Ex. 12: Skeletal Muscle 1. A. Characteristics of Three Muscle Types 2.

Ex. 12: Skeletal Muscle

1

A. Characteristics of Three Muscle Types

2

1. Skeletal muscle– with striations; each skeletal muscle cell (fiber) has multiple and peripherally located nuclei

3

Striations Muscle fiber

(b)

(a)

Nuclei

Location– primarily to bones by tendons

4

2. Cardiac muscle–striations; each muscle cell (fiber) has a single centrally located nucleus, branches, and intercalated discs at both ends

5

Location– the heart

6

3. Smooth muscle– without striations; each cell (fiber), with a single and centrally located nucleus, is thick in the middle and tapered at each end

7

Muscle cellsNuclei

(b)

(a)

Location– walls of viscera, airways, blood vessels, iris and ciliary body of eye

8

B. The Organization of Skeletal Muscle

9

10

A

B

C

C. The Neuromuscular Junction

14

Skeletalmusclefibers

Neuromuscularjunction

Motorneuron 2

Spinal cord

Motorneuron 1

The number of muscle fibers controlled by one neuron is called a motor unit.

15

Neurotransmitter

16

Ex. 13: Gross Anatomy of the

Muscular System

17

Required muscles/tendons are highlighted in green, the same 80 muscles and 3 tendons appeared in the lab manual.

When highlighted in red, muscles’ actions, insertions, and origins are also required.

Frontalis

Galea aponeurotica

Orbicularis oculi

Platysma

Anterior view

Mentalis (cut)

Orbicularis oris

MasseterZygomaticus minor

Levator labii superioris

Zygomaticus majorRisorius

Depressor anguli oris

Depressor labii inferioris

Nasalis

Corrugator supercilii

BuccinatorModiolus

Levator anguli oris

Superficial Deep

18

Temporalis

Frontalis (cut)Galea aponeurotica

Orbicularis oculi

Sternohyoid

Orbicularis oris

Occipitalis

OmohyoidSternothyroid

Inferior pharyngealconstrictor

Sternocleidomastoid

Masseter

Thyrohyoid

Zygomatic arch


Zygomaticus minor

Zygomaticus major

Depressor labiiinferioris


Buccinator

Risorius (cut)

Nasalis


Mentalis

Levator scapulae

Lateral view

Modiolus

19

O: Zygomatic arch & maxilla; I: Mandibular angle & ramus

Action: Closes jaw & elevates mandible

Galea aponeurotica

Inferior pharyngealconstrictor

Thyrohyoid

Zygomatic arch


Depressor labiiinferioris


Nasalis


Levator scapulae

Lateral view

Modiolus

20

Origin: Insertion: Action:

Practice

Levator scapulae

Sternocleidomastoid

Digastric:Anterior bellyPosterior belly

StylohyoidMylohyoid

Sternohyoid

Suprahyoidgroup

Infrahyoidgroup

Anterior view

Hyoid bone

Common carotid artery

Internal jugular vein

Clavicle

Thyrohyoid

Omohyoid:Superior bellyInferior belly

Sternothyroid

Superficial Deep

Infrahyoidgroup

21

O: Manubrium & medial clavicle; I: Mastoid process of temporal bone

Action: Flexion in neck against resistance

Trapezius

Splenius capitis

Sternocleidomastoid

Levator scapulae

Scalenes

Omohyoid (inferior belly)

Stylohyoid

Mylohyoid

HyoglossusDigastric (posterior belly)

Thyrohyoid

Hyoid bone

Inferior pharyngeal constrictor

Sternohyoid

Lateral view

Omohyoid(superior belly)

Digastric(anterior belly)

Sternothyroid

22

Trapezius:O: Occipital bone, spine of C7

& all thoracic vertebrae; I: Acromion & spinous process of scapula

Action: Extends heads, movement of scapula

Splenius capitis

Levator scapulae

Scalenes

Hyoglossus

Thyrohyoid

Hyoid bone

Inferior pharyngeal constrictor

Lateral view

Sternothyroid

23

Origin: Insertion:

Action:

Practice

Pectoralis major

Tendinousintersections

Linea alba

Latissimus dorsi

Rectus abdominisInguinal ligament

Rectus sheath (cut edges)

