Chapter 5 Population Regulation I.Teaching Objective: 1.Know why a population change in size and what factors can determine the population size. 2.Help the students to master types of Population Growth and Density Dependent Forces and Density Independent Forces. 3.Help the students to solve the linguistic difficulties and master the focal points occurring in the Chapter. L,Focal Points and Difficulties in the Chapter(教学重点和难点) 1.Focus Mechanisms of population regulation:Why are some species rare?What factors regulate population size? 2.Difficulties II.Methodology Powerpoint presentation will be the main method.Blackboard will be an assistance.Some beautiful diagrams have been prepared for visualization. V Presentation(课堂讲解，学时分配为2学时左右) Step 1.Warm-up Activity List the main vocabulary in the chapter and explain Let the students have a understanding about the main problems discussed in the chapter