Question

Write two or more paragraphs comparing and contrasting angiosperm reproduction from gymnosperm reproduction. Don’t just list the characteristics! You may use slide or live specimens, but make sure to focus on characteristics that will help you in distinguishing angiosperm versus gymnosperm. What would be some evolutionary advantages that angiosperms have compared to gymnosperms? Why would these be advantages?

Answer 1

Angiosperm reproduction and gymnosperm reproduction

The angiosperm reproduction are called flowering plants where the seeds are enclosed within the ovary and the gymnosperms are those which do not have fruits or flowers and the seeds are present in naked form. The reproductive structure of gymnosperm is cones which are uni-sexual and the ovules are not located within the ovary. They are generally seasonal which die during autumn and the tissues produced are triploid. They have a unisexual or bisexual reproduction system and the cotyledons are either monocots or dicot. The pollen grain germinates directly on ovule micropyle and the process of fertilization is simple. In gymnosperms the xylem contains only tracheids and the phloem has no companion cells. The gymnosperms have alternate generations where the male gametophyte is pollen and the female gametophyte is present in archegonium. As the male gamete falls on the tube cell, it forms the pollen tube which allows the generative cell migrate towards female gametophyte through micropyle. The male gametophyte that contains the generative cell splits to two sperm nuclei where one fuses with sperm and other degenerates. Once the fertilization is done, the diploid zygote is formed and it starts dividing by mitosis forming embryo.

In case of angiosperm reproduction, they have seeds which are found in the flower and the eggs are fertilized and develop into seeds within the ovary. The angiosperms undergo reproduction through the process of pollination and the male sex organ is stamen where anther is present in one end and pollen is made. The female part is the pistil and the stigma carry the pollen down to ovary through style where the fertilization takes place.

There are couple of evolutionary advantage that the angiosperm have over the gymnosperm and one of the most important one is ability to undergo pollination. The flowers in the angiosperm give evolutionary advantage and due to their color and nectar they attract organism which help in pollination and distribute and disperse seed. They also have seed packaged. The angiosperms also do not require for reproduction.