Chapter 23, Problem 1NS.1QC

Summary Introduction

To determine:

The determination of the age of bryophytes present in the retreating glaciers is useful information.

Introduction:

Bryophytes are non-vascular, seedless plants. They are the most primitive land plants. They lack true stem, leaves and roots. Bryophytes require moist atmosphere for growth. They are photosynthetic plants. They include liverworts, hornworts and mosses.

Explanation of Solution

Glaciologists are those who study glaciers to know about the pre-historic world. With the help of glaciers they can determine the previous atmosphere, types of plants and animals that have evolved and lived thousand years ago on earth. The melting and retreating of glaciers due to environmental change helps to discover the remains of pre-existing organisms buried in glaciers.

Bryophytes were the first land plants that were evolved and they lack true stem, roots and leaves. They were able to tolerate the extreme conditions. The tissue samples are collected from gametophytes such as rhizoids, leaf and stem structures help to retrieve information about the growth and the differentiation of these plants. It also provides clue for tolerant capacity of bryophyte in extreme conditions. Their age is also determined by the study of glaciers and it is estimated that their age is not more than $400$ years.

Conclusion

The study of glaciers provides the information related to the age of the bryophyte, the factors responsible for their tolerance against extreme conditions, and their evolution evidences.