Morphological structure of Chinese cabbage flowers and fruits: Students experiment in groups, observe and dissect the flowers and fruits, fill in the observation record form, and teachers patrol and guide the students in the experiment. (1) Observe the color of Chinese cabbage flowers. The shapes of calyx and corolla, sepals and petals are dragged layer by layer from the outside to the inside like dissecting cabbage flowers, arranged in corresponding positions, and carefully observed. The lesson "The Structure of Flowers" mentioned that the observation of flowers should require students to be clear: 1. Observe what-Chinese cabbage flowers. 2. How to observe-Use tweezers to tear off all parts of the cabbage flower layer by layer from the outside to the inside, arrange them on white paper, and then count how many sepals and petals it has. 3. What was observed-sepals (four), petals (four), stamens (six: four long and two short) and pistil (one). Only through such requirements can students achieve good observation results in observation.