Muscle Tissues Muscle tissues Skeletal (striated) muscle Used to move skeleton Cardiac muscle Intercalated discs Smooth muscle Found in hollow organs and blood vessel walls Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings

Skeletal Muscle Tissue Figure 4.14a Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings

Skeletal Muscle

Skeletal Muscle

Smooth muscle cell Nucleus Smooth muscle APPERANCE: not striated, single nuclei LOCATIONS: Encircles blood vessels; found in walls of hollow organs (digestive tract, etc) FUNCTIONS: Involuntary movement of food, and secretions; control of vessel diameter

Smooth Muscle Tissue Figure 4.14c Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings

Smooth muscle

Smooth Muscle

Smooth Muscle

Cardiac Muscle Tissue Figure 4.14b Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings

Cardiac muscle LOCATIONS: walls of heart (myocardium) APPERANCE: striated with branched cells, single nuclei, and intercalated discs FUNCTIONS: involuntary beating of heart Nucleus Cardiac muscle cells Intercalated discs are made of gap junctions AND desmosomes (like rivets) Intercalated discs Striations Cardiac muscle

Cardiac muscle, longitudinal section

Cardiac Muscle Intercalated discs

Neuromuscular junction Motor neuron Neuromuscular junction axon

NOTE: Each muscle fiber is innervated by only ONE neuron Neuromuscular junction NOTE: Each muscle fiber is innervated by only ONE neuron

V. Muscle Tissue Smooth Skeletal Cardiac Neuromuscular junction

Neuromusclular Junction