Question

Bacteria that cause tetanus release a neurotoxin called tetanospasmin. Which of the following components of the neuromuscular junction (NMJ) does this neurotoxin affect directly?

1) Motor neuron
2) Synaptic cleft
3) Motor end plate
4) Muscle fiber

Answer 1

The neurotoxin tetanospasmin affects the motor end plate directly in the neuromuscular junction.

Step-by-step explanation:

The neurotoxin tetanospasmin, produced by the bacteria that cause tetanus, affects the motor end plate directly. The motor end plate is the location of the acetylcholine (ACh) receptors on the muscle fiber sarcolemma. When ACh molecules are released from the axon terminals, they bind to the receptors at the motor end plate, initiating muscle contraction.