outer pericycle

例句：

1. 1. The outer pericycle is responsible for the plant's defense against herbivores.
   外周细胞负责植物对食草动物的防御。
2. 2.In the process of photosynthesis, the outer pericycle plays a crucial role in converting light energy into chemical energy.
   在光合作用过程中，外周细胞起着至关重要的作用，将光能转化为化学能。
3. 3. The outer pericycle also contains cells that produce enzymes and hormones, which are essential for plant growth and development.
   外周细胞还包含产生酶和激素的细胞，这些物质对于植物的生长和发展至关重要。