Question

In a laboratory experiment, adding curare, which binds to acetylcholine receptors, to the solution around a muscle decreases the size of the end-plate potential. Adding prostigmine, an acetylcholinesterase blocker, increases the size of the end-plate potential. Explain why.

Answer 1

Curare blocks acetylcholine receptors, causing muscle relaxation. Prostigmine inhibits acetylcholinesterase, increasing acetylcholine availability and enhancing muscle contraction.

Step-by-step explanation:

The size of the end-plate potential can be affected by the presence of curare and prostigmine in a laboratory experiment. Curare is a drug that binds to acetylcholine receptors and blocks the action of acetylcholine. This prevents muscle contraction and leads to muscle relaxation and paralysis. On the other hand, prostigmine is an acetylcholinesterase blocker, which means it inhibits the enzyme that degrades acetylcholine. As a result, more acetylcholine is available to bind to receptors, leading to an increase in the size of the end-plate potential and enhanced muscle contraction.