Microscopic and Gross Anatomy of Skeletal Muscle

Vocabulary practice flashcards covering microscopic skeletal muscle anatomy, connective tissue coverings, functional classifications, criteria for naming skeletal muscles, and gross anatomical muscle identification from Biology 232 L.

Myofilament

The contractile protein filaments in a muscle.

Actin

Protein that primarily makes up thin filaments.

Myosin

Protein that makes up thick filaments.

Sarcomere

The smallest contractile unit of a muscle.

Myofibril

Densely packed, rodlike contractile elements; each myofibril is a bundle of myofilaments.

Fascicle

A bundle of muscle fibers.

Endomysium

Connective tissue around muscle fibers (cells).

Perimysium

Connective tissue around a fascicle.

Epimysium

Connective tissue surrounding the entire muscle proper

Tendon

Cord or band of fibrous connective tissue attaching muscle to bone.

Aponeurosis

Broad sheet of connective tissue attaching muscle to muscle.

Agonist (Prime mover)

A muscle responsible for a particular action or movement (biceps brachii)

Antagonist

A muscle that produces an opposing action (triceps brachii)

Synergist

A muscle that aids in the action of another muscle (gluteus medius)

Fixator

A muscle that stabilizes a structure so that another muscle can have a fixed attachment (pectoralis minor)

Temporalis

Flat muscle overlying the temporal bone.

Epicranius

A muscle complex covering the top of the head, consisting of the frontal belly (frontalis) and occipital belly (occipitalis).

Masseter

Large muscle located at the angle (ramus) of the mandible.

Platysma

Broad, thin, superficial muscle on the anterior neck.

Zygomaticus

Thin, paired muscle running from the zygomatic bone to the corner of the mouth (smiling).

Orbicularis oris

Circular muscle surrounding the mouth that purses the lips (kissing).

Orbicularis oculi

Circular muscle surrounding the eye that tightly closes the eye (squinting).

Sternohyoid

Slender muscle running between the sternum and hyoid bone.

Internal oblique

Lateral muscle of the abdomen situated deep to the external oblique.

Transversus abdominis

The deepest of the abdominal muscles.

Intercostals

Two layers of muscle that run between the ribs.

Infraspinatus

Flat muscle that lies in the infraspinous fossa of the scapula.

Rhomboid major

Muscle that runs between the scapula and the vertebral column.

Sternohyoid, slender muscle between sternum and hyoid bone

Epicranius, a muscle complex covering top of head, has frontalis and occipitals

Occipitalis, back of head

Frontalis, forehead

Temporalis, flat muscle overlying temporal bone

Rhomboid Major, runs between the scapula and the vertebral column

Intercostals, 2 layers of muscle that run between the ribs

Transversus Abdominis, deepest of the abdominal muscles

Orbicularis Oculi, circular muscle surrounding the eyes, squinting

Orbicularis Oris, circular muscle surrounding the mouth, kiss

Infraspinatus, flat muscle that lies in the infraspinous fossa of the scapula

Internal Oblique, lateral muscle of the abdomen deep to the external oblique

Zygomaticus, thin, paired muscle running from the zygomatic bone to the corner of the mouth, smiling

Platysma, broad, thin, superficial muscle on the anterior of the neck

Masseter, large muscle at ramus of mandible