Which of These is Not Gametic Isolation

Question

Which of these is not gametic isolation?
A) Female stigma destroys germinating pollen grain.
B) Lily sperm cannot fertilize tulip eggs.
C) Pollen grain does not germinate on stigma (female structure).
D) Male and female sex organs do not fit together.

Accepted Answer

Male and female sex organs not fitting together is an example of mechanical isolation, not gametic isolation. Gametic isolation refers specifically to the fact that the gametes (sperm and egg cells) of two species are unable to successfully fertilize each other, even if they do come into contact. Examples of gametic isolation include options A, B, and C.