Final answer:
Reproductive isolation involves biological factors known as prezygotic and postzygotic barriers that prevent different species from producing viable, fertile offspring. It includes gametic and temporal isolation as well as hybrid inviability and sterility.
Step-by-step explanation:
Biological Barriers in Reproductive Isolation
The existence of biological factors that prevent members of two different species from interbreeding and producing viable, fertile offspring is known as reproductive isolation. This process can be divided into two categories: prezygotic barriers and postzygotic barriers. Prezygotic barriers inhibit reproduction attempts before the formation of a zygote, such as gametic barriers where gamete cells are incompatible, and temporal isolation due to differences in breeding times. Postzygotic barriers occur after zygote formation, leading to issues such as hybrid inviability, where the hybrid organism cannot survive past embryonic stages, or hybrid sterility, where the hybrid is incapable of reproducing.