Here are the answers to your questions:Sexual reproduction: Takes place when sex cells of two parent animals unite to form a new organism.Gametes: Another term for sex cells.Internal fertilization: Fertilization that happens when sperm cells are released into the body of the female animal.Fish (e.g., salmon) or amphibians (e.g., frogs): Examples of animals that undergo external fertilization.Sperm: The sex cell of a male animal.Egg (or ovum): The sex cell of a female animal.Zygote: Another term for a fertilized egg.External fertilization: Fertilization that takes place when the union of the sex cells happens outside the body.Let me know if you need more information!