What determines whether a respiratory system structure is part of the respiratory zone, and not part of the conducting zone?

During which phase does earth see more than half of the moon's surface? 1)first quarter2)third quarter3)waxing gibbous4)waning crescent

Which type of respiration takes place when there is no oxygen present

The image shows the evolution of a species of fish. a few fish from a population developed different social behaviors and evolved into different species. two fish according to the image, the fish underwent . the new species of fish had mating seasons that were different from that of the original fish. because of the differences in mating seasons, the fish underwent reproductive isolation. this mode of isolation would be .