The Lungs Deliver a Regular Supply of Oxygen to the Blood

Multiple Choice

The lungs deliver a regular supply of oxygen to the blood, which is in turn circulated to most all the cells of the body. At the same time oxygen is consumed during aerobic cellular respiration within these cells. This implies that _________.

A) the rate of oxygen diffusion is independent of concentration
B) the concentration gradient for oxygen is steepness inside of the cell
C) oxygen will passively diffuse into the cells
D) oxygen requires active transport to enter most cells