Smooth Muscle Tissue 7 8 Found in the

Smooth Muscle Tissue (7 -8) • Found in the walls of most organs, in the form of sheets, bundles, or sheaths • Lacks myofibrils, sarcomeres, or striations • Smooth muscle cells – Also smaller than skeletal fibers – Spindle-shaped and have a single nucleus © 2013 Pearson Education, Inc.

Smooth Muscle Tissue (7 -8) • Thick filaments are scattered throughout sarcoplasm – Thin filaments are anchored to the sarcolemma – Causing contraction to be like a twisting corkscrew • Cells are bound together – Resulting in forces being transmitted throughout the tissue © 2013 Pearson Education, Inc.

Smooth Muscle Tissue (7 -8) • Different from other muscle types – Calcium ions from the extracellular fluid are needed to trigger a contraction mechanism that is different from other muscle tissues – Function involuntarily • Can respond to hormones or pacesetter cells © 2013 Pearson Education, Inc.

Figure 7 -10 Cardiac and Smooth Muscle Tissues. Cardiac muscle cell Intercalated discs Cardiac muscle tissue LM x 575 A light micrograph of cardiac muscle tissue. Circular muscle layer T Longitudinal muscle layer L Smooth muscle tissue © 2013 Pearson Education, Inc. LM x 100 Many visceral organs contain several layers of smooth muscle tissue oriented in different directions. Here, a single sectional view shows smooth muscle cells in both longitudinal (L) and transverse (T) sections.

Table 7 -2 A Comparison of Skeletal, Cardiac, and Smooth Muscle Tissues © 2013 Pearson Education, Inc.

Checkpoint (7 -8) 19. How do intercalated discs enhance the functioning of cardiac muscle tissue? 20. Extracellular calcium ions are important for the contraction of what type(s) of muscle tissue? 21. Why can smooth muscle contract over a wider range of resting lengths than skeletal muscle? © 2013 Pearson Education, Inc.

Skeletal Muscle System Names (7 -9) • Based on: – Action • What they do – Origin • The end that stays stationary – Insertion • The end that moves © 2013 Pearson Education, Inc.

Actions (7 -9) • Described as relative to the bone that is moved – Example, "flexion of the forearm" • Described as the joint that is involved – Example, "flexion at the elbow" © 2013 Pearson Education, Inc.

Primary Actions of Muscles (7 -9) • Prime mover, or agonist – The muscle that is chiefly responsible for producing a movement • Antagonist – A muscle that opposes another muscle • Synergist – A muscle that helps the prime mover • Example, flexion of the elbow – The biceps brachii is the prime mover, the triceps brachii is the antagonist, and the brachialis is the synergist © 2013 Pearson Education, Inc.

Table 7 -3 Muscle Terminology (1 of 2) © 2013 Pearson Education, Inc.

Table 7 -3 Muscle Terminology (2 of 2) © 2013 Pearson Education, Inc.

Muscle Terminology (7 -9) • Combining the various terms in Table 7 -3, anatomists name the muscles using: – Location, direction of fibers, number of origins, and/or function • Muscles are organized into two groups 1. Axial muscles (mostly stabilizers) 2. Appendicular muscles (stabilizers or movers of the limbs) © 2013 Pearson Education, Inc.

Figure 7 -11 a An Overview of the Major Skeletal Muscles. Trapezius Clavicle Deltoid Frontalis Temporalis Masseter Sternocleidomastoid Pectoralis major Sternum Latissimus dorsi Serratus anterior External oblique Rectus abdominis Extensor carpi radialis Brachioradialis Flexor carpi ulnaris Biceps brachii Triceps brachii Brachialis Pronator teres Palmaris longus Flexor carpi radialis Flexor digitorum Tensor fasciae latae Vastus lateralis Rectus femoris Patella Tibialis anterior Extensor digitorum © 2013 Pearson Education, Inc. Gluteus medius Iliopsoas Adductor longus Gracilis Sartorius Vastus medialis Fibularis Gastrocnemius Soleus Anterior view

Figure 7 -11 b An Overview of the Major Skeletal Muscles. Sternocleidomastoid Trapezius Deltoid Infraspinatus Teres minor Teres major Latissimus dorsi Brachioradialis Extensor carpi radialis Tensor fasciae latae Semitendinosus Biceps femoris Gastrocnemius Occipitalis Triceps brachii Rhomboid major Flexor carpi ulnaris External oblique Extensor digitorum Extensor carpi ulnaris Gluteus medius Gluteus maximus Adductor magnus Semimembranosus Gracilis Sartorius Soleus Calcaneal tendon © 2013 Pearson Education, Inc. Calcaneus Posterior view

Checkpoint (7 -9) 22. Identify the kinds of descriptive information used to name skeletal muscles. 23. Which muscle is the antagonist of the biceps brachii? 24. What does the name flexor carpi radialis longus tell you about this muscle? © 2013 Pearson Education, Inc.

