The oil layer prevents the entry of air into glucouse explain why is this necssary

What is the difference between the conducting zone and the respiratory zone of the respiratory system? the conducting zone is a series of cavities and tubes that move air to the respiratory zone where gases exchange with the bloodstream. the conducting zone exchanges gases between the lungs and the alveoli and the respiratory zone is a series of cavities and tubes that move air to the conducting zone. the conducting zone moves oxygen into the cells and the respiratory zone takes carbon dioxide away from the cells. the conducting zone moves oxygen into the bloodstream and the respiratory zone takes carbon dioxide away from the bloodstream.

Astudent analyzed ears of corn that demonstrated two traits in the f2 kernels, purple or white colors and smooth on wrinkled shapes. a tabulation of 135 individual kernels gave the following results: purple and smooth = 75 white and smooth = 28 purple and wrinkled = 24 white and wrinkled = 8 what would be the only phenotype present in the f1 ger

In general, characteristics that an organism survive and reproduce become more common over time. what mechanism of evolution causes this?