Chapter 22, Problem 25A

Summary Introduction

To write:The reasons why eudicot stems can have a greater increase in diameter than most monocot stems.

Introduction:Because of the presence of chloroplasts, some stems, such as asparagus, are soft, flexible and green, and thus can perform photosynthesis. These stems are termed herbaceous and this type of stem is found in most annual plants. Palms and bamboo have stiff, fibrous stem.

Explanation of Solution

The principal function of stems is to support the leaves and reproductive structures of a plant. Cells formed by apical meristem result in the length of the stem growing. A rise in stem diameter provides additional support as the plant grows taller. A rise in stem diameter in eudicots is mostly due to an increase in cell size.The increase of cell diameter in eudicot stems is due to the vascular cambium producing cells. The year-round production of xylem and phloem can yield annual growth rings.

Conclusion

Thus, the stems of the eudicot may have a greater diameter increase than most stems of the monocot. You can estimate a tree's age by counting the annual growth rings at the base of its trunk.