1. The structural hierarchy of Chinese cabbage seedlings is cells → tissues → roots, stems, leaves, flowers, fruits, seeds → Chinese cabbage seedlings.

2, biological structure level:

Animals: cells → tissues → organs → systems → animal bodies.

Plants: Cells → Tissues → Organs → Plants

3. Concepts at all levels:

① Fine cells: Cells are the basic structural and functional units of organisms.

② Tissue: It consists of a group of cells and interstitial cells with similar morphology, structure and function.

(3) Officials: Different organizations are grouped together in a certain order.

④ System: It can be combined with multiple organs that perform one or several physiological functions in a certain order.

⑤ Individual: An organism whose complex life activities are coordinated by different organs or systems.