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Oviparous animals are animals that reproduce by depositing fertilized zygotes outside the body (known as laying or spawning) in metabolically independent incubation organs known as eggs, which nurture the embryo into moving offsprings known as hatchlings with little or no embryonic development within the mother.
Hemotrophic viviparity: nutrients are provided by the female, often through a placenta, as in mammals except for marsupials and monotremes. In the frog Gastrotheca ovifera, embryos are fed by the mother through specialized gills. The lizard Pseudemoia pagenstecheri and most mammals use this form of viviparity. [1]
Ovoviviparity, ovovivipary, ovivipary, or aplacental viviparity is a term used as a "bridging" form of reproduction between egg-laying oviparous and live-bearing viviparous reproduction. Ovoviviparous animals possess embryos that develop inside eggs that remain in the mother's body until they are ready to hatch.
For humans, we're 99.9 percent similar to the person sitting next to us. The rest of those genes tell us everything from our eye color to if we're predisposed to certain diseases.
An aphid giving viviparous birth, an unusual mode of reproduction among insects. In animals, viviparity is development of the embryo inside the body of the mother, with the maternal circulation providing for the metabolic needs of the embryo's development, until the mother gives birth to a fully or partially developed juvenile that is at least metabolically independent.
Human reproduction naturally takes place as internal fertilization by sexual intercourse. During this process, the man inserts his erect penis into the woman's vagina and then either partner initiates rhythmic pelvic thrusts until the man achieves orgasm , which leads to ejaculation of semen containing sperm into the vaginal canal.
An example of an iteroparous organism is a human—humans are biologically capable of having offspring many times over the course of their lives. Iteroparous vertebrates include all birds, most reptiles, virtually all mammals, and most fish. Among invertebrates, most mollusca and many insects (for example, mosquitoes and cockroaches) are ...
Viviparous mammals are in the subclass Theria; those living today are in the Marsupialia and Placentalia infraclasses. A marsupial has a short gestation period, typically shorter than its estrous cycle , and gives birth to an underdeveloped ( altricial ) newborn that then undergoes further development; in many species, this takes place within a ...