Chapter 9, Problem 4P

Summary Introduction

To explain:

The physical relationship between sarcoplasmic reticulum and transverse tubules.

Introduction:

Striated muscle fiber is composed of numerous muscles known as muscle fibers. Muscle fibers are the multinucleated elongated cylinder structures attached with connective tissues to form muscles. They are composed of sarcoplasm that contains a long parallel structure known as myofibril that serves as an important component for muscle contraction.

Myofibrils contain filament proteins such as thick filament proteins known as myosin and thin filament proteins known as actin. Their repeated arrangement form sarcomere is responsible for striation in the skeletal muscle fibers.

The myofibril is surrounded by the network of a membranous channel known as sarcoplasmic reticulum. Along with sarcoplasmic reticulum, the membranous channel also forms transverse tubules that invaginate into sarcoplasmic reticulum and contain extracellular fluid.