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Animals that live in water, such as amphibians and fish, use external fertilization. The term refers to the process by which the egg is fertilized by the sperm in an open environment and not within the bodies of the orga... More »

Disadvantages of external fertilization include a reliance on water and the large amount of wasted sperm and eggs that never reach a corresponding gamete, even when the organisms releasing the eggs and sperm are in close... More »

Examples of external fertilization can be seen in frogs, some marine invertebrates and many types of fish. External fertilization happens when sperm fertilize eggs outside of the body of the female animal. Often, in orde... More »

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