{"id":666,"date":"2015-08-20T14:32:31","date_gmt":"2015-08-20T14:32:31","guid":{"rendered":"http:\/\/sites.msudenver.edu\/haysc\/?page_id=666"},"modified":"2016-10-12T14:10:29","modified_gmt":"2016-10-12T14:10:29","slug":"outline-2-bio-3220-muscular-system","status":"publish","type":"page","link":"https:\/\/sites.msudenver.edu\/haysc\/biology-courses\/comparative-vertebrate-anatomy-bio-3220\/outline-2-bio-3220-muscular-system\/","title":{"rendered":"Outline-2, BIO 3220, Muscular System"},"content":{"rendered":"

I. MUSCULAR SYSTEM<\/strong><\/p>\n

A. Overall function –\u00a0Locomotion, posture, protection, heat production<\/em><\/p>\n

B. Classification<\/p>\n

1. Skeletal\u00a0<\/strong>(is striated)<\/p>\n

a. Muscle fiber –\u00a0Muscle cell<\/em><\/p>\n

1. Multinucleate<\/p>\n

2. Myofibrils –\u00a0Striated cylinders within myofiber<\/em><\/p>\n

3. Myofilaments –\u00a0Proteins which interlock and result in contraction<\/em><\/p>\n

a. Actin –\u00a0Thin myofilament; has receptor site for myosin<\/em><\/p>\n

b. Myosin –\u00a0Thick myofilament; has receptor site for actin & ATP<\/em><\/p>\n

c. Contraction-\u00a0Myosin heads attach to actin and with the energy from ATP do a Power Stroke, swiveling towards the center of the sarcomere resulting in shortening of sarcomere.<\/em><\/p>\n

4. Sarcomere –\u00a0Distance from Z line to Z line; basic unit of contraction; Actin is attached to Z line & is pulled towards the center of the sarcomere by myosin’s power stroke.<\/em><\/p>\n

b. Motor neurons & motor units –\u00a0Skeletal muscle cannot contract without stimulation from a motor neuron. The motor neuron plus the number of myofibers it innervates comprise a motor unit.<\/em><\/p>\n

c. Somatic muscles {all skeletal M. are in this category except branchiomeric M.(which are skeletal muscle but visceral muscles since they operate the visceral skeleton}<\/p>\n

1. Voluntary<\/p>\n

2. Body wall & appendages<\/p>\n

a. Tail<\/p>\n

b. Hypobranchial<\/p>\n

c. Tongue<\/p>\n

d. Extrinsic eyeball<\/p>\n

3. Myotome derivatives [segmented] (phylogenetically or by ontogeny) or Hypomere\u00a0(Refer back to early development notes.)<\/em><\/a><\/p>\n

4. Orients body in external environment<\/p>\n

d. Color & Endurance<\/p>\n

1. Red fibers<\/p>\n

a. More blood supply – aerobic metabolism<\/p>\n

b. Myoglobin –\u00a0Red pigmented protein that stores oxygen<\/em><\/p>\n

c. Fatigue resistant<\/p>\n

d. Fish-cruising long distances; tetrapods-posture<\/p>\n

2. White fibers<\/p>\n

a. Anaerobic metabolism<\/p>\n

b. Fatiguable<\/p>\n

c. Fish-spurts of swimming; tetrapods-sprints<\/p>\n

2. Cardiac Muscle<\/strong><\/p>\n

a. Intercalated disks –\u00a0Important in linking all cardiac muscle cells together so that the heart contracts in unison.<\/em><\/p>\n

