GRADE 7 Unit 8: Structure and Function of Cells

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1 GRADE 7 Unit 8: Structure and Function of Cells 2010 TEKS 1998 TEKS Curriculum and Instruction Considerations 7.11 The student knows that populations and species demonstrate variation and inherit many of their unique traits through gradual processes over many generations The student knows the relationship between structure and function in living systems. Unit 8: Structure and Function of Cells (23 days) 7.12C Recognize levels of organization in plants and animals including cells, tissues, organs, organ systems, and organisms. Recognize LEVELS OF ORGANIZATION IN PLANTS AND ANIMALS cells tissues organs organisms systems and different from the Describe the similarities, differences and relationships between systems within systems. Note: Differentiating between structure and function in living systems has been removed from 6 th grade. It is important that 6.10C Identify how structure complements function at different levels of organization including organs, organ systems, organisms, and populations. Identify HOW STRUCTURE COMPLEMENTS FUNCTION AT DIFFERENT LEVELS OF ORGANIZATION cells tissues organs organisms populations These TEKS moved from 6 th grade to 7 th grade. Although 6 th grade Unit 5 covers most of the TEKS it would be unfair to the students to reuse those lessons. Lesson 1-17 days Key Understandings: All organisms are composed of cells. Each cell has a specific function within an organism. Plant cells differ from animal cells in structure and function. The shape of a cell is directly related to the function of that cell. Performance Indicators: Create a cell analogy (cell to a school, factory, etc.). Indicate the structure and function of the cell organelles to the structures in the analogy. (7.12,D) 1. Show students a box marked unknown specimen 2. Tell students that this specimen was found near the school by a parent. The parent did not know what it was so they brought it by for advice. 3. Tell the students that the specimen inside is 2010, TESCCC 10/20/10 page 1 of 5

2 students have an introductory understanding of the differences between structure and function and how they are related to each other. 7.12D Differentiate between structure and function in plant and animal cell organelles including cell membrane, cell wall, nucleus, cytoplasm, mitochondrion, chloroplast, and vacuole. Differentiate BETWEEN STRUCTURE AND FUNCTION IN PLANT AND ANIMAL CELL ORGANELLES cell structure and function of organelles cell membrane cell wall nucleus cytoplasm mitochondrion chloroplast vacuole plant cells differ from animal cells in structure and function cell walls large vacuoles the shape of a cell is directly related to the function of that cell nerve muscle red blood 6.10B Determine that all organisms are composed of cells that carry on functions to sustain life. Determine CELLS OF DIFFERENT FUNCTION cell structure and function of organelles cell membrane cell wall nuclear membrane and nucleus cytoplasm organelles mitochondria vacuole endoplasmic reticulum ribosomes Golgi apparatus plant cells differ from animal cells in structure and function cell walls large vacuoles the shape of a cell is directly related to the function of that cell nerve muscle red blood very unique. Build up an air of suspense about what is inside the box. Tell the students that you are thinking about calling in an expert from the local university because you too have never seen anything like it before. It might even be a new form of life! But before you call the experts, you want to be sure it would be embarrassing to call someone in if it is not even a living thing. 4. Have students work in small groups to develop a list of characteristics the specimen should have if indeed it is a living thing. 5. Have each group create a graphic organizer with the characteristics to present to the class. 6. After each group has shared their lists, develop a master list of the characteristics of life to display throughout the semester. 7. Do not open the box yet or give students any hints as to what is inside. Virtual Dissections- Find an on line source that allows students to virtually dissect an animal AND a plant. Remind students that they need to look for the levels of organization. This should take at least two instructional days (one for plants and one for animals) Lead a discussion over the levels of organization. Make the point that all living things are made of cells. Talk about Schleiden and Schwann. Observe cells under the microscope. Notice the structure of cells. 2010, TESCCC 10/20/10 page 2 of 5

