Chapter 9, Problem 3PI

Summary Introduction

To determine: Whether the ACh receptor channel is equally permeable to Na⁺ and K⁺, and the reason why Na⁺ influx dominate.

Introduction: During skeletal muscle contraction, a motor neuron stimulates the skeletal muscle fibers. The stimulation of skeletal muscle fibers ultimately causes the interaction between the myofilaments within the skeletal muscle fibers to produce a surface tension between the muscles. Acetylcholine in the synaptic cleft is hydrolyzed by the enzyme acetylcholinesterase. The receptors for ACh close, and the action potential along with the sarcolemma and T-tubules will cease.