The concept that states "the rate of diffusion across a membrane is directly proportional to the concentration gradient of the substance on the two sides of the membrane and inversely related to the thickness of the membrane" is referred to as the _______.

Compared to adult hemoglobin, fetal hemoglobin has a _______ affinity for oxygen. Thus, the fetal oxygen dissociation curve exhibits a ________ shift.

The Bohr effect helps ______ oxygen into the tissues because of the _____ partial pressure of carbon dioxide in the metabolically active tissues.