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A boa constrictor in the U.K. gave birth to 14 babies — without a mate. The process is called parthenogenesis, from the Greek words for “virgin” and “birth.” It tends to occur in ...
Through this research, we gained a lot of knowledge about interspecific pregnancy, specifically what causes it to succeed and fail. [5] Researchers believe that success depends upon the binding of sperm to an oocyte. [5] Without this successful binding, pregnancy failure is more likely to occur after interspecies embryo transmission. [5]
Parthenogenesis can occur without meiosis through mitotic oogenesis. This is called apomictic parthenogenesis. Mature egg cells are produced by mitotic divisions, and these cells directly develop into embryos. In flowering plants, cells of the gametophyte can undergo this process. The offspring produced by apomictic parthenogenesis are full ...
The term is also used in the context of third-party insemination, where a male who is not the woman's usual sexual partner (i.e., a sperm donor) fathers a child for the woman by providing his sperm through sexual intercourse rather than by providing his sperm for it to be used to produce a pregnancy in the woman by artificial means. [10]
Sperm cells can live inside a female's body for up to five days, and once ovulation occurs, the egg remains viable for 12–48 hours before it begins to disintegrate. [4] Superfecundation most commonly happens within hours or days of the first instance of fertilization with ova released during the same cycle.
Sperm storage organs in the fruit fly Drosophila melanogaster.Female was first mated with GFP-male and then re-mated with RFP-male. Female sperm storage is a biological process and often a type of sexual selection in which sperm cells transferred to a female during mating are temporarily retained within a specific part of the reproductive tract before the oocyte, or egg, is fertilized.
In mammals, pregnancy is the period of reproduction during which a female carries one or more live offspring from implantation in the uterus through gestation. It begins when a fertilized zygote implants in the female's uterus , and ends once it leaves the uterus.
The sperm whale or cachalot [a] (Physeter macrocephalus) is the largest of the toothed whales and the largest toothed predator.It is the only living member of the genus Physeter and one of three extant species in the sperm whale family, along with the pygmy sperm whale and dwarf sperm whale of the genus Kogia.