Membrane-Bound Organelles and Compartmentalization (2A) Practice Test

A neuronal cell model was exposed to a mitochondrial uncoupler that dissipates the proton gradient across the inner mitochondrial membrane. Mitochondria are membrane-bound organelles that generate ATP via oxidative phosphorylation. Within 30 minutes, cellular ATP levels fell and cytosolic AMP increased, while oxygen consumption transiently rose. Which outcome best exemplifies the role of mitochondria in this scenario?

A cell biologist tracked a fluorescently labeled lysosomal enzyme precursor synthesized in the RER. Lysosomal enzymes are typically tagged in the Golgi for sorting to lysosomes rather than secretion. In cells lacking the Golgi enzyme that adds the lysosome-targeting carbohydrate tag, the labeled precursor was detected in the extracellular medium. Which outcome best exemplifies the role of the Golgi in this scenario?