b. Involuntary<\/p>\n

c. Lateral plate mesoderm in origin<\/p>\n

3. Smooth muscle<\/strong><\/p>\n

a. Involuntary<\/p>\n

b. Lateral plate mesoderm origin<\/p>\n

c. Regulates internal environment<\/p>\n

d. Innervated by ANS<\/p>\n

e. Smooth muscle is in wall of tubular & hollow organs = visceral<\/p>\n

f. Intrinsic eye muscles<\/p>\n

g. Erectors of feathers & hairs<\/p>\n

C. Gross features of skeletal muscle<\/p>\n

1. Origin, insertion<\/p>\n

2. Tendon, aponeurosis, fascia<\/p>\n

3. Muscle shapes<\/p>\n

a. Strap [sternocleidomastoid]\n

b. Teardrop [pectorals]\n

c. Spindle [extremities]\n

d. Heads<\/p>\n

e. Sheets [abdominals]\n

f. Fan [trapezius]\n

g. Circular\/sphincter<\/p>\n

h. Pinnate [diaphragm]\n

D. Actions of skeletal muscle<\/p>\n

1. Flex\/extend<\/p>\n

2. Adduct\/abduct<\/p>\n

3. Levator\/depressor<\/p>\n

4. Protract\/retract<\/p>\n

5. Constrict\/dilator<\/p>\n

6. Rotator<\/p>\n

7. Supinator\/pronator<\/p>\n

8. Tensor [taut]\n

9. AGONIST, ANTAGONIST, SYNERGIST\u00a0Primary mover; muscle opposing movement; muscle helping movement<\/em><\/p>\n

E. Development\/Phylogeny<\/p>\n

1. Position<\/p>\n

2. Embryology –\u00a0Helps to provide for major muscle categories.<\/em><\/p>\n

3. Nerve supply –\u00a0Shown to be most consistent indicator of homology.<\/em><\/p>\n

4. Mesoderm\u00a0(Refer back to your early development notes.)<\/a><\/em><\/p>\n

a. Dorsal = epimere = Somite<\/p>\n

1. Myotome –\u00a0Becomes most muscles except branchiomeric.<\/em><\/p>\n

2. Sclerotome & dermatome<\/p>\n

b. Lateral plate = hypomere<\/p>\n

1. Somatic –\u00a0Muscles of body wall<\/em><\/p>\n

2. Splanchnic –\u00a0Smooth muscle of gut & cardiac muscle<\/em><\/p>\n

\n

F. AXIAL MUSCLES<\/strong><\/p>\n

1. Trunk, tail, hypobranchial, tongue, extrinsic eye muscles<\/p>\n

2. General features<\/p>\n

a. Metamerism – myomeres<\/p>\n

1. Develop embryologically from Somites, specifically myotomes<\/p>\n

2. Myosepta<\/p>\n

3. Hypomere contributes in higher vertebrates<\/p>\n

3. AGNATHANS<\/strong><\/p>\n

a. Simple<\/p>\n

b. Segments<\/p>\n

c. Myotomes<\/p>\n

4. JAWED FISH<\/strong><\/p>\n

a. Horizontal \/ Lateral Septum<\/p>\n

b. Epaxial Muscles<\/p>\n

1. Myotomes<\/p>\n

2. Dorsal rami of spinal nerves [tetrapods too]\n

3. Extend spine & some lateral flexion<\/p>\n

4. Extrinsic eye muscles<\/p>\n

a. Head myotomes<\/p>\n

b. Cranial Nerves III, IV, VI<\/p>\n

5. Epibranchial<\/p>\n

c. Hypaxial Muscles<\/p>\n

1. Myotomes<\/p>\n

2. Ventral rami of spinal nerves<\/p>\n

3. Ventroflex, lateral bending<\/p>\n

4. Hypobranchial<\/p>\n

a. Location<\/p>\n

b. Origin<\/p>\n

c. Function –\u00a0Respiratory and feeding<\/em><\/p>\n

5. TETRAPODS\u00a0<\/strong>–\u00a0SEE Vertebrate muscles page<\/a><\/p>\n

a. Epaxial trunk muscles –\u00a0Dorsal, skull to tail<\/em><\/p>\n

1. Dorsalis trunci {amphibians, not Anurans}<\/p>\n

2. Intervertebrals –\u00a0Deep<\/em><\/p>\n

3. Longissimus –\u00a0Lateral & long; dominant spine extensor<\/em><\/p>\n

4. Spinales –\u00a0Medial spine muscle<\/em><\/p>\n

Multifidus spinae –\u00a0Combination of Spinales & Intervertebral in lumbar region in some mammals to stabilize lumbar region.<\/em><\/p>\n

5. Iliocostalis –\u00a0Most lateral epaxial spine muscle. Important in reptile undulating motion.<\/em><\/p>\n

6. Trends<\/p>\n

Decreased in tail & trunk in reptiles, birds, mammals, but increased in neck<\/em><\/p>\n

b. Hypaxial –\u00a0Trend for myomeres to disappear and sheets of muscles form a sling<\/em><\/p>\n

