Transcript Chapter 11 - Horizon Medical Institute

CHAPTER
11
Anatomy and
Physiology of the
Human Body
UNIT
6
The Muscular System
11 - 2
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Major Skeletal Muscles
11 - 3
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Skeletal Muscle Tissue



Attaches to bone to permit movement
Skeletal muscle movement is voluntary.
Skeletal muscle cells are long and strong
and are arranged in bundles enclosed in
tough connective tissue sheaths.
11 - 4
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Smooth Muscle Tissue


Small, delicate muscle cells found
throughout the internal organs of the
body
Smooth muscle activity is involuntary and
occurs constantly in functions such as
breathing, peristalsis, blood vessel
contraction, and pupil dilation.
11 - 5
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Cardiac Muscle Tissue



Muscle tissue found only in the heart
Arranged in a continuous network
without sheath separation
When one cell receives the signal to
contract, all neighboring cells are
stimulated and they contract together.
11 - 6
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Six Functions of Skeletal Muscles
1.
2.
3.
4.
5.
6.
Contractions provide heat.
Contractions permit movement.
Hold the trunk and head erect
Protect blood vessels and nerves
Help blood flow return to the heart
Provide protective padding for internal
organs
11 - 7
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Muscle Activity and Heat Production


Muscles use stored glycogen as an
energy source.
As this fuel is used, heat is produced and
warms the body.
11 - 8
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Muscle Teams



11 - 9
When muscles contract they become
shorter and thicker.
Skeletal muscles that bend joints are
called flexors.
Skeletal muscles that straighten out a
joint are called extensors.
(continued)
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Muscle Teams


When a flexor muscle is partnered with
an extensor muscle they work as a team
to bend and straighten joints.
The biceps and triceps of the upper arm
are an example of a muscle team.
11 - 10
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Muscle Tone


Most skeletal muscles are partially
contracted at all times so that the body
remains erect.
This constant state of contraction is
known as muscle tone.
11 - 11
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Muscle Sheaths and Bursae

Muscle sheaths


Membranes that separate muscle groups to
prevent friction from movement
Bursae

A sheath that is shaped like a sac and has a
slippery fluid lining that acts as a cushion to
minimize pressure and friction
11 - 12
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Peristalsis

Involuntary contraction of smooth muscle
that results from alternate contraction
and relaxation of the layers of the
smooth muscle
11 - 13
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Sphincter Muscles

Smooth, donut-shaped muscles that
pinch shut intermittently to control the
flow of blood, food, or liquid
11 - 14
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Tendons and Ligaments

Tendons



Strong, fibrous connective tissue sheaths
that do not bend or stretch
Tendons attach muscle to bone.
Ligaments


Flexible, fibrous tissue that supports organs
Tendons connect bones to bones at the
joints.
11 - 15
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Diseases and Disorders
11 - 16
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Bursitis and Tendonitis

Bursitis


Painful inflammation of the bursae that cover
and lubricate muscles and tendons
Tendonitis

Painful inflammation of the tendons and
muscle attachments to the bone
11 - 17
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Fibromyalgia Syndrome

Chronic musculoskeletal condition that
causes widespread pain and the
presence of tender points or trigger
points throughout the body
11 - 18
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Muscular Dystrophy

Group of congenital disorders that result
in progressive wasting away of skeletal
muscle and eventually death

Duchenne’s


Diagnosed usually by age 1; death occurs by age
10 to 15
Erb’s

Slow progression of atrophy that occurs later in
childhood or adolescence
11 - 19
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Mixed Dystrophy



Does not appear to be inherited
Can affect both sexes
Usually begins between ages 30 and 50;
death usually occurs within 5 years after
onset
11 - 20
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Torticollis


Congenital or acquired neck deformity
that bends the head toward the affected
side
Caused by shortening or spasms of the
sternocleidomastoid muscle
11 - 21
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Unit Summary



What are the characteristics of, and
differences between, skeletal, smooth,
and cardiac muscle?
What does the term flexor refers to?
How does food move through the body?
11 - 22
Copyright © 2008 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.