初中生理卫生课和高中新版生物选修课,都有用显微镜观察血涂片的实验。制作血涂片需在耳垂或指尖处取血样。凭常识或生活经验,每个人都知道被采血者会感到不同程度的疼痛。为了消除畏惧心理和激发学生突趣,教师可在自己指尖作无痛取血示范。在皮肤的结构和功能一节中告诉我们:“真皮里有能感受冷、热、触、痛等刺激的感 In junior high school physics and health classes and new high school fresh elective courses, there are experiments to observe blood smears with a microscope. Blood smears should be taken at the earlobe or fingertips. Based on common sense or life experience, everyone knows that the person who is taking blood will feel different degrees of pain. In order to eliminate fear and stimulate student interest, teachers can perform painless blood sampling at their fingertips. In the structure and function section of the skin, tell us: "There is a sense of sensation of cold, heat, touch, and pain in the dermis.