AP BIOLOGY

Detailed explanation-1: -Prezygotic barriers prevent members of different species from mating to produce a zygote, a single-celled embryo. Some example scenarios are below: Two species might prefer different habitats and thus be unlikely to encounter one another. This is called habitat isolation.

Detailed explanation-2: -Barriers to reproduction can be effective before and after the formation of a zygote. Prezygotic barriers include spatial or temporal separation of reproduction as well as behavioural differences leading to sexual isolation.

Detailed explanation-3: -Answer and Explanation: A reproductive barrier that prevents species from mating is an example of a prezygotic barrier. The mechanism by which mating is prevented before fertilization and zygote formation is called the prezygotic mechanism.

Detailed explanation-4: -There are two main categories of reproductive isolation barriers: Prezygotic isolation – occurs before fertilisation can occur (no offspring are produced) Postzygotic isolation – occurs after fertilisation (offspring are either not viable or infertile)

Detailed explanation-5: -As mentioned above, postzygotic reproductive barriers are those that occur after fertilization. These barriers occur after a zygote has formed and reduce the viability or fitness of hybrid zygotes or offspring. Some examples include: Hybrid sterility: Mules are the hybrid offspring of horses and donkeys.