Serratus anterior

Aponeurosis of external abdominal oblique

Umbilicus

Linea semilunaris

Transverse abdominal

Internal abdominaloblique (cut)

External abdominaloblique (cut)

Rectus sheath

Superficial muscles of the anterior abdominal wall

24

Subclavius

Pectoralis minor (cut)

Internal intercostals

External intercostals

Rectus abdominis (cut)

External abdominaloblique (cut)

Internal abdominaloblique (cut)

Transverse abdominal (cut)

Posterior wall of rectus sheath(rectus abdominis removed)

Internal abdominaloblique

Inguinal ligament

Rectus sheath

Serratus anterior

Pectoralis minor

25

Deep muscles of the anterior abdominal wall

Subclavius

External intercostals

Posterior wall of rectus sheath(rectus abdominis removed)

Inguinal ligament

Rectus sheath

26

Deep muscles of the anterior abdominal wall

Practice

O: Xiphoid processof sternum

Esophagus

Inferior vena cava

Insertion: Centraltendon

of diaphragm

Externalintercostals

Internalintercostals

Lateral view of intercostal muscles

Inferior view of diaphragm

O: Vertebralcolumn

O: Ribs

27

Action: Prime mover of

inspiration

Sternocleidomastoid

Deltoid

Latissimus dorsi

Thoracolumbar fascia

External abdominal oblique

Levator scapulae

Rhomboideus major/minor

Infraspinatus

Teres minor

Internal abdominal oblique

Gluteus maximus

Gluteus medius Gluteus minimus

Lateral rotators

Serratus posterior inferior

Serratus anterior

Supraspinatus

Erector spinae

Splenius capitis

Teres major

External abdominal oblique

Trapezius

Superficial Deep

28

Neck, back, and gluteal muscles

O: Acromion and spine of scapulaI: Deltoid tuberosity

Action: Prime mover of arm abduction

Thoracolumbar fascia

Lateral rotators

Serratus posterior inferior

Erector spinae

Splenius capitis

Superficial Deep

29

Neck, back, and gluteal muscles

Origin: Insertion:

Action:

Practice

Clavicle

Deltoid

Sternum

Pectoralis major

CoracobrachialisTriceps brachii:

