Chapter 21.3, Problem 5MI

Summary Introduction

To describe:

The structures and common locations of ferns and horsetails.

Introduction:

Ferns and horsetails are the first of the seedless, vascular land plants. They reproduce with spores and are found in moist environments as they require water at the time of fertilization.

Answer to Problem 5MI

The structures and common locations of ferns and horsetails are given in the table:

	Ferns	Horsetails
Structure	In ferns roots produced from sporophyte. Rhizome is stem that stores food. Ferns have photosynthetic fronds. Spores are formed in sporangium.	Stems are ribbed, hollow with strobili at tips. Leaves and roots are scale-like.
Location	Found in moist or dry environments.	Found in damp environments and marshes.

Explanation of Solution

In ferns, stem may be underground as a rhizome with adventitious roots which absorb water and nutrients from the soil. They have compound leaves called fronds. Fronds are photosynthetic organs that also carry reproductive structure. Ferns grow in various environments, they can grow in damp, shady, and moist areas, but can develop and survive also in dry conditions.

In horsetails, the stems are long, ribbed, narrow, and hollow stems with strobilus at tips. The stem is characterized by the presence of joints or nodes. Leaves and branches come out as whorls from the evenly-spaced joints. The needle-shaped leaves do not contribute greatly to photosynthesis, the majority of which takes place in the green stem. Horsetails grow in wet environments and marshes.