A 70-year-old man has progressive memory loss. Autopsy shows neurofibrillary tangles and extracellular plaques. What is the main component of the plaques?
Answer and explanation
Correct answer: A. Beta-amyloid
- Step 1: Plaques are made of beta-amyloid. Answer: Beta-amyloid. Why not the others: Tau forms the tangles, alpha-synuclein forms Lewy bodies and prion protein causes spongiform change.
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