[Campbell Biology P.1130] Botulinum toxin, known by the trade name Botox, is used cosmeticall... | Practice Question

Botulinum toxin, known by the trade name Botox, is used cosmetically to minimize wrinkles. Based on the provided text, what is its mechanism of action regarding acetylcholine?

  • A: It enhances the release of acetylcholine (ACh), leading to muscle spasms.
  • B: It blocks acetylcholine (ACh) receptors on muscle cells, causing muscle paralysis.
  • C: It inhibits the presynaptic release of acetylcholine (ACh), leading to muscle paralysis.
  • D: It breaks down acetylcholine (ACh) in the synapse, enhancing muscle contraction.

Explanation

The text states that botulinum toxin 'inhibits presynaptic release of acetylcholine.' This prevents muscle contraction, leading to paralysis, which is used cosmetically to relax facial muscles and minimize wrinkles.