Muscular System: Histology, Connective Tissues, and Muscle Actions

Vocabulary practice flashcards covering muscle histology types, connective tissue coverings, and specific muscle names with their anatomical actions across body regions.

Cardiac Muscle

An involuntary, striated muscle tissue found in the heart with short, branching cells, a single nucleus per cell, and junctions tightly bound by intercalated discs; responsible for pumping blood.

Intercalated Discs

Structures that tightly bind cardiac muscle cells together at their junctions.

Smooth Muscle

An involuntary, non-striated muscle tissue made of closely crowded, spindle-shaped cells with a single nucleus; found inside hollow organs to provide movement necessary for their functions.

Skeletal Muscle

A voluntary muscle tissue attached to the skeleton, composed of long, fiber-like cells with multiple nuclei and striations formed by the A and I bands on myofibrils; controlled consciously.

Epimysium

A supportive connective tissue layer that surrounds the entire skeletal muscle.

Perimysium

A supportive connective tissue layer that surrounds a muscle fascicle.

Endomysium

A supportive connective tissue layer that surrounds an individual muscle fiber.

Inferior Rectus

An extrinsic eye muscle that moves the eyeball down.

Lateral Rectus

An extrinsic eye muscle that moves the eyeball lateral.

Superior Oblique

An extrinsic eye muscle that produces downward and outward rotation of the eyeball.

Inferior Oblique

An extrinsic eye muscle that produces upward and outward rotation of the eyeball.

External Abdominal Oblique

An abdominal wall muscle that causes flexion and rotation of the trunk, compression of the abdominal viscera, and expiration.

Internal Abdominal Oblique

An abdominal wall muscle that produces flexion and rotation of the trunk, compression of the abdominal viscera, and expiration.

Transversus Abdominis

An abdominal wall muscle responsible for rotation of the trunk, compression of the abdominal viscera, expiration, and urination.

Rectus Abdominis

An abdominal wall muscle that causes flexion of the trunk, compression of the abdominal viscera, and expiration.

Linea Alba

A tendinous structure (not a muscle) that anchors the abdominal muscles.

Diaphragm

A muscle for breathing that pushes abdominal contents down during inspiration.

External Intercostal Muscles

Muscles for breathing that raise and spread the ribs during inspiration.

Internal Intercostal Muscles

Muscles for breathing active in forced expiration only.

Levator Ani

A muscle of the pelvic floor that controls bowel elimination.

Coccygeus Muscle

A pelvic floor muscle that controls bowel elimination.

External Anal Sphincter

A muscle of the pelvic floor responsible for controlling bowel elimination.

Trapezius

A muscle acting on the scapula whose upper portion elevates and lower portion depresses the scapula.

Serratus Anterior

A muscle acting on the scapula that rotates it.

Pectoralis Minor

A muscle acting on the scapula that pulls it anteriorly.

Levator Scapulae

A muscle that elevates the scapula.

Rhomboideus Major

A muscle acting on the scapula that elevates and adducts it.

Rhomboideus Minor

A muscle acting on the scapula that elevates and adducts.

Pectoralis Major

A muscle acting on the humerus at the shoulder joint that flexes, adducts, and medially rotates the humerus.

Latissimus Dorsi

A muscle acting on the humerus at the shoulder joint that extends, adducts, and medially rotates the humerus.

Deltoid

A muscle acting on the humerus at the shoulder joint that abducts the arm.

Supraspinatus

A muscle acting on the humerus at the shoulder joint that abducts the humerus.

Infraspinatus

A muscle acting on the humerus at the shoulder joint that laterally rotates the humerus.

Subscapularis

A muscle acting on the humerus at the shoulder joint that medially rotates the humerus.

Teres Major

A muscle acting on the humerus at the shoulder joint that extends, adducts, and medially rotates the humerus.

Teres Minor

A muscle acting on the humerus at the shoulder joint that laterally rotates the humerus.

Coracobrachialis

A muscle acting on the humerus at the shoulder joint that flexes and adducts the humerus.

Brachialis

A muscle acting on the forearm at the elbow joint that flexes the forearm.

Brachioradialis

A muscle acting on the forearm at the elbow joint that flexes the forearm.

Biceps Brachii

A muscle acting on the forearm at the elbow joint that flexes and supinates the forearm.

Triceps Brachii

A muscle acting on the forearm at the elbow joint that extends the forearm.

Supinator

A deep muscle acting on the forearm at the elbow joint that supinates the forearm.

Pronator Teres

A muscle acting on the forearm at the elbow joint that pronates the forearm.

Flexor Carpi Radialis

A muscle acting on the wrist joint that flexes and abducts the hand at the wrist.

Flexor Carpi Ulnaris

A muscle acting on the wrist joint that flexes and adducts the hand at the wrist.

Extensor Carpi Radialis

A muscle acting on the wrist joint that extends and abducts the hand at the wrist.

Extensor Carpi Ulnaris

A muscle acting on the wrist joint that extends and adducts the hand at the wrist.

Palmaris Longus

A muscle acting on the wrist joint that flexes the wrist.

Flexor Digitorum Superficialis

A muscle acting on the fingers that flexes the fingers.

Extensor Digitorum

A muscle acting on the fingers that extends the fingers.

Iliopsoas

A muscle formed from the merger of the iliacus and psoas major that flexes the femur at the hip joint.

Gluteus Maximus

A muscle acting on the femur at the hip joint that causes extension and lateral rotation.

Gluteus Medius

A muscle acting on the femur at the hip joint that produces abduction and medial rotation.

Adductor Longus

A muscle acting on the femur at the hip joint that adducts and flexes the femur.

Adductor Magnus

A muscle acting on the femur at the hip joint that adducts and flexes the femur.

Pectineus

A muscle acting on the femur at the hip joint that adducts, flexes, and medially rotates the thigh.

Tensor Fasciae Latae

A muscle connected to the tibia via the iliotibial band that abducts and medially rotates the thigh at the hip joint.

Gracilis

A long muscle of the thigh that crosses two joints to flex the knee and adduct the femur.

Sartorius

A long muscle of the thigh crossing two joints that flexes the knee and femur, and laterally rotates the femur.

Rectus Femoris

A quadriceps femoris muscle that flexes the thigh at the hip and extends the leg at the knee.

Vastus Lateralis

A quadriceps femoris muscle that flexes the thigh at the hip and extends the leg at the knee.

Vastus Intermedius

A deep quadriceps femoris muscle that flexes the thigh at the hip and extends the leg at the knee.

Vastus Medialis

A quadriceps femoris muscle that flexes the thigh at the hip and extends the leg at the knee.

Semitendinosus

A medial and superficial hamstring muscle crossing two joints that flexes the leg and extends the thigh.

Semimembranosus

A medial and deep hamstring muscle crossing two joints that flexes the leg and extends the thigh.

Biceps Femoris

A lateral hamstring muscle crossing two joints that flexes the leg and extends the thigh.

Gastrocnemius

A muscle acting on the foot at the ankle joint that plantar flexes the foot.

Soleus

A muscle acting on the foot at the ankle joint that plantar flexes the foot.

Tibialis Anterior

A muscle acting on the foot at the ankle joint that dorsiflexes the foot.

Fibularis Longus

A muscle acting on the foot at the ankle joint that everts the foot.

Fibularis Brevis

A muscle acting on the foot at the ankle joint that everts the foot.

Extensor Digitorum Longus

A muscle acting on the foot at the ankle joint that serves as the prime mover of toe extension and dorsiflexes the foot.

Flexor Digitorum Longus

A muscle acting on the foot that plantar flexes and inverts the foot, flexes the toes, and helps footgrip the ground.