Human Anatomy and Physiology: Muscular, Nervous, and Cardiovascular Systems

Comprehensive vocabulary flashcards covering skeletal muscle anatomy, histology, cranial nerves, brain stem and diencephalon structures, and cardiac circulation.

Supraspinatus

A rotator cuff muscle originating in the supraspinous fossa of the scapula and inserting onto the greater tubercle of the humerus; it initiates abduction of the arm and stabilizes the shoulder joint.

Levator scapulae

A muscle located at the back and side of the neck deep to the trapezius, originating from the transverse processes of C1–C4 and inserting into the medial border of the scapula superior to the spine; it elevates and adducts the scapula.

Coronary circulation

The arterial and venous supply serving the myocardium of the heart, featuring the right and left coronary arteries, anterior and posterior interventricular arteries, circumflex artery, marginal arteries, cardiac veins, and the coronary sinus.

Coronary sinus

A wide venous channel located posteriorly in the coronary sulcus that receives deoxygenated blood from the great, middle, and small cardiac veins and empties directly into the right atrium.

Tibialis anterior

A superficial muscle of the anterior leg paralleling the sharp anterior margin of the tibia; acts as the prime mover of dorsiflexion, inverts the foot, and supports the longitudinal arch of the foot.

Triceps surae

A muscle pair consisting of the gastrocnemius and soleus that shapes the posterior calf and inserts via a common calcaneal tendon into the calcaneus of the heel to plantar flex the foot.

Calcaneal tendon

The large tendon of the posterior leg that connects the triceps surae (gastrocnemius and soleus) directly to the calcaneus bone of the heel.

Iliopsoas

A composite muscle group comprising the iliacus and psoas major located in the pelvis and upper thigh that functions as a prime mover for flexing the thigh.

Apical impulse

The heartbeat pulsation felt or visualized on the thoracic wall at the location where the apex of the heart contacts the chest wall.

Chordae tendineae

Tiny, tendon-like collagen cords that attach the cusps of the atrioventricular (tricuspid and mitral) valves to the papillary muscles of the ventricular myocardium.

Erector spinae

The deep muscle mass of the back comprising three columns (iliocostalis, longissimus, and spinalis) that provides primary resistance to spinal flexion and extends the vertebral column.

Triad (muscle fiber)

A three-part structure in skeletal muscle fibers formed by a central transverse (T) tubule flanked on each side by two terminal cisterns of the sarcoplasmic reticulum.

Sarcolemma

The plasma membrane surrounding an individual skeletal muscle fiber (cell).

Flexor digitorum profundus

A deep muscle of the anterior forearm overlain by the flexor digitorum superficialis; it serves as the sole muscle that flexes the distal phalanges of fingers II–V and assists in hand flexion.

Pronator quadratus

The deepest muscle of the distal anterior forearm, running from the distal ulna to the distal radius, responsible for forearm pronation.

Brain stem

The stalklike inferior region of the brain consisting of three major structures: the midbrain, pons, and medulla oblongata.

Corpora quadrigemina

Four rounded elevations located on the posterior aspect of the midbrain comprising the paired superior colliculi (visual reflex centers) and paired inferior colliculi (auditory reflex centers).

Neuromuscular junction

The specialized synaptic connection between an axon terminal of a motor neuron and the junctional folds of a skeletal muscle fiber's sarcolemma across the synaptic cleft.

Linea alba

A narrow tendinous sheath running vertically along the midline of the anterior abdominal wall from the sternum to the pubic symphysis, formed by the fusion of the aponeuroses of the oblique and transversus muscles.

Transversus abdominis

The deepest muscle layer of the anterior abdominal wall whose fibers run horizontally to compress the abdominal contents.

Masseter

A muscle covering the lateral aspect of the mandibular ramus that originates on the zygomatic arch and bone and inserts onto the mandibular angle and ramus; serves as the prime mover of jaw closure.

Lateral pterygoid

A deep muscle of mastication originating from the greater wing of the sphenoid bone and inserting on the condylar process of the mandible; protracts the jaw and aids in grinding movements of the teeth.