Anterior view

Long headMedial head

Biceps brachii

Brachialis

Brachioradialis

Lateral head

30

Posterior view

SupraspinatusSpine of scapula

Greater tubercleof humerus

Infraspinatus

Teres minor

Teres major

Triceps brachii:Lateral head

Long head

Latissimus dorsi

Humerus

O: glennoid cavityI: olecranon process of ulnaAction: forearm extensor

31

Brachialis

Subscapularis

Coracobrachialis

Anterior view

O: Distal humerus I: coronoid process of ulna Action: Major flexor of forearm

32

(c) Deep flexors(b) Intermediate flexor(a) Superficial flexors

Flexordigitorum

superficialis

Flexordigitorumprofundus

Supinator

Flexorpollicislongus

Biceps brachii

Brachialis

Pronator teres

Brachioradialis

Flexor carpi radialis

Palmaris longus

Flexor digitorumsuperficialis

Extensor carpi radialislongus and brevis

Triceps brachii

Common flexor tendon

Aponeurosis of bicepsbrachii

Flexor carpi ulnaris

Interosseousmembrane

Flexorpollicis longus

Flexordigitorumsuperficialistendons

Flexordigitorumprofundustendons

Common flexortendon

Palmaraponeurosis



Flexorretinaculum

Anterior view

33

Anterior view of the forearm

(c) Deep flexors(b) Intermediate flexor(a) Superficial flexors

Flexordigitorumprofundus

Common flexor tendon

Aponeurosis of bicepsbrachii

Interosseousmembrane



Common flexortendon

Palmaraponeurosis



Flexorretinaculum

Anterior view

34

Anterior view of the forearm

Practice

Anconeus

Supinator

Abductor pollicislongus

Extensor pollicislongus

Extensor pollicisbrevis

Extensor indicis

Olecranon

Tendons of extensordigitorum

(a) Superficial extensors (b) Deep extensors

Posterior view

Extensor carpiulnaris

Anconeus

Triceps brachii

Flexor carpiulnaris

Extensor digitiminimi

Tendon ofextensor indicis

Extensor carpiradialis longus

Extensor carpiradialis brevis

Extensor digitorum

Abductor pollicislongus

Extensor pollicisbrevis

Extensor pollicislongus

Brachioradialis

Tendons of extensorcarpi radialis longusand brevis

35

Posterior view of the forearm

Medial epicondyle

Lateral epicondyle

Ulna

Pronator quadratus

Pronator teres

Supinator

Radius

Radius

Supination

Muscle actionsin supination

Pronation

Ulna

Bursa

Bicepsbrachii

Supinator

36

Iliac crest

Iliopsoas: includes

Iliacus

Anterior superior iliac spine

Iliotibial band

Anterior muscles of thigh, superficial view

SartoriusRectus femoris

Vastus lateralis

Vastus medialis

Quadriceps femoris tendon

Patella

Patellar ligament

Adductor magnus

Gracilis

Adductor longus

Pectineus

Medial compartment:

L5

Adductor brevis

Anterior compartment:

Tensor fasciae latae

Psoas major

37

O: Iliac spine and superior acetabulumI: Tibial tuberosity and patellaAction: Extend knee and flexes thigh at hip

Iliac crest

Iliacus

Anterior superior iliac spine

Anterior muscles of thigh, superficial view


Patella

Patellar ligament

Pectineus

Medial compartment:

L5

Adductor brevis

Anterior compartment:

Tensor fasciae latae

Psoas major

38

Origin:

Insertion:

Action:

Practice

includes

Quadriceps femoris:

Vastus lateralis

Vastus medialis


Patella

Patellar ligament

Vastus intermedius

Anterior muscles of the thigh, deep view

39

Gluteusminimus

Quadratusfemoris

Piriformis

Gemellussuperior

Obturatorinternus

Gemellusinferior

Sacrum

Gluteusmaximus

Coccyx

Ischialtuberosity

Iliac crest

Obturatorexternus

Lateral rotators:

Superficial Deep

Gluteusmedius

Gluteal muscles, posterior view

40

Gluteus medius

Gluteus maximus

Iliotibial band

Short head

Biceps femoris, long head

Hamstring group:

Semitendinosus

Semimembranosus

Adductor magnus

Gracilis

Vastus lateralis

Posterior muscles of the hip and thigh

Biceps femoris, long head: O: Ischial tuberosityI: Head of fibula & lateral condyle of tibiaAction: Extends thigh, laterally rotates leg, & flexes knee

41

Short head

Hamstring group:

Posterior muscles of the hip and thigh

Origin:

Insertion:

Action:

42Practice

(a)

Patellar ligament

Fibularis longus

Fibularis brevis

Extensor digitorum longus

Tibialis anterior

Patella

Tibia

Gastrocnemius

Soleus

Extensor retinacula

43

O: Lateral condyle of tibiaI: First cuneiform and metatarsal 1Action: Prime mover of dorsiflexion

Extensorhallucislongus

Fibularis tertius

(c) 44

(d)

Extensor digitorum longus

45

Gastrocnemius:

Calcaneal tendon

Calcaneus

Medial head

Lateral head

Plantaris

Tendon of gastrocnemius

Superficial muscles of the leg, posterior compartment

46

Heads of gastrocnemius (cut)

Popliteus

Flexor digitorum longus

Plantaris

Soleus

Flexor hallucis longus

Tendon of plantaris

Fibularis brevis

Fibularis longus

Fibularis longus

Gastrocnemius (cut)

Deep muscles of the leg, posterior view

47

Calcaneal tendon (cut)

Calcaneus

(a)

Flexor digitorum longus

Flexor hallucis longus

Popliteus

Plantaris (cut)

Soleus (cut)

Fibula

Fibularis longus

Fibularis brevis

Gastrocnemius (cut)

Tibialis posterior

48

Ex. 12: Skeletal Muscle 1. A. Characteristics of Three Muscle Types 2.

Documents

Transcript of Ex. 12: Skeletal Muscle 1. A. Characteristics of Three Muscle Types 2.