KROK 1 2023 – Question 74 · KROK (Medicine) · Physiology
In an experiment, a neuromuscular preparation of frog was treated with a curare-like substance. As a result, muscle contractions in response to electrical stimulation of the nerve disappeared. What function of the muscle cell membrane is disrupted by curare-like drugs?
- A. Reception of mediators in the neuromuscular synapse
- B. Creating a barrier between the intracellular environment and the surrounding intercellular fluid
- C. Creation of electric potentials on both sides of the membrane
- D. Maintenance of the internal cellular structure, its cytoskeleton
- E. Maintenance of different permeability for different substances
Hint
The nerve still releases its transmitter normally and the muscle fibre itself stays excitable by direct stimulation, so decide which of the listed membrane functions is specific to the nerve-muscle junction.
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