Skeletal muscle histology

Microscopic appearance of skeletal muscle tissue displaying long, cylindrical, multinucleated fibers with alternating light (I) and dark (A) transverse striations in longitudinal and cross-sectional views.

Fossa ovalis

A shallow depression located in the interatrial septum of the right atrium that represents the remnants of the fetal foramen ovale.

Trabeculae carneae

Irregular muscular ridges and bridges lining the internal surfaces of the right and left ventricular walls.

Popliteus

A flat, thin muscle located deep in the posterior compartment of the leg directly beneath the knee joint, superior to the origin of the flexor digitorum longus and tibialis posterior.

Triceps brachii

A large three-headed fleshy muscle of the posterior humerus that inserts into the olecranon of the ulna to serve as a powerful forearm extensor.

Biceps brachii

A two-headed muscle on the anterior humerus that inserts into the radial tuberosity; acts as a powerful flexor and supinator of the forearm ('turns the corkscrew and pulls the cork').

Trigeminal nerve (Cranial Nerve V)

A large mixed cranial nerve containing ophthalmic, maxillary, and mandibular divisions that provides sensory input from the face, scalp, and eye surfaces, and motor control to the muscles of mastication.

Glossopharyngeal nerve (Cranial Nerve IX)

A mixed cranial nerve emerging from the medulla oblongata that supplies somatic motor fibers to pharyngeal muscles, parasympathetic motor fibers to salivary glands, and conducts taste from the posterior third of the tongue.

Fascicle arrangement patterns

The structural alignments of skeletal muscle fascicles, classified into circular, convergent, fusiform, parallel, multipennate, bipennate, and unipennate patterns.

Pulmonary circuit

The pathway of cardiovascular circulation that routes oxygen-poor, carbon dioxide-rich blood from the right ventricle to the capillary beds of the lungs and returns oxygen-rich blood via pulmonary veins to the left atrium.

Extensor digiti minimi

A slender superficial muscle situated on the posterior compartment of the forearm that extends the fifth digit (little finger).

Extensor retinacula

Broad fibrous bands of connective tissue across the anterior ankle (superior and inferior) that hold the extensor tendons close to the ankle joints during dorsiflexion.

Zygomaticus (major and minor)

A pair of facial muscles running diagonally from the cheekbone to the corner of the mouth that raises the lateral corners of the mouth upward during smiling.

Platysma

An unpaired, thin sheetlike superficial neck muscle originating from chest fascia that tenses the skin of the neck, depresses the mandible, and pulls the lower lip inferiorly.

Rectus femoris

A superficial muscle of the anterior thigh belonging to the quadriceps group; the only quadriceps muscle crossing both the hip and knee joints to extend the leg and flex the thigh.

Gluteus maximus

The largest and most superficial gluteal muscle of the pelvis; functions as a powerful thigh extensor (notably when climbing stairs), abductor, and lateral rotator.

Digastric

A suprahyoid muscle composed of two bellies united by an intermediate tendon; acts to elevate the hyoid bone, open the mouth, and depress the mandible.

Omohyoid

A two-bellied straplike infrahyoid muscle located lateral to the sternohyoid that acts to depress the hyoid bone and larynx.

Purkinje cells

Large, multipolar neurons situated in the cerebellar cortex featuring an extensively branched, fan-like dendritic tree.

Dorsal root ganglion cells

Unipolar sensory neuron cell bodies characterized by a rounded shape, clustered in ganglia along dorsal nerve roots and bordered by satellite neuroglial cells.

Fornix

An arching bandlike fiber tract located inferior to the corpus callosum that connects limbic system structures and is involved in olfaction.

Septum pellucidum

A thin, vertical membranous partition located beneath the corpus callosum that separates the two lateral ventricles of the cerebral hemispheres.

Arbor vitae

The distinctive branched, tree-like pattern of white matter seen in a midsagittal section of the cerebellum.

Latissimus dorsi

A broad, flat muscle of the lower back and lumbar region that acts as the prime mover of arm extension, and brings the arm down in a powerful stroke during adduction and medial rotation.

Palmaris longus

A superficial muscle of the anterior forearm with a small fleshy belly and a long tendon inserting into the palmar aponeurosis; provides weak hand flexion and tenses the palmar fascia.