Chapter 21, Problem 18A

Summary Introduction

To write:

The term for the given definition.

Introduction:

The diversity of plants and its classification depends on adaptation. The plants are classified into twelve divisions. These twelve divisions of plants are divided into two groups; the non-vascular plants and the vascular plants. The non-vascular plants have lack of specialized transport tissue while the vascular plants have specialized transport tissue.

Explanation of Solution

The sporophytic generation of seedless vascular plants like pterophyta they produce sporophytes without fertilization. They produce roots and thick underground stem called rhizome. This is a food-storage organ. The breakdown of this food storage organ releases the energy during the growth of the above ground structures.

Conclusion

The thick underground stem found in pterophyta is termed as rhizome. They are the food storage organ.