Question

Post mating isolating mechanism includes

• A. Gametic mortality
• B. Zygotic mortality
• C. Hybrid sterility
• D. All of the above

Answer 1

The correct option is D All of the above

Postmating isolating mechanism is any structure, physiological function, or developmental abnormality that prevents organisms of two different populations, once mating has occurred, from producing vigorous, fertile offspring. Postmating isolating mechanisms includes, gametic. Gametic incompatibility (Sperm transfer takes place, but egg is not fertilized), Zygotic mortality (Egg is fertilized, but zygote does not develop), Hybrid inviability (Hybrid embryo forms, but of reduced viability), Hybrid sterility (Hybrid is viable, but resulting adult is sterile) and Hybrid breakdown (First generation (F${}_1$) hybrids are viable and fertile, but further hybrid generations (F${}_2$ and backcrosses) may be inviable or sterile). Thus, option D is correct and other options are wrong.