Living Things and the Environment

Unit Overview

This Unit aims to develop in students the basic understanding of the interrelationship between living things and the environment. Students will conduct different practical activities, such as by investigating the necessary conditions for photosynthesis to occur. Students will learn how plants use light energy, carbon dioxide and water to make food and release oxygen as a by- product. In the activities, students will perform data processing to analyse the changing trends of oxygen consumption or oxygen production, thereby cultivating scientific thinking to propose explanations based on observed phenomena. This Unit also explains the importance of respiration in releasing energy within cells, and explains the complementary roles that photosynthesis and respiration play in carbon and oxygen balance in Nature. Learning the concepts of “ecosystem” and “biodiversity”, such as distinguishing between producers, consumers and decomposers, and analysing food webs to understand relationships such as predation, competition, and symbiosis, help students understand how life could sustain on the earth. Teachers may arrange activities to design micro-ecosystems, facilitating students to observe how the entire system is affected when the number of certain organisms changes, thereby understanding the importance of biodiversity. Students will also understand the impact of human activities on habitats and species survival, thereby cultivating a sense of responsibility and proper values in protecting the ecosystem. “Climate change” is an important issue encompassing science, technology, the environment, and society. To facilitate students to gain a deeper understanding of the interconnections among its various factors, teachers should actively consider collaborating with other subjects (e.g. junior secondary geography) when planning the learning and teaching on this topic. Interdisciplinary project learning could facilitate students to objectively evaluate the impact of the greenhouse effect on the natural environment, explore the interrelationships among photosynthesis, respiration, ecosystems, and climate change, thereby assisting them appreciate the concept of “change and constancy”. Teacher can also design other appropriate learning and teaching activities to enable students to develop and master the following skills: a) using a set of general observations, trend or models to deduce a specific result b) making inferences to the best possible explanation to the observed phenomenon c) identifying independent variables, dependent variables and control variables d) setting up a controlled experiment to minimise confounding factors to identify causation e) choosing from alternative experimental methods or improving the method for a scientific investigation f) commenting the reliability of a scientific measurement or a scientific investigation g) using tables and graphs for data analysis h) organising the claim, evidence and reasoning clearly in scientific discussions