Final answer:
Species where every individual has both male and female reproductive structures are termed monoecious in plants, and exhibit sequential hermaphroditism in animals. Protogyny and protandry are terms that describe the order in which sex change occurs in sequential hermaphrodites. Monoecious species have both male and female reproductive organs on the same individual, while dioecious species have them on separate individuals.
Step-by-step explanation:
In biology, species in which every individual has both functional female and male reproductive structures are described using a specific term. These individuals are capable of changing their sex during their lives, which is termed sequential hermaphroditism. When an individual is born female and later becomes male, it is known as protogyny, while the reverse situation, starting as male and becoming female, is termed protandry.
For species with fixed reproductive structures throughout their life, those with both male and female reproductive structures on the same plant or animal are termed monoecious. Examples include corn and pea. On the other hand, species like C. papaya and Cannabis, which have male and female structures on separate individuals, are called dioecious.
Therefore, the best term that describes species where individuals have both functional male and female reproductive organs is monoecious when referring to plants, and sequential hermaphroditism when referring to animals like certain oyster species that can change sex multiple times during their lifespan.