the muscular system chapter 11. please note: the muscular system includes all the skeletal muscles...
TRANSCRIPT
![Page 1: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/1.jpg)
The Muscular System
Chapter 11
![Page 2: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/2.jpg)
Please Note:
• The muscular system includes all the skeletal muscles that can be controlled voluntarily.
• There are about 700 identified skeletal muscles in the human body.
![Page 3: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/3.jpg)
I. Organization of Skeletal Muscle Fibers
A. Factors that determine the effects of a muscle contraction:
1. The anatomical arrangement of the muscle fibers
2. The way the muscle attaches to the bones of the skeletal system
![Page 4: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/4.jpg)
B. Fascicles- bundles of muscle fibers within a skeletal muscle.
![Page 5: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/5.jpg)
C. 4 Patterns of Fascicle Organization
1. Parallel Muscles- fascicles are parallel to the long axis of the muscle.
a. Most common type.
b. Some are flat bands.
c. Some are spindle-shaped w/ a central body (aka belly or gaster)
d. Ex. biceps brachii
![Page 6: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/6.jpg)
![Page 7: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/7.jpg)
2. Convergent Muscles- fascicles are based over a broad area, but unite at a common attachment site.
a. Fan- or triangle-shaped
b. Ex. pectoralis group (chest muscles)
![Page 8: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/8.jpg)
![Page 9: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/9.jpg)
3. Pennate Muscles- fascicles form a common angle with the tendon.
a. Unipennate- Fibers go off in one direction Ex. extensor digitorum
b. Bipennate- Fibers go off in two directions Ex. rectus femoris
c. Multipennate- Fibers go off in many directions
Ex. deltoid
![Page 10: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/10.jpg)
![Page 11: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/11.jpg)
4. Circular Muscles (aka sphincter)- fibers are concentrically arranged around an opening or recess.
a. Contracting decreases the diameter of the opening.
b. Guard entrances and exits of internal passageways.
c. Ex. orbicularis oris (mouth)
![Page 12: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/12.jpg)
![Page 13: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/13.jpg)
(a review from physical science…)
Levers are:– simple machines
– structures that move on a fixed point called a fulcrum.
– When effort force is applied, a lever moves about the fulcrum, overcoming the resistance.
![Page 14: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/14.jpg)
II. 3 Classes of Levers in the Body
A. First Class Levers
1. The fulcrum lies between the applied force (AF) and the resistance (R)
2. Ex.a. Teeter-totter
b. scissors
![Page 15: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/15.jpg)
B. Second Class Levers
1. The resistance is located between the applied force and the fulcrum.
2. Ex.a. Wheelbarrowb. Hinged doors
![Page 16: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/16.jpg)
C. Third Class Levers1. The applied force is between the resistance and
the fulcrum.
2. This is the most common type of lever in the body.
3. Ex.a. Sweeping
b. Shoveling
![Page 17: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/17.jpg)
III. Muscle Terminology
A. Muscle Attachment1. Origin- where a muscle begins
a. Generally remains stationaryb. Generally proximal
2. Insertion- where a muscle endsa. Generally moveableb. Generally distal
3. Contraction results in the shortening of the distance between the origin & insertion, which causes movement at the insertion end.
![Page 18: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/18.jpg)
![Page 19: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/19.jpg)
Actions (review)
• Flexion• Rotation• Adduction• Pronation• Protraction• Inversion• Lateral Flexion• Depression
• Extension• Circumduction• Abduction• Supination• Retraction• Eversion• Opposition • Elevation
![Page 20: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/20.jpg)
IV. Grouping Muscles According to their Primary Actions:
A. Prime Mover / Agonist- muscle whose contraction is chiefly responsible for producing a particular movement.
– Ex. biceps brachii
B. Antagonists- muscle that opposes agonist.– Ex. triceps brachii
![Page 21: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/21.jpg)
C. Synergist- assists the prime mover
D. Fixator- stabilizes agonist to prevent movement.
![Page 22: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/22.jpg)
V. Naming Skeletal Muscle
A. Fascicle Organization:1. Rectus- “straight”- parallel muscles whose
fibers run along the long axis of the body
2. Transversus- muscles whose fibers run across the long axis of the body
3. Obliquus- muscles whose fibers run at an angle to the long axis of the body
![Page 23: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/23.jpg)
B. Relative Position:1. Externus- visible at body surface
2. Superficialis- visible at body surface
3. Internus- found beneath the surface
4. Profundus- found beneath the surface
5. Extrinsic- superficial muscles that stabilize an organ
6. Intrinsic- muscles located entirely within the organ
![Page 24: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/24.jpg)
C. Structure:1. Ex. biceps brachii (2 tendons of origin) 2. Ex. quadriceps group (4 tendons of origin)
D. Size:1. Longus / Brevis - long / short muscles2. Major / Minor - large / small muscles
E. Shape:1. Ex. Trapezius- trapezoid-shaped2. Ex. Rhomboideus- rhomboid-shaped
![Page 25: The Muscular System Chapter 11. Please Note: The muscular system includes all the skeletal muscles that can be controlled voluntarily. There are about](https://reader030.vdocuments.site/reader030/viewer/2022032805/56649ef45503460f94c06e41/html5/thumbnails/25.jpg)
F. Origin & Insertion:1. Ex. genioglossus
a. Origin: chin “geneion”
b. Insertion: tongue “glossus”
G. Action:1. Flexor
2. Extensor
3. …