Axial Muscles (7 -10) • Muscles of the head and neck • Muscles of the spine • Muscles of the trunk • Muscles of the pelvic floor © 2013 Pearson Education, Inc.

Muscles of the Head and Neck (7 -10) • Orbicularis oris – Constricts the mouth opening • Buccinator – Compresses check to blow forcefully • Masseter – Prime mover for chewing • Temporalis and pterygoid – Synergists for chewing • Digastric – Depresses the mandible • Sternocleidomastoid – Rotates head or flexes neck © 2013 Pearson Education, Inc.

Muscles of the Head and Neck (7 -10) • Epicranium, or scalp, contains a two-part muscle, the occipitofrontalis 1. Anterior frontalis 2. Posterior occipitalis • Connected by epicranial aponeurosis • Platysma – Covers ventral neck extending from the base of the neck to the mandible • Mylohyoid – Supports the tongue • Stylohyoid – Connects hyoid to styloid process © 2013 Pearson Education, Inc.

Figure 7 -12 Muscles of the Head and Neck. Epicranial aponeurosis (tendinous sheet) Frontalis Temporalis Orbicularis oculi Occipitalis Buccinator Masseter Sternocleidomastoid Zygomaticus Orbicularis oris Depressor anguli oris Epicranial aponeurosis (tendinous sheet) Frontalis Temporalis Orbicularis oculi Platysma Lateral view Zygomaticus Orbicularis oris Platysma Sternocleidomastoid Lateral pterygoid Medial pterygoid Mandible Lateral view, pterygoid muscles © 2013 Pearson Education, Inc. exposed Masseter Buccinator Depressor anguli oris Trapezius Platysma (cut and reflected) Anterior view

Figure 7 -13 Muscles of the Anterior Neck. Mandible Mylohyoid Stylohyoid Hyoid bone Digastric Sternocleidomastoid (cut) Cartilages of larynx Sternothyroid Sternohyoid Clavicle Cut heads of sternocleidomastoid © 2013 Pearson Education, Inc. Sternocleidomastoid Sternum

Table 7 -4 Muscles of the Head and Neck (1 of 2) © 2013 Pearson Education, Inc.

Table 7 -4 Muscles of the Head and Neck (2 of 2) © 2013 Pearson Education, Inc.

Muscles of the Spine (7 -10) • Splenius capitis and semispinalis capitis – Work together to either extend the head or tilt the head • Erector spinae – Are spinal extensors and include spinalis, longissimus, and iliocostalis • Quadratus lumborum – Flex the spinal column and depress the ribs © 2013 Pearson Education, Inc.

Figure 7 -14 Muscles of the Spine. Semispinalis capitis Splenius capitis Iliocostalis Erector Longissimus spinae muscles Spinalis Quadratus lumborum © 2013 Pearson Education, Inc.

Table 7 -5 Muscles of the Spine © 2013 Pearson Education, Inc.

Axial Muscles of the Trunk (7 -10) • External and internal intercostals – Elevate and depress ribs, respectively • Diaphragm – Muscle used for inhalation of breath • External and internal obliques, and the transversus abdominis – Compress abdomen, can flex spine • Rectus abdominis – Depresses ribs, flexes spine © 2013 Pearson Education, Inc.

Figure 7 -15 Oblique and Rectus Muscles and the Diaphragm. Rectus Xiphoid abdominis process External oblique Inferior vena cava External intercostal Internal intercostal T 10 Central tendon of diaphragm Esophagus Serratus anterior Diaphragm Aorta Spinal cord Erector spinae group Superior view at the level of the diaphragm Serratus anterior Internal intercostal External oblique (cut) External oblique Aponeurosis Linea alba (midline band of dense connective tissue) Internal oblique Rectus abdominis Linea alba External oblique Transversus abdominis Internal oblique L 3 Quadratus lumborum Rectus abdominis Anterior view © 2013 Pearson Education, Inc. Horizontal section view at the level of the umbilicus

Table 7 -6 Axial Muscles of the Trunk © 2013 Pearson Education, Inc.

