Final answer:
The concentration of H+ ions would increase as substances move from the small intestine to the large intestine due to the pH dropping from 7.5 to 5.5, which represents a hundred-fold increase in H+ concentration because the pH scale is logarithmic.
Step-by-step explanation:
As substances travel from the small intestines to the large intestine, the concentration of H+ ions could increase. This is because the pH scale is logarithmic, where a decrease in pH value means an increase in acidity, and thus, an increase in the concentration of H+ ions.
The pH of the small intestines is around 7.5 (slightly alkaline), and the pH of the large intestine can be 5.5 (more acidic). Therefore, moving from a pH of 7.5 to 5.5 represents a hundred-fold increase in the concentration of H+ ions due to the inverse logarithmic nature of the pH scale.
It is important to note that the human body has various pH levels in different parts to facilitate various functions. The pH of body fluids plays important roles in digestion, enzyme activity, and maintaining a healthy physiological state.