Reproduction is one of the essential properties of any living organism. Reproduction consists in increasing the number of individuals.
In plants, asexual and sexual reproduction is distinguished.
In the process of asexual reproduction, one parent organism is involved, which produces two or more offspring. Descendants are identical to each other and to the parent organism. Asexual reproduction is subdivided into asexual (sporulation) and vegetative reproduction.
1. Actually asexual reproduction (sporulation).
Spores reproduce unicellular and multicellular algae, mosses, ferns, horsetails, and moss.
The spore is a specialized cell. It separates from the mother plant and, once in favorable conditions, germinates, forming a new plant. One plant can form thousands and millions of spores, of which only a few will germinate and give new generations of plants.
On the underside of the fern leaves, sporangia with spores can be seen.
2. Vegetative reproduction – reproduction using the vegetative parts of the plant: stems, roots, leaves, bulbs, tubers, etc. The new individual inherits all the characteristics and properties of the mother’s organism.
In the process of sexual reproduction, a new organism is formed as a result of the fusion of sex cells (gametes).
Distinguish between male gametes (spermatozoa – motile and sperm – motionless) and female gametes (eggs).
The process of fusion of male and female gametes is called fertilization.
After the fusion of gametes, a zygote is formed (from the Greek word “zygotos” – joined together).
The embryo of the future plant develops from the zygote, which bears the characteristics of both parents.
A flower is the reproductive organ of a flowering plant. Sex cells are formed in flowers. After pollination and fertilization, fruits with seeds are formed from the flower.
During sexual reproduction, a new organism is formed as a result of the fusion of sex cells (male and female gametes), each of which has its own hereditary characteristics, they are transmitted by chromosomes located in the nuclei of cells. As a result of the recombination of traits, a plant may develop new properties that will help it better adapt to its environment.
In many algae and all higher plants, there is a natural change from asexual reproduction to sexual reproduction.