1. Subvertebrals –\u00a0Below transverse processes; Flex spine<\/em><\/p>\n

2. Lateral –\u00a0Support & compress body wall<\/em><\/p>\n

a. Obliques<\/p>\n

b. Transverse<\/p>\n

c. Intercostals –\u00a0Amniotes only<\/em><\/p>\n

3. Rectus abdominis –\u00a0Ventroflex & compress abdomen<\/em><\/p>\n

4. Diaphragm –\u00a0Breathing muscle unique to mammals<\/em><\/p>\n

c. Hypobranchial and Tongue muscles<\/p>\n

1. Function –\u00a0Stabilize hyoid & larynx<\/em><\/p>\n

2. Tongue [Lingu-,Gloss-]\n

d. Extrinsic eye muscles<\/p>\n

1. Voluntary<\/p>\n

2. Obliques –\u00a0Rotates eye along its transverse axis<\/em><\/p>\n

3. Rectus –\u00a0Up, down, side to side<\/em><\/p>\n

4. Retractor in some<\/p>\n

\n

G. APPENDICULAR MUSCLES<\/strong><\/p>\n

1. Definition –\u00a0Innervated by ventral ramus of spinal nerves<\/em><\/p>\n

2. FISH<\/strong><\/p>\n

a. Origin –\u00a0Extensions of hypaxials of body wall<\/em><\/p>\n

1. Paired fins –\u00a0From myotome<\/em><\/p>\n

2. Median dorsal fin –\u00a0Not appendicular muscles\/<\/em>From myotome of epaxials<\/em><\/p>\n

3. Median ventral fin –\u00a0Not appendicular muscles\/<\/em>From myotome of hypaxials<\/em><\/p>\n

b. Dorsal mass of fins – extensors\/abductors<\/p>\n

c. Ventral mass – flexors\/adductors<\/p>\n

3. TETRAPOD<\/strong>–\u00a0SEE Vertebrate Muscle page<\/a><\/p>\n

a. Pectoral limb<\/p>\n

1. Dorsal group<\/p>\n

a. Deltoid –\u00a0Arm abductor<\/em><\/p>\n

b. Latissimus dorsi –\u00a0Very constant among vertebrates; limb retractor<\/em><\/p>\n

c. Teres major –\u00a0Medial rotator of arm; formed from Latissimus dorsi<\/em><\/p>\n

d. Subcoracoscapularis>>> subscapularis –\u00a0Scapula to humerus<\/em><\/p>\n

e. Scapulohumeralis anterior>>> teres minor –\u00a0Rotates humerus<\/em><\/p>\n

f. Triceps –\u00a0Humerus to ulna; Forearm extensor<\/em><\/p>\n

g. Forearm & hand extensors –\u00a0Lateral epicondyle of humerus to wrist\/hand<\/em><\/p>\n

h. Cutaneous trunci = Cutaneous maximus –\u00a0Armpit to trunk; twitches skin<\/em><\/p>\n

2. Ventral group<\/p>\n

a. Pectoralis –\u00a0Humerus adductor; Important wing muscle to lower wing<\/em><\/p>\n

b. Supracoracoideus –\u00a0Important wing muscle to elevate wing<\/em><\/p>\n

1. Supraspinatus –\u00a0Extends humerus<\/em><\/p>\n

2. Infraspinatus –\u00a0Humerus lateral rotation<\/em><\/p>\n

c. Coracobrachialis –\u00a0Arm flexor\/adductor<\/em><\/p>\n

d. Biceps brachii & Brachialis –\u00a0Forearm flexor<\/em><\/p>\n

e. Forearm, wrist & digit flexors –\u00a0Medial epicondyle of humerus to wrist & digits<\/em><\/p>\n

b. Pelvic limb<\/p>\n

1. Dorsal group<\/p>\n

a. Iliofemoralis & Iliofibularis –\u00a0Thigh abductors<\/em><\/p>\n

1. Gluteus<\/p>\n

2. Tensor fasciae latae<\/p>\n

b. Iliotibialis; femorotibialis, Ambiens –\u00a0Extend tibia, protract thigh<\/em><\/p>\n

1. Quadriceps<\/p>\n

2. Sartorius –\u00a0From Ambiens<\/em><\/p>\n

c. Puboischiofemoralis Internus –\u00a0Limb protractor<\/em><\/p>\n

1. Iliacus<\/p>\n

2. Psoas major<\/p>\n

3. Pectineus<\/p>\n

d. Ankle & Foot Extensors –\u00a0Course laterally<\/em><\/p>\n

2. Ventral Group<\/p>\n

a. Puboischiotibialis –\u00a0Thigh retractor; knee flexor<\/em><\/p>\n

1. Gracilis<\/p>\n

b. Pubotibialis & Flexor tibialis –\u00a0Thigh retractor; knee flexor<\/em><\/p>\n

1. Semimembranosus –\u00a0Hamstring<\/em><\/p>\n

2. Semitendinosus –\u00a0Hamstring<\/em><\/p>\n

3. Biceps femoris –\u00a0Hamstring<\/em><\/p>\n

4. Adductor longus<\/p>\n

c. Adductor femoris –\u00a0Reptiles & mammals<\/em><\/p>\n

d. Ankle & Foot flexors –\u00a0Course medially<\/em><\/p>\n

\n

H. BRANCHIOMERIC MUSCLES<\/strong><\/p>\n

1. Visceral origin; from hypomere<\/p>\n

2. Striated & Voluntary<\/p>\n

3. First Arch<\/p>\n

a. Adductor mandibulae –\u00a0Closes jaw<\/em><\/p>\n

1. Temporal<\/p>\n

2. Masseter<\/p>\n

{3. Pterygoid}<\/p>\n

b. Intermandibularis –\u00a0Raises floor of mouth<\/em><\/p>\n

1. Mylohyoid<\/p>\n

2. Digastric (anterior)<\/p>\n

3. Tensor tympani<\/p>\n

4. Second Arch<\/p>\n

a. Levator hyomandibulae –\u00a0Raises upper jaw in hyostylic suspension<\/em><\/p>\n

