Final answer:
Curare inhibits depolarization in muscle cells by preventing chemically-gated ion channels from opening, which is essential for an action potential, leading to muscle relaxation and paralysis.
Step-by-step explanation:
When Curare prevents chemically-gated channels from opening, it inhibits the processes necessary for muscle contraction. Specifically, Curare disrupts the depolarization of muscle cells. Depolarization occurs when acetylcholine, a neurotransmitter, binds to receptors on the muscle cell and allows positively charged ions to flow in, altering the electrical charge across the cell membrane. If depolarization does not reach the threshold level of -55mV, an action potential necessary for muscle contraction will not occur. Consequently, without depolarization, there is no subsequent repolarization or hyperpolarization, preventing the muscle fiber from returning to a resting state and making it unresponsive to further nerve impulses. This leads to muscle relaxation and paralysis.
Figure 35.9 illustrates how voltage-gated ion channels normally open in response to changes in membrane voltage, and Figure 26.9 demonstrates the same principle. When Curare is involved, these processes are disrupted, preventing normal muscle function.