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Androgenesis is a system of asexual reproduction that requires the presence of eggs and occurs when a zygote is produced with only paternal nuclear genes.During standard sexual reproduction, one female parent and one male parent each produce haploid gametes (such as a sperm or egg cell, each containing only a single set of chromosomes), which recombine to create offspring with genetic material ...
The process of androgenesis allows a mature plant embryo to form from a reduced, or immature, pollen grain. [20] Androgenesis usually occurs under stressful conditions. [20] Embryos that result from this mechanism can germinate into fully functional plants. As mentioned, the embryo results from a single pollen grain.
Androgenesis occurs when a zygote is produced with only paternal nuclear genes. During standard sexual reproduction , one female and one male parent each produce haploid gametes (such as a sperm or egg cell, each containing only a single set of chromosomes ), which recombine to create offspring with genetic material from both parents.
Androgenesis and androclinesis are synonyms. These terms are used for two different processes that both have the effect of producing an embryo that has "male inheritance". The first process is a natural one. It may also be referred to as male apomixis or paternal apomixis. It involves fusion of the male and female gametes and replacement of the ...
Androgenesis is the preferred method. Another method of producing the haploids is wide crossing. In barley, haploids can be produced by wide crossing with the related species Hordeum bulbosum ; fertilization is affected, but during the early stages of seed development the H. bulbosum chromosomes are eliminated leaving a haploid embryo.
Androgenesis - a form of quasi-sexual reproduction in which a male is the sole source of the nuclear genetic material in the embryo; Telescoping generations; Charles Bonnet – Genevan botanist (1720–1793) – conducted experiments that established what is now termed parthenogenesis in aphids
Androgenesis occurs rarely in the tree of life, with only a few occurrences documented and multiple mechanisms through which it is achieved. In Corbicula, androgenesis occurs through the ejection of maternal chromosomes from the egg following fertilization by sperm. [4]
The first fossilized evidence of sexual reproduction in eukaryotes is from the Stenian period, about 1.05 billion years old. [19] [20]Biologists studying evolution propose several explanations for the development of sexual reproduction and its maintenance.