What is the life cycle of Pteridophytes?
The life cycle of pteridophytes is a continuous reproductive process that is dominated by the sporophyte (sexual) stage of the alternation of generations. Fern spores are catapulted into the air, and the spores develop into heart-shaped haploid gametophytes that contain both male and female sex organs.
What is Apomictic development?
Apomixis, or asexual seed formation, is an alternative way to sexual reproduction that some plants use to produce viable seeds containing genetic clones of the female parent. Although it is regarded as a promising tool for breeders and farmers, apomixis does not occur in most food crops.
What is Apomictic line?
Development of Pure Lines: Apomixis is a means of rapid production of pure lines in plants. Haploid apogamy and parthenogenesis give rise to haploid plants which after being treated by colchicine treatment can produce diploid pure lines.
How are Apomictic seeds formed?
Apomixis (asexual seed formation) is the result of a plant gaining the ability to bypass the most fundamental aspects of sexual reproduction: meiosis and fertilization. Without the need for male fertilization, the resulting seed germinates a plant that develops as a maternal clone.
What is the unique character of life cycle of pteridophytes?
Pteridophytes show alternation of generations. Their life cycle is similar to seed-bearing plants, however, the pteridophytes differ from mosses and seed plants as both haploid gametophyte and diploid sporophyte generations are independent and free-living.
Which phase is dominant in the life cycle of pteridophytes?
sporophyte
Zygote or fertilized egg experiences mitotic division forming the different segments such as roots, stem, sporophyte and later on spores, which are again formed via meiosis and dispersed and hence the cycle goes on. Thus, the dominant phase is sporophyte in pteridophytes.
What are apomictic genes?
How does apomictic embryos are formed?
Apomictic processes mimic many of the events of sexual reproduction and give rise to fertile seeds. An important differ- ence is that the apomictic embryo is derived solely from cells in the maternal ovule tissues rather than from the fusion of male and female gametes.
What is apomictic population?
Populations of apomicts are often polyclonal with some clones being geographically widespread. For example the same dandelion apomictic clone was found in the Netherlands and in Denmark, spanning a distance of more than 600 km (Van Dijk et al., 2009).
What is apomictic embryo sac?
Apomixis: Embryo Sacs and Embryos Formed without Meiosis or Fertilization in Ovules.
What are the four characteristics of pteridophytes?
The general characteristics of Pteridophytes are:
- They are seedless.
- They are multicellular.
- They reproduce through spores.
- They are independent and free-living organisms.
- They have a well-differentiated plant body into root, stem and leaves.
What is the characteristics of pteridophytes?
Primary characteristics of Pteridophytes are as follows: They are seedless, vascular plants that show true alternation of generations. Furthermore, the sporophyte has true roots, stems and leaves. They reproduce by spores, which are developed in sporangia. They may be homosporous or heterosporous.
What is the life cycle of pteridophytes?
The life cycle of pteridophytes is a continuous reproductive process that is dominated by the sporophyte (sexual) stage of the alternation of generations. Fern spores are catapulted into the air, and the spores develop into heart-shaped haploid gametophytes that contain both male and female sex organs.
Do pteridophytes show alternation of generations?
Pteridophytes show alternation of generations. Their life cycle is similar to seed-bearing plants, however, the pteridophytes differ from mosses and seed plants as both haploid gametophyte and diploid sporophyte generations are independent and free-living. The sexuality of pteridophytic gametophytes can be classified as follows:
How do Pteridophytes differ from seed-bearing plants?
Their life cycle is similar to seed-bearing plants, however, the pteridophytes differ from mosses and seed plants as both haploid gametophyte and diploid sporophyte generations are independent and free-living. The sexuality of pteridophytic gametophytes can be classified as follows:
What is the sexuality of pteridophytic gametophytes?
The sexuality of pteridophytic gametophytes can be classified as follows: Dioicous: the individual gametophyte is either a male producing antheridia and sperm or a female producing archegonia and egg cells. Monoicous: every individual gametophyte may produce both antheridia and archegonia and it can function both as a male as well as a female.