1. Chapter 6
The Muscular System

2. I.Overview of Muscle Tissues
Differ in cell structure,location, and how they are stimulated to contract
Smooth and skeletal muscle cells are elongated and called ________________________
Contraction-shortening-depends on 2 types of myofilaments
Terms myo-,sarco- and mys- refers to muscle-example-muscular cytoplasm is called ___________________.
Muscle fibers
sarcoplasm

3. skeletal muscle attach to skeleton and form smoother contours of body
huge,cigar shaped and ______________________
largest of muscle fibers-as much as 30 cm in length
__________________________with obvious stripes
___________________since only muscle subject to conscious control
Voluntary muscle
multinucleate
striated

4. However,subject to involuntary reflexes
Tire easily and requires rest
Fairly fragile
Bound by ___________________________which provides strength and support
Connective tissue

5. Each muscle fiber contained in a declicate connective tissue sheath called ___________________________
_________________________-connective tissue wrapping a bundle of fibers called a _________________
perimysium
endomysium
fascicle

6. ___________________________= many fascicle bound together w/ this tough coat
Epimysia blend into the strong_,cordlike_________ or aponeurose(sheetlike) that connect muscle to bones,cartilages or connective tissue
Other functions of tendons-besides movement-are durability and conservation of space
epimysium
tendons

8. Smooth Muscle Stomach,bladder,and respiratory passages
No striations and is involuntary
Mainly in walls of hallow visceral organs such as ____________________________________________________________________________________
Propel substances on a definite tract or pathway
Spindle shaped and uninucleate
Stomach,bladder,and respiratory passages

9. Scant endomysium
Most often in 2 layers-one running circularily and one running longitudinally-alternately contract or relaxing changing size and shape of organ

11. Cardiac Muscle Only in heart Forms most of heart walls
________________________but involuntary
Cushioned in bundles w/ small amount of endomysium
striated

12. When heart contracts,internal chambers get smaller,forcing blood into arteries leaving heart
Branching cells joined by junctions-___________________________________These traits and spiral arrangement of bundles allow heart activity to be closely coordinated,giving steady contraction rate
______________________can shift heart into “high gear”
Nervous system
Intercalated discs

13. ****** We focus mostly on skeletal muscle here!

16. Muscle Functions movement posture joints Generating heat
_______________________as a result of muscle contraction;quick response to environment
Maintaining _____________-maintain erect posture despite gravity
Stabilizing ________________-esp. w/ poorly fitting articulating surfaces as in shoulder
_________________________________-by –product of muscle activity;ATP used for contractions and ~40% released as heat to mostly maintain normal body temp for at least 40% of body mass
movement
posture
joints
Generating heat