“视觉和听觉的形成”是初中生物教学中的难点,学生理解起来有困难。为此,笔者自制了“视觉的形成”模拟演示装置和“听觉的形成”模拟演示装置,并将上述两款演示装置应用于教学之中,取得了较好的效果。一、“视觉的形成”模拟演示装置1.材料与用具。凸透镜(如晶状体)、镜筒(如眼球的前后径)、有线摄像头(如视网膜、视神经)、“笔记本电脑”(如人的大脑,而屏幕相当于视觉中枢)、 “Visual and auditory formation ” is the difficulty of junior high school biology teaching, students understand it difficult. To this end, I made a “visual formation ” simulation demonstration device and “auditory formation ” simulation demonstration device, and the above two demonstration devices used in teaching, and achieved good results. First, “visual formation ” simulation demo device 1 materials and appliances. (Such as the lens), lens tubes (such as the anterior and posterior diameters of the eyeballs), wired cameras (such as the retina and optic nerve), “laptops” (such as the human brain and the screen equivalent to the visual center)