NEET2026BiologyChapterActual
If the membrane of a lysosome accidentally ruptures and releases its hydrolytic enzymes into the surrounding cytosol (which has a near-neutral pH), the cell is usually not destroyed. What is the primary reason for this?
Options
- AThe enzymes require an acidic pH for optimal activity and become largely inactive in the neutral cytosol.
- BThe enzymes are immediately targeted to the proteasome for degradation by cytosolic proteins.
- CThe hydrolytic enzymes require a continuous supply of ATP to function, which is unavailable in the cytosol.
- DThe enzymes are quickly re-packaged into new vesicles by the endoplasmic reticulum.
Correct answer
A. The enzymes require an acidic pH for optimal activity and become largely inactive in the neutral cytosol.
Step-by-step solution
Lysosomes contain hydrolytic enzymes known as acid hydrolases, which function optimally at an acidic pH of approximately 4.5 to 5.0 . The cytosol of a cell has a near-neutral pH of about 7.2 . If a lysosome accidentally ruptures and releases its contents into the cytosol, the hydrolytic enzymes are exposed to this neutral environment. Because their optimal activity requires an acidic pH, they become largely inactive in the cytosol. This pH dependence serves as a protective mechanism for the cell, preventing the enz