A researcher investigates the effects of aggregate formation on nerve cell function in Alzheimer's. Which mechanism explains why intracellular tau protein aggregates impair axonal transport in neurons?

💡 Explanation

Tau protein aggregates physically block microtubule tracks within the axon, disrupting the transport of organelles and nutrients. Because axonal transport relies on clear microtubule pathways, the aggregate obstructions directly impede it. Therefore, axonal transport is impaired, rather than myelin degradation, ATP production, or ribosome synthesis.

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