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Asexual reproduction is a type of reproduction that does not involve the fusion of gametes or change in the number of chromosomes. The offspring that arise by asexual reproduction from either unicellular or multicellular organisms inherit the full set of genes of their single parent and thus the newly created individual is genetically and ...
This is an asexual form of reproduction that is only found in females of some insects, crustaceans, nematodes, [24] fish (for example the hammerhead shark [25]), Cape honeybees, [26] and lizards including the Komodo dragon [25] and several whiptails. The growth and development occurs without fertilization by a male.
The cloning of an organism is a form of asexual reproduction. By asexual reproduction, an organism creates a genetically similar or identical copy of itself. The evolution of sexual reproduction is a major puzzle for biologists. The two-fold cost of sexual reproduction is that only 50% of organisms reproduce [1] and organisms only pass on 50% ...
A female produces an ovum with a full set (two sets of genes) provided solely by the mother. Thus, a male is not needed to provide sperm to fertilize the egg. This form of asexual reproduction is thought in some cases to be a serious threat to biodiversity for the subsequent lack of gene variation and potentially decreased fitness of the offspring.
Agamospermy, asexual reproduction through seeds, occurs in flowering plants through many different mechanisms [4] and a simple hierarchical classification of the different types is not possible. Consequently, there are almost as many different usages of terminology for apomixis in angiosperms as there are authors on the subject.
However, these eukaryotes probably are not primitively asexual, but have lost their sexual reproduction, or it just was not observed yet. [27] [28] Many eukaryotes (including animals and plants) exhibit asexual reproduction, which may be facultative or obligate in the life cycle, with sexual reproduction occurring more or less frequently. [29]
Initially, Adelbert von Chamisso (studying salps, colonial marine animals between 1815 and 1818 [10]) and Japetus Steenstrup (studying the development of trematodes in 1842, and also tunicates and cnidarians) described the succession of differently organized generations (sexual and asexual) in animals as "alternation of generations". [11]
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 ...