Muscles of the Pelvic Floor (7 -10) • Form the perineum and support the organs of the pelvic cavity • Flex the coccyx • Control materials moving through the anus and urethra with sphincters © 2013 Pearson Education, Inc.

Figure 7 -16 Muscles of the Pelvic Floor. Deep Dissections Superficial Dissections Urethra External urethral sphincter Ischiocavernosus Bulbospongiosus Vagina Transverse perineus Central tendon of perineum Levator ani Anus External anal sphincter Gluteus maximus Female No differences between deep musculature in male and female Testis Urethra (connecting segment removed) Ischiocavernosus Bulbospongiosus Transverse perineus Anus External urethral sphincter Central tendon of perineum Levator ani Gluteus maximus External anal sphincter © 2013 Pearson Education, Inc. Male

Table 7 -7 Muscles of the Pelvic Floor © 2013 Pearson Education, Inc.

Checkpoint (7 -10) 25. If you were contracting and relaxing your masseter muscle, what would you probably be doing? 26. Which facial muscle would you expect to be well developed in a trumpet player? 27. Damage to the external intercostal muscles would interfere with what important process? 28. If someone were to hit you in your rectus abdominis, how would your body position change? © 2013 Pearson Education, Inc.

Appendicular Muscles (7 -11) • Muscles that position the pectoral girdle • Muscles that move the arm, forearm, and wrist • Muscles that move the hand fingers • Muscles of the pelvic girdle • Muscles that move thigh and leg • Muscles that move the foot and toes © 2013 Pearson Education, Inc.

Muscles That Position Pectoral Girdle (7 -11) • Trapezius – Diamond-shaped muscle, has many actions depending on the region • Rhomboid – Adducts and rotates scapula laterally • Levator scapulae – Adducts and elevates scapula • Serratus anterior – Abducts and rotates scapula • Pectoralis minor and subclavius – Depress and abduct shoulder © 2013 Pearson Education, Inc.

Figure 7 -17 Muscles That Position the Pectoral Girdle. Superficial Dissection Deep Dissection Muscles That Position the Pectoral Girdle Trapezius Muscles That Position the Pectoral Girdle Levator scapulae Rhomboid muscles Scapula Serratus anterior Triceps brachii Posterior view Muscles That Position the Pectoral Girdle Trapezius Levator scapulae Subclavius Pectoralis minor Muscles That Position the Pectoral Girdle Pectoralis minor (cut) Serratus anterior Pectoralis major (cut and reflected) Internal intercostals Biceps brachii External intercostals Anterior view © 2013 Pearson Education, Inc. T 12 vertebra

Table 7 -8 Muscles That Position the Pectoral Girdle © 2013 Pearson Education, Inc.

Muscles That Move the Arm (7 -11) • Deltoid – Abducts arm, supraspinatus assists • Subscapularis, teres major, infraspinatus, and teres minor – Form the rotator cuff • Pectoralis major – Flexes the arm at the shoulder • Latissimus dorsi A&P FLIX™the Rotator An overview (a) – Extends armcuff atmuscles: the shoulder PLAY A&P FLIX™ Rotator cuff muscles: An overview (b) © 2013 Pearson Education, Inc.

Figure 7 -18 Muscles That Move the Arm. Deep Dissection Superficial Dissection Sternum Clavicle Ribs (cut) Muscles That Move the Arm Deltoid Pectoralis major Muscles That Move the Arm Subscapularis Coracobrachialis Teres major Biceps brachii Vertebra T 12 Anterior view Deep Dissection Superficial Dissection Muscles That Move the Arm Supraspinatus Deltoid Latissimus dorsi Vertebra T 1 Muscles That Move the Arm Supraspinatus Infraspinatus Teres minor Teres major Triceps brachii Posterior view © 2013 Pearson Education, Inc.

Table 7 -9 Muscles That Move the Arm © 2013 Pearson Education, Inc.

Muscles That Move the Forearm and Wrist (7 -11) • Biceps brachii – Flexes the elbow and supinates forearm • Triceps brachii – Extends elbow • Brachialis and brachioradialis – Flex elbow • Flexor carpi ulnaris, flexor carpi radialis, and palmaris longus – Flex wrist • Extensor carpi radialis and extensor carpi ulnaris – Extend wrist • Pronators and supinators – Rotate radius © 2013 Pearson Education, Inc.

