This is due to the fact that there is little food (flying insects) for them to eat. If they stayed awake in a warm home, without hibernating, then they would starve. We can begin the bat exclusion process during the winter months.
Mean free path of molecules in a gas. The molecules in a gas are assumed to be in continuous random motion making collisions with each other and with the walls of the container. The mean distance that the molecules travel between one collision and the next is called the mean free path of the molecules.
Facilitated Diffusion Diffusion is the flow of chemicals and other substances to a region of low concentration from a region of high concentration. Certain small nonpolar substances, such as oxygen, can diffuse directly through the membrane in a process called simple diffusion. Large, polar or charged molecules and ions either cannot squeeze through the small membrane spaces or are repelled by the hydrophobic membrane interior.