Science and Technology
Grade 7: Life Systems: Interactions Within Ecosystems
Overall Expectations
•demonstrate an understanding of the interactions of plants, animals, fungi, and micro- organisms in an ecosystem;
•investigate the interactions in an ecosystem, and identify factors that affect the balance among the components of an ecosystem (e.g., forest fires, parasites);
•demonstrate an understanding of the effects of human activities and technological innovations, as well as the effects of changes that take place naturally, on the sustainability of ecosystems.         
Specific Expectations
Understanding Basic Concepts        
•identify living (biotic) and non-living (abiotic) elements in an ecosystem;        
•identify populations of organisms within an ecosystem and the factors that contribute to their survival in that ecosystem;        
•identify and explain the roles of producers, consumers, and decomposers in food chains and their effects on the environment (e.g., plants as producers in ponds);        
•explain the importance of microorganisms in recycling organic matter (e.g., as decomposers);        
•identify micro-organisms as beneficial (e.g., yeast) and/or harmful (e.g., bacteria or viruses that cause disease);        
•interpret food webs that show the transfer of energy among several food chains, and evaluate the effects of the elimination or weakening of any part of the food web;        
•describe the process of cycling carbon and water in the biosphere;        
•investigate ways in which natural communities within ecosystems can change, and explain how such changes can affect animal and plant populations (e.g., changes affecting their life span, their gestation periods, or their ability to compete successfully);        
•identify signs of ecological succession in a local ecosystem (e.g., the presence of blueberries in an area recently devastated by fire; the presence of pioneer organisms that start the process of succession in sand dunes).         
Developing Skills of Inquiry, Design, and Communication        
•formulate questions about and identify the needs of various living things in an ecosystem, and explore possible answers to these questions and ways of meeting these needs (e.g., research the population levels of a species over time and predict its future levels on the basis of past trends and present conditions; determine how the structure of specific plants helps them withstand high winds, live on the surface of water, or compete for sunlight);        
•plan investigations for some of these answers and solutions, identifying variables that need to be held constant to ensure a fair test and identifying criteria for assessing solutions;        
•use appropriate vocabulary, including correct science and technology terminology, to communicate ideas, procedures, and results (e.g., use scientific terms such as biosphere, biome, ecosystem, species);        
•compile qualitative and quantitative data gathered through investigation in order to record and present results, using diagrams, flow charts, frequency tables, bar graphs, line graphs, and stem-and-leaf plots produced by hand or with a computer (e.g., use a chart to record the number of producers and consumers in a particular habitat);        
•communicate the procedures and results of investigations for specific purposes and to specific audiences, using media works, oral presentations, written notes and descriptions, charts, graphs, and drawings (e.g., design a multimedia presentation explaining the interrelationships of biotic and abiotic elements in a specific ecosystem).        
Relating Science and Technology to the World Outside the School        
•investigate the impact of the use of technology on the environment (e.g., the “greenhouse effect”; redirection of water flow for human needs; use of pesticides);        
•investigate the bio-economical costs and benefits of the recycling and waste- disposal industries;        
•explain the importance of plants as sources of energy (e.g., food, fossil fuels), as producers of carbohydrates and oxygen (e.g., phytoplankton), and as habitats for wildlife;        
•describe the conditions in an ecosystem that are essential to the growth and reproduction of plants and micro-organisms, and show the connection between these conditions and various aspects of the food supply for humans;        
•identify the importance of plants in the Canadian economy (e.g., in farming, forestry, drug manufacturing, the nursery industry) and describe the impact of the industrial use of plants on the environment;        
•explain the long-term effects of the loss of natural habitats and the extinction of species (e.g., loss of diversity of genetic material, both plant and animal);        
•identify and explain economic, environmental and social factors that should be considered in the management and preservation of habitats (e.g., the need for recycling; the need for people to have employment).         
Student Name:        
 Expectations: Copyright The Queen's Printer for Ontario, 1998.  Format: Copyright B.Phillips, 1998.