Muscles That Move the Hand (7 -11) • Extensor digitorum – Extends fingers • Flexor digitorum – Flexes fingers • Abductor pollicis – Abducts thumb • Extensor pollicis – Extends thumb PLAY A&P FLIX™ The elbow joint and forearm: An overview © 2013 Pearson Education, Inc.

Figure 7 -19 Muscles That Move the Forearm and Wrist. Humerus Coracobrachialis Triceps brachii Brachioradialis Extensor carpi radialis Flexor carpi ulnaris Ulna Brachialis Flexor carpi Extensor radialis carpi ulnaris Flexor Extensor digitorum superficialis Abductor pollicis Flexor Extensor retinaculum pollicis Extensor retinaculum Posterior view of right upper limb © 2013 Pearson Education, Inc. Pronator teres Brachioradialis Palmaris longus Flexor carpi ulnaris Pronator quadratus Anterior view of right upper limb Supinator Pronator teres Ulna Radius Anterior view of the muscles of pronation and supination when the limb is supinated

Table 7 -10 Muscles That Move the Forearm, Wrist, and Hand (1 of 2) © 2013 Pearson Education, Inc.

Table 7 -10 Muscles That Move the Forearm, Wrist, and Hand (2 of 2) © 2013 Pearson Education, Inc.

Checkpoint (7 -11) 29. Which muscle do you use to shrug your shoulders? 30. Sometimes baseball pitchers suffer rotator cuff injuries. Which muscles are involved in this type of injury? 31. Injury to the flexor carpi ulnaris would impair which two movements? © 2013 Pearson Education, Inc.

Muscles That Move the Thigh (7 -11) • Gluteal group – Includes gluteus maximus, the largest and most posterior; is a hip extensor • Adductors – Include the adductor magnus, adductor brevis, adductor longus, the pectineus, and the gracilis • Largest hip flexor is the iliopsoas A&P FLIX™ Anterior muscles that cross the hip joint – Made up of the psoas major and the iliacus PLAY © 2013 Pearson Education, Inc.

Figure 7 -20 Muscles That Move the Thigh. Iliac crest Gluteus medius (cut) Gluteus maximus (cut) Sacrum Gluteal region, posterior view Gluteal Group Gluteus medius Gluteus maximus Gluteus minimus Tensor fasciae latae Iliotibial tract Vastus lateralis Sartorius Rectus femoris Biceps femoris Semimembranosus Plantaris Head of fibula L 5 Patellar Lateral ligament view Iliopsoas Group Psoas major Iliacus Adductor Group Pectineus Adductor brevis Adductor longus Adductor magnus Gracilis © 2013 Pearson Education, Inc. Anterior view of the iliopsoas muscle and the adductor group

Table 7 -11 Muscles That Move the Thigh (1 of 3) © 2013 Pearson Education, Inc.

Table 7 -11 Muscles That Move the Thigh (2 of 3) © 2013 Pearson Education, Inc.

Table 7 -11 Muscles That Move the Thigh (3 of 3) © 2013 Pearson Education, Inc.

Muscles That Move the Leg (7 -11) • Knee flexors are the hamstrings – Biceps femoris, semimembranosus, semitendinosus, and the sartorius • Knee extensors are the quadriceps femoris – Which include the rectus femoris and the three vastus muscles • Popliteus muscle – Unlocks the knee joint © 2013 Pearson Education, Inc.

Figure 7 -21 Muscles That Move the Leg. Iliac crest Gluteus medius Tensor fasciae latae Gluteus maximus Iliacus Psoas major Iliopsoas Tensor fasciae latae Pectineus Adductor longus Gracilis Adductor magnus Gracilis Iliotibial tract Flexors of the Knee Sartorius Extensors of the Knee (Quadriceps muscles) Rectus femoris Biceps femoris Vastus lateralis Semitendinosus Vastus medialis Vastus intermedius (deep to above muscles) Semimembranosus Quadriceps tendon Sartorius Patella Popliteus Patellar ligament Hip and thigh, posterior view © 2013 Pearson Education, Inc. Quadriceps and thigh muscles, anterior view

Table 7 -12 Muscles That Move the Leg © 2013 Pearson Education, Inc.

