Question

A trend in the evolution of plants has been an increase in the size of plants and a decreasing dependence on water for reproduction. Explain the above trend through a comparison of the bryophytes and the angiosperms​

Answer 1

Answer: The term EVOLUTION in the study of plants is referred to as the adaptive changes that have taken place which may lead to the development of new species that exists and survive in different ways from the species which they evolved.

Explanation:

In the evolution pattern of plants, it has been an increase in the size of plants and a decreasing dependence on water for reproduction These changes can be identified in the life history of bryophytes and the angiosperms both of which belongs to the plant kingdom.

BRYOPHYTES do not have any System for conducting food and water from one part of the plant to another. This restricts their size. Examples of bryophytes include: liverworts and mosses. Also, bryophytes show a distinct alterations of generation, which means there are presence of sexual( gametophyte) and asexual stage( sporophyte) that are often morphologically, and sometimes chromosomally, distinct. The sporophyte is always attached and dependent on the gametophyte which produces motile male gametes known as spermatozoa and non-motile female gametes known as ova. Water is essential for fertilization.

ANGIOSPERMS are the flowering plants. They form the largest group in the plant kingdom. There are thousands of species which differ greatly in size and form. They have adapted to almost every kind of habitat. They are seed producing vascular plants. They have well developed roots, stems and leaves. The efficient seed dispersal of seed plants account for their continued existence and widespread occurrence. Fertilization is brought about by pollination, therefore they do not depend on water for reproduction.

From the above description of bryophytes and angiosperms, the ANGIOSPERMS are more EVOLVED than the BRYOPHYTES because they possess water conducting vessels with unrestricted sizes and do not depend on water for reproduction while bryophytes are restricted in size and depends on water for reproduction.