5 lesson 5.1: muscle tissue categories and functions lesson 5.2: skeletal muscle actions lesson 5.3:...

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Lesson 5.1: Muscle Tissue Categories and Functions

Lesson 5.2: Skeletal Muscle Actions

Lesson 5.3: The Major Skeletal Muscles

Lesson 5.4: Common Injuries and Disorders of Muscles

The Muscular System

Lesson 5.1

Muscle Tissue Categories and

Functions

Chapter 5: The Muscular System

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc.

• categories– skeletal– smooth – cardiac

• functions– behavioral properties– tension and types of skeletal muscle contractions

Muscle Tissue


• skeletal– voluntary– striated

• smooth– involuntary– no striations

• cardiac– involuntary– striated– intercalated disks

Muscle Tissue Categories


Muscle Tissue Categories


• sarcolemma and endomysium surrounds the muscle fiber

• perimysium bundles groups of muscle fibers to make up a fascicle

• epimysium encloses several fascicles to make up a muscle

• aponeurosis connects muscle to other tissues

Skeletal Muscle Organization


Skeletal Muscle Organization


True or False?

1. Smooth muscle is voluntary.

2. Cardiac muscle has branching fibers.

3. Smooth muscle is multinucleate.

4. Perimysium wraps fascicles to make a muscle.

5. Endomysium surrounds the muscle fibers.

Review and Assessment


• extensibility–stretch• elasticity–snap back• irritability–respond• contractility–shorten

Behavioral Properties of Muscle


• tension and types of skeletal muscle contraction– agonist–moves bone– antagonist–opposes the movement of the agonist

Muscle Tissue Functions


• agonist contracts, antagonist relaxes

Concentric Contraction


• agonist contracts while lengthening, antagonist relaxes

Eccentric Contraction


• both agonist and antagonist contract

Isometric Contraction


Match these words with 1–5 below: extensibility, elasticity, irritability, contractility, agonist, antagonist.

1. respond

2. opposes movement

3. stretch

4. shorten

5. causes movement


Lesson 5.2

Skeletal Muscle Actions



• the motor unit• skeletal fiber types• muscular strength, power, and endurance

Skeletal Muscle


• group of muscle fibers under the control of one motor neuron

The Motor Unit


• acetylcholine crosses the synaptic cleft at the neuromuscular junction

• depolarization takes place on muscle fiber• action potential begins

Generating Action Potentials


• sarcomeres shorten by actin filaments sliding along myosin filaments

Contraction of the Sarcomeres


• action potential always causes entire motor unit muscle fibers to contract

• all-or-none law

Maximum Tension and Return to Relaxation


True or False?

1. An action potential causes one half of the fibers in the motor unit to contract.

2. Acetylcholine crosses the synaptic cleft at the neuromuscular junction.

3. The sarcomeres lengthen by myosin filaments sliding over actin filaments.



• slow-twitch• fast-twitch

– type IIa– type IIb

Skeletal Muscle Fiber Types


• parallel fiber arrangements– fusiform– bundled– triangular

• pennate fiber arrangements– unipennate– bipennate– multipennate

Skeletal Muscle Fiber Architecture


• rotary force that muscles can produce at a joint– the maximum weight you can lift is a measurement of

muscular strength

Muscular Strength


• force x velocity– how fast you can sprint is a measurement of muscle

power

Muscle Power


• muscle tension/time– how far you can run is a measurement of muscle

endurance

Muscle Endurance


Match these words with 1–5 below: muscle endurance, muscular strength, muscle power, Type I, Type IIb.

1. force x velocity

2. muscle tension/time

3. rotary force that muscles can produce at a joint

4. slow twitch, slow fatigue

5. fast twitch, fast fatigue


Lesson 5.3

The Major Skeletal Muscles



• directional motions• head and neck muscles• trunk muscles• upper limb muscles• lower limb muscles

The Major Skeletal Muscles


• origin – fixed end of a muscle

• insertion– movable end of a muscle

Skeletal Muscle Attachments


• flexion• extension• hyperextension• dorsiflexion• plantar flexion

Sagittal Plane Movements


• abduction• adduction• inversion• eversion• radial deviation• ulnar deviation

Frontal Plane Movements


• medial rotation• lateral rotation• pronation• supination

Transverse Plane Movements


• circumduction• opposition

Multiplanar Movements


True or False?

1. Circumduction is a multiple plane movement.

2. Supination is a multiple plane movement.

3. The insertion is the fixed end of a muscle.

4. Extension is a sagittal plane movement.

5. Adduction is a frontal plane movement.



Head and Neck Muscles


Trunk Muscles


Upper Limb Muscles


Lower Limb Muscles


Match these words with 1–4 below: head, trunk, upper limb, lower limb.

1. temporalis

2. brachioradialis

3. external oblique

4. biceps femoris


Lesson 5.4

Common Injuries and Disorders of

Muscles



• strain–overstretched muscle– grade I, II, III

• contusion–bruised muscle– myositis ossificans

• cramps–spasming muscle• delayed onset muscle soreness–tear

Muscle Injuries


• tendinitis–inflamed tendon

• tendinosis–degeneration of a tendon

Tendon Injuries

Val Thoermer/Shutterstock.com


• rotational injury at shoulder• overuse of elbow• shin splints• whiplash

Joint Injuries


• muscular dystrophy• hernia

Muscle Disorders


True or False?

1. Tendinitis is muscle strain.

2. A contusion is a bruise.

3. Whiplash is a joint injury.

4. A hernia is a tendon injury.

5. A strain is an over stretch of a tendon.


5 lesson 5.1: muscle tissue categories and functions lesson 5.2: skeletal muscle actions lesson 5.3:...

Documents

educational use

smooth muscle

cardiac muscle

muscle aponeurosis

assessment slide

relaxation slide

skeletal muscle actions

group of muscle fibers