Problem:

Question 1: The pH of the lysosome (lumen) is

(a) 7

(b) 6

(c) 5

(d) 4

Question 2: Patients with I-cell disease have non-functional lysosomes. Why?

(a) Acid hydrolases in the lysosome contain mutations that render them functionally inactive.

(b) The pH of the lysosome is not acidic enough.

(c) Acid hydrolases are secreted rather than targeted to the lysosome.

(d) The pH of the lysosome is too acidic.

Provide the correct answer and justification for your choice.