Chapter 9.5, Problem 42AYP

Summary Introduction

To analyze:

The contribution of the initial length of the muscle in the actin-myosin overlap and the amount of contraction.

Introduction:

When a skeletal muscle fiber contracts, myosin heads attach to actin to form cross-bridges followed by the thin filaments sliding over the thick filaments as the heads pull the actin, and this results in sarcomere shortening, creating the tension of the muscle contraction. The cross-bridges can only form where thin and thick filaments already overlap so that the length of the sarcomere has a direct influence on the force generated when the sarcomere shortens. This is called the length-tension relationship.