Download - Thursday October 22, 2009
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Thursday October 22, 2009
Pick up the muscle note sheet!
Did you miss the test on Tuesday?
Did you complete virtual surgery? COOL!
The Man Whose Arms Exploded
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Agenda & Homework
Agenda:
1) Cadaver visits December 8 & 10, 2009
2) Muscle Physiology
3) Muscle Anatomy
Homework:
Learning muscles by making flash cards
Use the website to study muscles
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Muscle Overview
The three types of muscle tissue are skeletal, cardiac, and smooth
These types differ in structure, location, function, and means of activation
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Muscle Tissue: Cardiac
Figure 4.11b
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Muscle Tissue: Smooth
Figure 4.11c
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Muscle Tissue: Skeletal
Long, cylindrical, multinucleate cells with obvious striations
Initiates and controls voluntary movement
Found in skeletal muscles that attach to bones or skin
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Muscle Tissue: Skeletal
Figure 4.11a
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Skeletal Muscle Tissue
Packaged in skeletal muscles that attach to and cover the bony skeleton
Has obvious stripes called striations
Is controlled voluntarily (i.e., by conscious control)
Contracts rapidly but tires easily
Is responsible for overall body motility
Is extremely adaptable and can exert forces ranging from a fraction of an ounce to over 70 pounds
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Skeletal Muscle
Skeletal muscle cells are elongated and are called muscle fibers
Muscle contraction depends on two kinds of myofilaments (proteins) – actin and myosin
Muscle terminology
Sarcolemma – muscle cell membrane
Sarcoplasm – cytoplasm of a muscle cell
Prefixes – myo, mys, and sarco all refer to muscle
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Muscle Function
1) Skeletal muscles are responsible for all locomotion
2) Muscles also maintain posture, stabilize joints, and generate heat (ex: shiver)
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Structure and Organization of Skeletal Muscle
Table 9.1a
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Structure and Organization of Skeletal Muscle
Table 9.1b
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Skeletal Muscle
Each muscle is a discrete organ composed of muscle tissue, blood vessels, nerve fibers, and connective tissue
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Skeletal Muscle
The three connective tissue sheaths are:
Endomysium – fine sheath of connective tissue composed of reticular fibers surrounding each muscle fiber (cell)
Perimysium – fibrous connective tissue that surrounds groups of muscle fibers called fascicles
Epimysium – an overcoat of dense regular connective tissue that surrounds the entire muscle
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Skeletal Muscle
Figure 9.2a
Circle the Endomysium,Perimysium & Epimysium
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Nerve and Blood Supply
Each muscle is served by one nerve, an artery, and one or more veins
Each skeletal muscle fiber is supplied with a nerve ending that controls contraction
Contracting fibers require continuous delivery of oxygen and nutrients via arteries
Wastes must be removed via veins
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Skeletal Muscle: Attachments
Muscles attach:
1. Directly – epimysium of the muscle is fused to the periosteum of a bone
2. Indirectly – connective tissue wrappings extend beyond the muscle as a tendon or aponeurosis
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
LEARN THE MUSCLES!