Muscles That Move the Foot and Toes (7 -11) • The gastrocnemius of the calf is assisted by the underlying soleus – They share a common calcaneal tendon, and are both plantar flexors • Fibularis muscles – Produce eversion and plantar flexion • Tibialis – Cause inversion of the foot – Tibialis anterior is largest and produces dorsiflexion © 2013 Pearson Education, Inc.

Figure 7 -22 a Muscles That Move the Foot and Toes. Superficial Dissection Deep Dissection Ankle Extensors Plantaris Head of fibula Gastrocnemius Soleus Popliteus Ankle Extensors (Deep) Tibialis posterior Fibularis longus Fibularis brevis Digital Flexors Gastrocnemius (cut and removed) Flexor digitorum longus Flexor hallucis longus Calcaneal tendon Tendon of flexor hallucis longus Calcaneus Tendons of fibularis muscles Posterior views © 2013 Pearson Education, Inc. Tendon of flexor digitorum longus

Figure 7 -22 b Muscles That Move the Foot and Toes. Iliotibial tract Head of fibula Ankle Extensors Gastrocnemius Ankle Flexors Fibularis longus Tibialis anterior Soleus Fibularis brevis Digital Extensors Extensor digitorum longus Tendon of extensor hallucis longus Calcaneal tendon Retinacula © 2013 Pearson Education, Inc. Lateral view

Figure 7 -22 c Muscles That Move the Foot and Toes. Patella Medial surface of tibial shaft Patellar ligament Ankle Flexors Ankle Extensors Tibialis anterior Gastrocnemius Soleus Digital Extensors Tibialis posterior Tendon of extensor hallucis longus Calcaneal tendon Retinacula Tendon of tibialis anterior © 2013 Pearson Education, Inc. Medial view

Table 7 -13 Muscles That Move the Foot and Toes (1 of 2) © 2013 Pearson Education, Inc.

Table 7 -13 Muscles That Move the Foot and Toes (2 of 2) © 2013 Pearson Education, Inc.

Checkpoint (7 -11) 32. You often hear of athletes suffering a "pulled hamstring. " To what does this phrase refer? 33. How would you expect a torn calcaneal tendon to affect movement of the foot? © 2013 Pearson Education, Inc.

Four Effects of Aging on Skeletal Muscle (7 -12) 1. Muscle fibers become smaller in diameter 2. Muscles become less elastic and more fibrous 3. Tolerance for exercise decreases due to a decrease in thermoregulation 4. Ability to recover from injury is decreased © 2013 Pearson Education, Inc.

Checkpoint (7 -12) 34. Describe general age-related effects on skeletal muscle tissue. © 2013 Pearson Education, Inc.

Exercise Engages Multiple Systems (713) • Cardiovascular system – Increases heart rate and speeds up delivery of oxygen • Respiratory system – Increases rate and depth of respiration • Integumentary system – Dilation of blood vessels and sweating combine to increase cooling • Nervous and endocrine systems – Control of heart rate, respiratory rate, and release of stored energy © 2013 Pearson Education, Inc.

Removes excess body heat; synthesizes vitamin D 3 for calcium and phosphate absorption; protects underlying muscles Provides mineral reserve for maintaining normal calcium and phosphate levels in body fluids; supports skeletal muscles; provides sites of attachment Muscular System Skeletal muscles pulling on skin of face produce facial expressions Provides movement and support; stresses exerted by tendons maintain bone mass; stabilizes bones and joints Body System (Page 138) Muscular System Integumentary 7 -23 SYSTEM Figure INTEGRATOR Skeletal (Page 188) Skeletal Integumentary Body System © 2013 Pearson Education, Inc. Endocrine (Page 376) Reproductive (Page 671) Urinary (Page 637) Digestive (Page 572) Respiratory (Page 532) Lymphatic (Page 500) Cardiovascular (Page 467) The muscular system performs five primary functions for the human body. It produces skeletal movement, helps maintain posture and body position, supports soft tissues, guards entrances and exits to the body, and helps maintain body temperature. Nervous (Page 302) The MUSCULAR System

Checkpoint (7 -13) 35. What major function does the muscular system perform for the body as a whole? 36. Identify the physiological effects of exercise on the cardiovascular, respiratory, and integumentary systems, and indicate the relationship between these physiological effects and the nervous and endocrine systems. © 2013 Pearson Education, Inc.