Chapter 7 Muscular SystemChapter 7 Muscular System

Learning OutcomesLearning Outcomes

1.Describe the muscular system.2.Describe the three basic types of

muscle tissue.3.Explain the primary functions of

muscles.4.Analyze, build, spell, and pronounce

medical words.

Learning OutcomesLearning Outcomes

5. Describe diagnostic and laboratory tests related to the muscular system.

Anatomy and Physiology OverviewAnatomy and Physiology Overview

• The muscular system is composed of all the muscles in the body and works in coordination with the skeletal and nervous systems.

• Muscles– Provide the mechanism for movement of

the body.– Produce heat.– Help maintain posture and stability.

Anatomy and Physiology OverviewAnatomy and Physiology Overview

• Muscles make up approximately 42% of body weight.

• Muscles are composed of long, slender cells known as fibers.

• Each muscle consists of a group of fibers held together by connective tissue and enclosed in a fibrous sheath or fascia.

Figure 7.2Types of muscle tissue.

Types of MusclesTypes of Muscles

• Cardiac muscle– Muscle of the heart (myocardium) is

involuntary but striated in appearance.– Under control of the autonomic nervous

system.– Has specialized neuromuscular tissue

located within the right atrium.

Types of MusclesTypes of Muscles

• Cardiac muscle– Contraction can occur even without an

initial nervous input because of pacemaker cells.

– Cardiac muscle cells rely on an ample blood supply to deliver oxygen and nutrients and to remove waste products, such as carbon dioxide.

Types of MusclesTypes of Muscles

• Smooth muscle– Also called involuntary, visceral, or

unstriated.– Not controlled by the conscious part of the

brain.– Under the control of the autonomic nervous

system.– Includes muscles of internal organs of the

digestive, respiratory, and urinary tract plus certain muscles of the eye and skin.

TABLE 7.1 Muscular System at-a-Glance

Types of MusclesTypes of Muscles

• Skeletal Muscle– Also known as voluntary or striated muscle.– Controlled by the conscious part of the

brain and attaches to the bones.– Has a cross-striped appearance (striated).– Varies in size, shape, arrangement of

fibers, and means of attachment to bones.

Types of MusclesTypes of Muscles

• Muscles have three distinguishable parts:– the body or main portion.– the origin (the more fixed attachment of

the muscle to the stationary bone).– the insertion (the point of attachment of a

muscle to the bone that it moves).

Muscle NamesMuscle Names

• Muscle location• Muscle size• Muscle purpose • Muscle shape

Figure 7.3Selected skeletal muscles and the Achilles tendon (anterior and posterior

view).

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Anatomy and Physiology OverviewAnatomy and Physiology Overview

• Each fiber within a muscle receives its own nerve impulses and has its own stored supply of glycogen as fuel for energy.

• Blood and lymphatic vessels in muscle tissue supply nutrition and oxygen to muscles.

Figure 7.1Skeletal muscle consists of a group of fibers held together by connective

tissue. It is enclosed in a fibrous sheath (fascia).

Ligament – B2B Tendon – M2B

Functions of the Musculoskeletal Functions of the Musculoskeletal System System

• Tendons- Attach muscles to bones

• Ligaments – ligament/o Bands of connective tissue that connect bones, cartilages and other structures

Types of MusclesTypes of Muscles

• Means of attachment for skeletal muscle:– Tendon (a band of connective tissue, varies

in length from less than 1 inch to more than 1 foot)

– Aponeurosis (a wide, thin, sheetlike tendon)

Types of MusclesTypes of Muscles• Muscles and nerves function together as a motor

unit.• Skeletal muscles perform in groups and are

classified as follows:• Prime mover/agonist is the prime muscle

working in a particular exercise or movement. It’s this muscle that creates an action.

• Antagonist is the muscle that’s directly opposing the agonist muscle. As the agonist contracts, the antagonist relaxes.

• Synergist – is working together (aka, stablizers)

Pg 178Agon/o Agony, a contest Path/o Disease

Amputat/o To cut through Prosth/e An addition

Brach/I Arm Rhabd/o Rod

Cleid/o Clavicle Rotat/o To turn

Clon/o Turmoil Sarc/o Flesh

Ducto/o To lead Stern/o Sternum

Dermat/o Skin Synov/o Synovial

Fasci/o A band Ten/o Tendon

Fibr/o Fiber Therm/o Hot, Heat

Is/o Equal Ton/o Tone,Tension

Muscul/o Muscle Tors/o Twisted

My/o Muscle Tort/I Twisted

Nuero/o nerve Volunt/o Will

How many words can we define?How many words can we define?