Chapter 4 - Muscle Tissue

Muscle cells (also known as muscle fibers) synthesize and maintain the contractile function of connective tissue. Three types of muscle are recognized based on their distinctive structural and functional features: skeletal, cardiac muscle and smooth muscle.

Skeletal Muscle

Skeletal muscle is composed of long, multinuclear cells with the nuclei located at the periphery of the cell. The cells are striated because of the parallel arrangement of contractile filaments appear as an alternating series of transverse bands.

	EM 222 Skeletal Muscle
	EM 123 Skeletal Muscle

Cardiac Muscle

Cardiac muscle is composed of branched, mononuclear cells (occasionally bi-nucleate) with the nuclei located in the center of the cell. The cells show the same striations as skeletal muscle.

	EM 137 Cardiac Muscle
	EM 122 Cardiac Muscle
	EM 133 Cardiac Muscle

Smooth Muscle

Smooth muscle contains the same contractile proteins as skeletal and cardiac muscle, but the less ordered array of contractile filaments does not produce striations.

	EM 236 Smooth Muscle Cell
	EM 132 Smooth Muscle Cell
	EM 121 Smooth Muscle Cells
	EM 126 Smooth Muscle