Muscular System: Sarcomere Anatomy and Muscles of the Neck, Shoulder, Back, and Gluteal Region

Flashcards testing knowledge of sarcomere anatomy, neuromuscular junctions, and the names, locations, and actions of superficial and deep muscles from the neck to the gluteal region.

What key cellular interface is introduced alongside the Structure of a Sarcomere in the lecture diagrams?

Neuromuscular Junction

What are the primary myofilament types that compose a myofibril and sarcomere?

Thick Myosin Filament and Thin Actin Filament

What specific bands, zones, and boundary lines are identified within the structure of a sarcomere?

Z Disc, M Line, I Band, A Band, and H Zone

Which four muscles comprise the rotator cuff "SITS" muscle group?

Supraspinatus, Infraspinatus, Teres minor, and Subscapularis

Which rotator cuff muscle is explicitly noted as not being shown in either the table or the illustration?

Subscapularis

What anatomical landmarks and associated structures are labeled alongside the superficial and deep back muscles?

Spine of scapula, Triceps brachii, Lumbodorsal fascia, and Iliac crest

What are the actions of the Sternocleidomastoid?

Simultaneous contraction of both muscle heads flexes the neck forward; individual action of each muscle head rotates the head to the shoulder on the opposite side.

What are the actions of the Trapezius?

Elevates, retracts, depresses, or rotates scapula upward; elevates.

What are the actions of the Deltoid?

Flexes, extends, abducts; medial and laterally rotates arm.

What is the action of the Infraspinatus?

Abducts and laterally rotates arm

What is the action of the Teres minor?

Adducts, extends, and laterally rotates arm

What is the action of the Teres major?

Extends, medially rotates, and adducts arm

What is the action of the Latissimus dorsi?

Extends, adducts, and medially rotates arm

What are the actions of the External oblique?

Compresses anterior abdominal wall; flexes trunk; rotates trunk; depresses lower ribs on.

What is the action of the Gluteus medius?

Abducts and medially rotates hip

What is the action of the Gluteus maximus?

Extends and laterally rotates hip

What is the action of the Semispinalis capitis?

Extends head and rotates to opposite side

What is the action of the Splenius capitis?

Extends and hyperextends the head

What are the actions of the Levator scapulae?

Elevates scapula and draws it medially; with scapula fixed, flexes neck laterally to same side.

What is the action of the Rhomboid minor?

Retracts, adducts, and stabilizes the scapula

What are the actions of the Rhomboid major?

Adducts, retracts, elevates, and rotates scapula; stabilizes scapula.

What are the actions of the Supraspinatus?

Abducts arm; stabilizes shoulder joint

What is the action of the Serratus anterior?

Abducts and stabilizes scapula

What is the action of the Serratus posterior inferior?

Depresses last four ribs

What are the actions of the Internal oblique?

Compresses anterior abdominal wall; flexes trunk; rotates trunk; depresses lower ribs.