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Fertilization is the fusion of gametes to produce a new organism. In animals, the process involves a sperm fusing with an ovum, which eventually leads to the development of an embryo. Depending on the animal species, the process can occur within the body of the female in internal fertilization, or outside in the case of external fertilization.
The characteristic quivering abdomen caused by movement of tadpoles within a pregnant female Limnonectes larvaepartus.. 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.
Parental care is seen in many insects, notably the social insects such as ants, bees and wasps; in certain fishes, such as the mouthbrooders; widely in birds; in amphibians; rarely in reptiles and especially widely in mammals, which share two major adaptations for care of the young, namely gestation (development of the embryo inside the mother ...
Parthenogenesis occurs naturally in some plants, algae, invertebrate animal species (including nematodes, some tardigrades, water fleas, some scorpions, aphids, some mites, some bees, some Phasmatodea, and parasitic wasps), and a few vertebrates, such as some fish, amphibians, and reptiles. This type of reproduction has been induced ...
This capsule also prevents the egg from drying out. The vitelline membrane is a membrane surrounding the egg. Upon fertilization, this membrane splits off from the surface of the egg and the space between the vitelline membrane and the embryo is filled with perivitelline fluid. This fluid surrounds the embryo and yolk plug.
The decline in amphibian and reptile populations has led to an awareness of the effects of pesticides on reptiles and amphibians. [177] In the past, the argument that amphibians or reptiles were more susceptible to any chemical contamination than any land aquatic vertebrate was not supported by research until recently. [ 177 ]
There are over 6700 species of amphibians [9] and over 9000 species of reptiles. [10] Despite its modern taxonomic irrelevance, the term has persisted, particularly in the names of herpetology, the scientific study of non-avian reptiles and amphibians, and herpetoculture, the captive care and breeding of reptiles and amphibians.
Fertilization is the fusion of two gametes. [1] Copulation is the union of the sex organs of two sexually reproducing animals for insemination and subsequent internal fertilization. [2] Mating may also lead to external fertilization, as seen in amphibians, fishes and plants. For most species, mating is between two individuals of opposite sexes.