Agamospermy occurs mainly in two forms: In gametophytic apomixis, the embryo arises from an unfertilized egg cell ( i. e. by parthenogenesis ) in a gametophyte that was produced from a cell that did not complete meiosis.

Algae exhibit a wide range of reproductive strategies, from simple, asexual cell division to complex forms of sexual reproduction.

Most members have a complex life-cycle, involving both asexual and sexual reproduction.

Current hypotheses suggest that asexual reproduction may have short term benefits when rapid population growth is important or in stable environments, while sexual reproduction offers a net advantage by allowing more rapid generation of genetic diversity, allowing adaptation to changing environments.

Most species show cyclical parthenogenesis, where asexual reproduction is occasionally supplemented by sexual reproduction, which produces resting eggs that allow the species to survive harsh conditions and disperse to distant habitats.

** Microevolution: species — speciation — adaptation — selection — natural selection — directional selection — sexual selection — genetic drift — sexual reproduction — asexual reproduction — colony — allele frequency — neutral theory of molecular evolution — population genetics — Hardy-Weinberg principle

Others are capable of asexual reproduction, or sometimes, both methods of reproduction.

The known methods of reproduction are broadly grouped into two main types: sexual and asexual.

In asexual reproduction, an individual can reproduce without involvement with another individual of that species.

The division of a bacterial cell into two daughter cells is an example of asexual reproduction.

The most common mode of vegetative growth in yeast is asexual reproduction by budding.

Both asexual and sexual reproduction can be found in Sipunculans, although asexual reproduction is uncommon.

The more notably distinct trait, which most echinoderms have, is their remarkable powers of regeneration of tissue, organs, limbs, and of asexual reproduction, and in some cases, complete regeneration from a single limb.

Some of these actively break off their arms for the purpose of asexual reproduction.

In at least some of these species, they actively use this as a method of asexual reproduction.

The larvae of some echinoderm species are capable of asexual reproduction.

Some specimens of Cloudina hartmannae display budding, which implies asexual reproduction.

It is a form of asexual reproduction limited to animals or plants of relatively simple structure.

Mammals are now the only major vertebrate group in which asexual reproduction has not been observed.

An asexual colony includes both somatic ( vegetative ) cells, which do not reproduce, and gonidia near the posterior, which produce new colonies through repeated division.

In flowering plants, the term " apomixis " is commonly used in a restricted sense to mean agamospermy, i. e. asexual reproduction through seeds.

After the feeding stage, the trophozoite undergoes asexual replication through longitudinal binary fission.

A life cycle is a period involving all different generations of a species succeeding each other through means of reproduction, whether through asexual reproduction or sexual reproduction ( a period from one generation of organisms to the same identical ).

Hydra may reproduce sexually, through the spawning of sperm ( and thus insemination of eggs on the female body column ), or through asexual reproduction ( budding ).

Reproduction is through a form of asexual ' budding ', in which a smaller, stub cube is left behind in a side corridor to grow into a full-sized cube, although these stub cubes run the risk of being absorbed by their own parent on its next trip down the corridor.

In some plants, the diploid tissue of the nucellus can give rise to a seed through a mechanism of asexual reproduction called nucellar embryony.

The Hyperboreans were asexual and reproduced through " plasmic emanations " from their ethereal bodies ; the Vril power was theirs to command, the light of the Black Sun coursed through their veins and they saw with the Third Eye.

Although the exact nature of the infectious propagule is unknown, the leading hypothesis is the basidiospore created through sexual or asexual reproduction.

All Dralasite go through male, female and asexual stages during their lives.

Doliolids alternate through sexual and asexual generations.

In 2008, a whitetip reef shark produced a single pup through possibly asexual means at the Nyiregyhaza Centre in Hungary ; previous instances of asexual reproduction in sharks have been reported in the bonnethead ( Sphyrna tiburo ) and the blacktip shark ( Carcharhinus limbatus ).

In many cases, isogamous fertilization is used by organisms that can also reproduce asexually through binary fission, budding, or asexual spore formation.

Wright argues that Warren's inspiration of terror through a distorted representation of the uterus strikes a chord with the 1979 film The Brood, in which a woman produces deformed children through asexual reproduction.

Inside the snail, the larva undergo asexual reproduction through a series of stages called sporocysts.

In man: exoerythrocytic stage ( in the liver ): The sporozoites are injected into humans when the mosquito bites and they travel to the liver through blood stream and undergo asexual reproduction to become merozoites through schizonts in the liver cell.

In Pilosella, many individual plants are capable of forming both normal sexual and asexual ( apomictic ) seeds, whereas individual plants of Hieracium only produce one kind of seeds.

Apomixis ( asexual reproduction from non-fertilized seeds ) appeared common in P. orientalis.

No males have been found of one species of this genus which does flower and produce seeds, and it is commonly called, the Mother of Thousands ; the Kalanchoe daigremontiana is thus an example of asexual reproduction ( not so common for leaves ).

Therefore, propagation via asexual seeds or apomixis is asexual reproduction but not vegetative propagation.

Vertically transmitted fungal endophytes are asexual and transmit via fungal hyphae penetrating the host ’ s seeds ( e. g. Neotyphodium ).

These endophytes are asexual, seed-borne symbionts of cool-season grasses, and grow intercellularly throughout the aerial tissues of their hosts, including shoot apical meristems, leaf sheaths and blades, inflorescences, seeds and embryos.

* A few plant species can form colonies via asexual seeds, termed apomixis, e. g. dandelion.