cloacal copulation is the type of reproduction that requires the union of sperm and egg.
cloacal copulation is the type of reproduction that requires the union of sperm and egg.
the type of reproduction that requires the union of sperm and egg?
cloacal copulation
emily martin examines the metaphors used in science to support her claim that science reinforces socially constructed ideas about gender rather than objective views of nature. in her study about the fertilization process, martin describes several cases when gender-biased perception skewed the descriptions of biological processes during fertilization and even possibly hampered the research. she asserts that classic metaphors of the strong dominant sperm racing to an idle egg are products of gendered stereotyping rather than a faithful portrayal of human fertilization. the notion that women are passive and men are active are socially constructed attributes of gender which, according to martin, scientists have projected onto the events of fertilization and so obscuring the fact that eggs do play an active role. for example, she wrote that "even after having revealed...the egg to be a chemically active sperm catcher, even after discussing the egg's role in tethering the sperm, the research team continued for another three years to describe the sperm's role as actively penetrating the egg." scott gilbert, a developmental biologist at swarthmore college supports her position: "if you don’t have an interpretation of fertilization that allows you to look at the egg as active, you won’t look for the molecules that can prove it. you simply won’t find activities that you don’t visualize."
criticism of science
the female pronucleus is the female egg cell once it has become a haploid cell, and the male pronucleus forms when the sperm enters into the female egg. while the sperm develops inside of the male testes, the sperm does not become a pronucleus until it decondenses quickly inside of the female egg. when the sperm reaches the female egg, the sperm loses its outside membrane as well as its tail. the sperm does this because the membrane and the tail are no longer needed by the female ovum. the purpose of the cell membrane was to protect the dna from the acidic vaginal fluid, and the purpose of the tail of the sperm was to help move the sperm cell to the egg cell. the formation of the female egg is asymmetrical, while the formation of the male sperm is symmetrical. typically in a female, meiosis starts with one diploid cell and becomes one ovum and three polar bodies. in a male, meiosis starts with one diploid cell and ends with four sperm. in mammals, the female pronucleus starts in the center of the egg before fertilization. when the male pronucleus is formed, after the sperm cell reaches the egg, the two pronuclei migrate towards each other. however, in brown alga pelvetia, the egg pronucleus starts in the center of the egg before fertilization and remain in the center after fertilization. this is because the egg cells of brown alga pelvetia, the egg pronucleus is anchored down by microtubules so only the male pronucleus migrates towards the female pronucleus.
pronucleus