s ecosystem. The insects interact with each other as they look for food and reproduce. With what nonliving elements do the insects interact? The insects need air, water, and space to grow. 9. Instruct students to record the definition of complete metamorphosis in their science notebooks. Misconception: Students may think the larval stage includes a different organism than in the adult stage. STAAR Note: This is a good opportunity to review the Readiness Standard 5.9A in which the student is expected to observe the way organisms live and survive in their ecosystem by interacting with the living and nonliving elements. EXPLORE/EXPLAIN Describing Incomplete Suggested Day 2 1. Lead the students in a brief discussion reflecting on their understanding of complete metamorphosis. If students continue to have misconceptions about complete metamorphosis, use the discussion as a formative assessment to guide instruction. 2. Distribute the Handout: Incomplete of an Insect to each student. Guide students in making careful observations on the life cycles shown by asking the following questions: Ask/Say: What do you notice about the life cycles of the grasshopper and praying mantis? (Students should notice that both life cycles have three stages.) There are three distinct stages of development in the life cycle of these insects: egg, nymph, and adult. Why do you think these life cycles are still called metamorphosis even though there are only three stages of development? (Students should notice that there is a visible change between each of the life cycle stages.) The changes that these insects undergo in their life cycle are called incomplete metamorphosis. In what ways do the different stages of development compare? scissors (1 pair per student) glue (stick or liquid, 1 container per group) Handout: Incomplete of an Insect Teacher Resource: PowerPoint: Check for Understanding: Use the PowerPoint presentation as an opportunity for students to reflect on the Handout: Comparing. Additionally, use the writing prompt as a formative assessment. 3. Project the PowerPoint:. View each slide (1 7) and thoroughly discuss the information on each slide. Slide 8 is used later in the lesson. Science Notebooks: Additionally, students may attach their handouts to their notebooks. EXPLORE/EXPLAIN A Lesson in Ecosystems: The Impact of Insects Suggested Day 3 1. Instruct students to make observations of the insects in the habitats. Record any changes they notice on the chart in their science notebooks. 2. Project the Teacher Resource: PowerPoint: A Lesson in Ecosystems: The Impact of Insects. 3. After showing the PowerPoint, allow time for students to discuss the impact humans have on the environment. hand lens (for observing insects in habitats, 1 per student) Optional paper (chart, 1 sheet per teacher, optional) marker (1 per teacher) 4. Guide students in the creation of a food web or food chain using organisms 2008, TESCCC Revised 09/29/08 page 4 of 6

5 that are local to their area. Students should draw this in their science notebooks. 5. Instruct students to reflect on the consequences of the removal of one organism in the food web or food chain. In their science notebooks, students should write 2 3 sentences discussing the impact of humans on the environment through the use of pesticides/insecticides. 6. Conclude the lesson by asking how understanding life cycles of insects is important. Accept appropriate answers. Teacher Resource: PowerPoint: A Lesson in Ecosystems: The Impact of Insects In order to make the connection between the beneficial insects and students, choose organisms that are present in your local area when creating the food chain and food webs. STAAR Note: The Teacher Resource: PowerPoint: A Lesson in Ecosystems: The Impact of Insects allows for reviewing TEKS 5.9B and 5.9C. 5.9C uses the term such as overgrazing or building highways. Such as is used when the information is intended as representative samples only. Teachers may choose from those listed or select others, as others may be assessed. This PowerPoint includes the runoff of pesticides as an example. ELABORATE Comparing Suggested Day 4 1. Distribute one half of the Handout: Comparing to each student. Instruct students to create a three column chart in their science notebooks. Students should label the three columns: Complete, Both, and Incomplete. 2. Instruct students to cut out each of the small cards and place each card in the column where they predict it should go. Complete Both Incomplete scissors (1 pair per student) glue (stick or liquid, 1 container per group) Handout: Comparing (see Advance Preparation, 1 per 2 students) Teacher Resource: Comparing KEY Teacher Resource: PowerPoint: (from previous activity) 3. Project the Teacher Resource: PowerPoint: (slides 3 7) as a review. Allow students the opportunity to revise their predictions. 4. After students have made revisions, project slide 8. Provide students one more opportunity to reflect on their understanding and revise the column cards before affixing them onto the chart in their science notebooks. This graphic organizer is actually a modified Venn diagram. It may be easier for students to begin with a Venn diagram and convert the data into the table form. 5. Facilitate a discussion focused on the differences between complete metamorphosis and incomplete metamorphosis. Ask: How does incomplete metamorphosis differ from complete metamorphosis? Check for Understanding: The chart students create provide the teacher with a formative assessment 2008, TESCCC Revised 09/29/08 page 5 of 6

6 What are the stages of complete metamorphosis? What are some examples of insects that undergo complete metamorphosis? What are the stages of incomplete metamorphosis? What are some examples of insects that undergo incomplete metamorphosis? opportunity on the student understanding of complete and incomplete metamorphosis. EVALUATE Performance Indicator Suggested Day 5 Performance Indicator Write a description of the differences in insect metamorphosis. Analyze the advertisements for various pesticide products. Justify which products would work best for various insects that undergo complete and incomplete metamorphosis. (5.3B; 5.10C) 4J; 5B 1. Refer to the Teacher Resource: Performance Indicator Instructions KEY for information on administering the assessment. Handout: Insecticides PI (1 per student) Teacher Resource: Insecticides KEY Teacher Resource: Performance Indicator Instructions KEY (1 for projection) 2008, TESCCC Revised 09/29/08 page 6 of 6