1. Stapedius<\/p>\n

b. Dorsal hyoid constrictor = Levator hyoideus –\u00a0Constricts pharyngeal cavity<\/em><\/p>\n

1. Stylohyoid<\/p>\n

c. Interhyoideus {ventral hyoid constrictor}<\/p>\n

1. Depressor mandibulae –\u00a0Important muscle in all vertebrates but mammals<\/em><\/p>\n

2. Digastric (posterior)<\/p>\n

3. Sphincter colli\/Platysma in mammals<\/p>\n

5. Third Arch<\/p>\n

a. Constrictors –\u00a0Dorsal & Ventral; Compresses pharynx<\/em><\/p>\n

b. Levators –\u00a0Lifts gill bars<\/em><\/p>\n

c. Adductors –\u00a0Deep; Closes internal angles of gill arch<\/em><\/p>\n

d. Interarcuals –\u00a0Expands pharynx<\/em><\/p>\n

e. a-d Stylopharyngeus –\u00a0Swallowing in Tetrapods<\/em><\/p>\n

6. Arch 4-6<\/p>\n

a. Constrictors<\/p>\n

b. Levators<\/p>\n

c. Adductors<\/p>\n

d. Interarcuals<\/p>\n

e. a-d –\u00a0Breathing & swallowing muscles<\/em><\/p>\n

-Thyroarytenoid<\/p>\n

-Cricoarytenoid<\/p>\n

-Cricothyroid<\/p>\n

f. Cucullaris– Lifts posterior gill<\/em><\/p>\n

1. Trapezius<\/p>\n

2. Sternomastoid<\/p>\n

3. Cleidomastoid<\/p>\n

See Vertebrate Muscles Page<\/a><\/strong><\/p>\n

\n

I. ELECTRIC ORGANS<\/strong><\/p>\n

1. Incidence –\u00a0Found in more than 500 species<\/em><\/p>\n

2. Derivation<\/p>\n

a. Muscle cells –\u00a0Primarily from muscle cells<\/em><\/p>\n

(b. Glandular)<\/p>\n

(c. Nervous tissue)<\/p>\n

3. Function<\/p>\n

a. Communication<\/p>\n

b. Orientation \/ objects<\/p>\n

c. Detection of prey<\/p>\n

d. Offense\/Defense<\/p>\n

4. Electroplax –\u00a0Functional unit of electric organ; modified muscle cell<\/em><\/p>\n

a. Multinucleate –\u00a0Richly innervated; numerous mitochondria<\/em><\/p>\n

b. Column –> Organ –\u00a0Columns of stacked cells, up to 10,000, comprise the electric organ<\/em><\/p>\n

c. Electric potentials –\u00a0Very high is some; Salt water eel can emit 50 Volts; Fresh water eel can emit 500 Volts.<\/em><\/p>\n

 <\/p>\n","protected":false},"excerpt":{"rendered":"

I. MUSCULAR SYSTEM A. Overall function –\u00a0Locomotion, posture, protection, heat production B. Classification 1. Skeletal\u00a0(is striated) a. Muscle fiber –\u00a0Muscle cell 1. Multinucleate 2. Myofibrils –\u00a0Striated cylinders within myofiber 3. Myofilaments –\u00a0Proteins which interlock and result in contraction a. Actin … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":270,"featured_media":0,"parent":580,"menu_order":0,"comment_status":"closed","ping_status":"open","template":"","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":""},"class_list":["post-666","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/sites.msudenver.edu\/haysc\/wp-json\/wp\/v2\/pages\/666","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sites.msudenver.edu\/haysc\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/sites.msudenver.edu\/haysc\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/sites.msudenver.edu\/haysc\/wp-json\/wp\/v2\/users\/270"}],"replies":[{"embeddable":true,"href":"https:\/\/sites.msudenver.edu\/haysc\/wp-json\/wp\/v2\/comments?post=666"}],"version-history":[{"count":0,"href":"https:\/\/sites.msudenver.edu\/haysc\/wp-json\/wp\/v2\/pages\/666\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/sites.msudenver.edu\/haysc\/wp-json\/wp\/v2\/pages\/580"}],"wp:attachment":[{"href":"https:\/\/sites.msudenver.edu\/haysc\/wp-json\/wp\/v2\/media?parent=666"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}