3 guard cell VI. Biology A3 Describe the structure and function of major sub cellular organelles. VI. Biology A6 Know the structure of membranes and how this relates to permeability. 7.12E Compare the functions of a cell to the functions of organisms such as waste removal. Compare FUNCTIONS OF A CELL TO FUNCTIONS OF ORGANISMS waste removal extracting energy from food VI. Biology F2 Describe, compare, and contrast structures and processes 6.5 The student knows that systems may combine with other systems to form a larger system. 6.5B Describe how the properties of a Describe SYSTEM PROPERTIES VS. PROPERTY OF PARTS living systems Looking at Cells Alive website to look at the variation in the size and shapes of cells. Ask students if the structure of the cell relates to its function. Use the microscope to observe a wide variety of cells: nerve cells, muscle cells, red blood cells, guard cells. Have students draw detailed drawings labeling the parts of the cell. Discuss the difference between structure and function. Talk about the specific function of each cell and relate it to the structure. Explore/ Cells form tissues organs---> organ systems- > organisms Allow students to observe paramecium, Euglena, and other protists using the microscope. At the end of this class, ask students if these organisms are single celled, what characteristics and functions do they have? (Refer to the list generated at the beginning of this lesson) Ask students if cells must do those things, how do they do them? Ask students which organelles they remember from last year. Assign each group an organelle (refer to the specificity). Students are to research the structure and function of the organelle and create a 3D model of the cell part. 2010, TESCCC 10/20/10 page 3 of 5

4 that allow gas exchange, nutrient uptake and processing, waste excretion, nervous and hormonal regulation, and reproduction in plants, animals, and fungi; give examples of each. Use student models of organelles to model a cell within the room. The air would represent the cytoplasm. Model both a plant and animal cell. Have students record in their journals the differences between plant and animal cells. 7.12F Recognize that according to cell theory all organisms are composed of cells and cells carry on similar functions such as extracting energy from food to sustain life. Recognize ACCORDING TO CELL THEORY ALL CELLS AND CELLS CARRY ON SIMILAR FUNCTIONS cell theory all organisms are composed of cells skin cells come from skin cells 6.10B Determine that all organisms are composed of cells that carry on functions to sustain life. Determine CELLS OF DIFFERENT FUNCTION cell theory all organisms are composed of cells the cell is the basic unit of structure and function in living organisms cells come from other cells by cell reproduction (except the original As students go over the functions of the cell parts, relate them back to the list of things living things must do. Based on what you know design a cell that has a specific function in an organism and label the organelles with their function. Evaluate: Performance indicator- Analogy Performance Indicators: Write a newspaper article declaring that spontaneous generation has been rejected. Include "interviews" with scientists contributing to the cell theory. Use examples showing how functions of cells compare to the functions of organisms to support the theory. (7.12C, E, F) Lesson 2-8 days Show some of the student drawings from the elaborate in lesson 1. Ask students if the cell were actually alive and not a model, where would it have come from? Introduce the next part of the cell theory- cells 2010, TESCCC 10/20/10 page 4 of 5

5 the cell is the basic unit of structure and function in living organisms each cell has a specific function within an organism extracting energy from food to sustain life cells come from other cells by cell reproduction (except the original cell) mitosis overview Note: Relate cell theory to structure and function. VI. Biology F2 Describe, compare, and contrast structures and processes that allow gas exchange, nutrient uptake and processing, waste excretion, nervous and hormonal regulation, and reproduction in plants, animals, and fungi; give examples of each. cell) come from other cells by cell reproduction. (refer to characteristics of living things.. All living things reproduce). Allow students to look at prepared slides of onion root tips. Have them draw cells. Challenge them to find at least ten different looking cells to draw from the slide. Basic overview of mitosis. Use the phases, but understand the purpose of this is to understand that cells reproduce, not memorize the details of each step. Have student create a mitosis flip book. A sample of one can be found at look under the biology tab. Have students research topics such as spontaneous generation, early ideas on where living things originated and scientists including Schleiden, Schwann, Virchow, Spalanzini. Have students present the information to the class. Evaluate: Performance Indicator Newspaper article. 2010, TESCCC 10/20/10 page 5 of 5