Question 2: is the primary mechanism of action of tetanus toxin (Clostridium tetani)? A. Inhibits the release of acetylcholine at the neuromuscular junction B. Blocks the release of inhibitory neurotransmitters like GABA and glycine C. Causes direct destruction of neurons through enzymatic activity D. Stimulates excessive production of dopamine in the brain

The correct answer is B. Blocks the release of inhibitory neurotransmitters like GABA and glycine.<br /><br />Tetanus toxin, produced by the bacterium Clostridium tetani, primarily acts by blocking the release of inhibitory neurotransmitters such as gamma-aminobutyric acid (GABA) and glycine at the neuromuscular junction. This inhibition prevents the relaxation of muscles, leading to the characteristic muscle stiffness and spasms seen in tetanus.