Sexually reproducing organisms are diploid (having two sets of chromosomes, one from each parent). In humans, only their egg and sperm cells are haploid.

Over the course of evolution, the gametophyte stage has become progressively reduced. Thus, the gametophyte stage is dominant in the more primitive (nonvascular) plants (bryophytes), whereas the sporophyte is the dominant phase in the life cycle of higher (i.e., vascular) plants.

Sporophyte phase produces spores, while gametophyte phase produces gametes (egg and sperms). Therefore, sporophyte phase is asexual, while gametophyte phase is sexual. Sporophyte is a diploid phase (2N) due to the formation of zygote, while gametophyte is a haploid phase (N) due to the occurrence of meiosis.

Flowers form on the dominant sporophyte plant. They consist of highly specialized male and female reproductive organs. Flowers produce spores that develop into gametophytes.

Apospory is the development of 2n gametophytes, without meiosis and spores, from vegetative, or nonreproductive, cells of the sporophyte. In contrast, apogamy is the development of 1n sporophytes without gametes and syngamy from vegetative cells of the gametophyte.

plant occurrence In contrast, apogamy is the development of 1n sporophytes without gametes and syngamy from vegetative cells of the gametophyte. Certain other ferns reproduce apogamously in nature; thus, for example, in the holly fern (Crytomium falcatum), the gametophytes give rise directly to sporophytes by…

: development of a sporophyte from a gametophyte without fertilization.

GOEBEL

(iii) Apospory : It is the formation of complete embryo sac from the sporophytic cell without meiosis so that the gametophyte remains diploid.

Apospory (Definition)- Apospory is the process of formation of the diploid gametophyte (2n) from the vegetative cells of the sporophyte (2n), without meiosis and formation of spores. It was first discovered in the year 1884 by Druery, in the plant Athyrium foemina var. clarissima jones.

Alternation of generations, also called metagenesis or heterogenesis, in biology, the alternation of a sexual phase and an asexual phase in the life cycle of an organism. The two phases, or generations, are often morphologically, and sometimes chromosomally, distinct.

Answer: The correct answer is 3) A gametophyte is a haploid phase. Alternation of generation is a type of sexual life cycle that is found in all plants and some algae. In these organisms, a multicellular gametophyte that is haploid phase alternates with a multicellular sporophyte, which is a diploid phase.

Bryophyte Generations Like all plants, the bryophyte life cycle goes through both haploid (gametophyte) and diploid (sporophyte) stages. The gametophyte comprises the main plant (the green moss or liverwort), while the diploid sporophyte is much smaller and is attached to the gametophyte.

Heteromorphic alternation of generations means that there is a sporophyte version of the plant and a gametophyte version of the plant that each participate in that plant species’s life cycle. The gametophyte plant (or plants) make the gametes. That’s right a perfect, beautiful sporophyte zygote.

Species with heteromorphic life cycle have a large multicellular body in one generation but have a microscopic body in the other generation of a year. In contrast, isomorphic species have both diploid and haploid life forms with very similar morphology, having more than two generations in a year.

1 : deviating from the usual form. 2 : exhibiting diversity of form or forms heteromorphic pairs of chromosomes.

Haploid cells undergo mitosis to produce a gametophyte. The gametophyte produces haploid gametes which fuse to form a diploid zygotic sporophyte. Alternation of generations is a reproductive cycle of certain vascular plants, fungi, and protists.

Alternation of generations is defined as the alternation of multicellular diploid and haploid forms in the organism’s life cycle, regardless of whether or not these forms are free-living. The free-swimming, haploid gametes form a diploid zygote which germinates into a multicellular diploid sporophyte.

The alternation of generations allows for both the dynamic and volatile act of sexual reproduction and the steady and consistent act of asexual reproduction. When the sporophyte creates spores, the cells undergo meiosis, which allows the gametophyte generation to recombine the genetics present.

Spores are usually haploid and unicellular and are produced by meiosis in the sporangium of a diploid sporophyte. Under favourable conditions the spore can develop into a new organism using mitotic division, producing a multicellular gametophyte, which eventually goes on to produce gametes.

(a) Heteromorphic system: In this type of incompatibility same species produce more than one morphological type of flowers. For example relative length of styles and stamens in flowers of same species. Distyly and tristyly (Fig. 2.37) has been reported in Primula and Evening primrose respectively.

Mosses reproduce by spores, which are analogous to the flowering plant’s seed; however, moss spores are single celled and more primitive than the seed. Mosses also spread asexually by sending out new shoots in the spring from last years plants as well as fragmentation.

gametophyte

The life cycle of a moss, like all plants, is characterized by an alternation of generations. A diploid generation, called the sporophyte, follows a haploid generation, called the gametophyte, which is in turn followed by the next sporophyte generation.

If soil particles can be carried such distances then so could spores and other propagules of a variety of organisms, including bryophytes. Indeed, it has been estimated that spores with diameters up to 12 micrometres would be capable of carried over 12,000 kilometres by wind.

The life cycle of most mosses begins with the release of spores from a capsule, which opens when a small, lidlike structure, called the operculum, degenerates. A single spore germinates to form a branched, filamentous protonema, from which a leafy gametophyte develops.

Yes, moss is both a decomposer and a producer. It is a decomposer because it has the ability to break down organic matter and release certain…