Lecture 11 Muscular System Lecture Review

Flashcards covering the structure, function, coordination, naming, and specific muscles of the human muscular system based on lecture notes.

How do skeletal muscles produce movement?

By exerting force on tendons which then pull on bones.

What is the origin of a muscle?

The attachment point to the stationary bone.

What is the insertion of a muscle?

The attachment point to the moveable bone.

What happens when a muscle contracts in relation to its origin and insertion?

It draws the moveable (insertion) bone toward the stationary (origin) bone.

Which type of muscle is the principal muscle involved with a specific movement?

Prime mover or agonist.

What is the role of an antagonistic muscle?

It relaxes when the prime mover contracts, allowing movement.

What is the function of synergistic muscles?

They contract at the same time to assist the prime mover, causing movement in the same direction.

What are some criteria used for naming muscles?

Location, size, number of origins, appearance, direction of fibers, origin and insertion, or muscle action.

What connective tissue surrounds an entire muscle?

Epimysium.

What connective tissue surrounds muscle fascicles?

Perimysium.

What connective tissue surrounds individual muscle fibers (cells)?

Endomysium.

What are the contractile units within a myofibril, extending from Z line to Z line?

Sarcomeres.

What two factors are correlated with the fascicular arrangement of a muscle?

The amount of power a muscle can produce and its range of motion.

In which fascicle arrangement are muscle fascicles parallel to the longitudinal axis?

Parallel.

What are the three types of pennate fascicle arrangements?

Unipennate, Bipennate, and Multipennate.

What type of fascicle arrangement is exemplified by the biceps brachii and rectus abdominis?

Parallel.

What type of fascicle arrangement is exemplified by the deltoid muscle?

Multipennate.

What are two methods to describe muscle actions?

Reference to the bone region the muscle is associated with, or reference to a specific joint the muscle is associated with.

What are the two main divisions for identifying skeletal muscles?

Axial and Appendicular.

What do axial muscles refer to?

Muscles of the trunk and head.

Where do muscles of facial expression typically insert?

Into the skin rather than a bone or joint.

What are the muscles that move the eyeballs called?

Extrinsic eye muscles.

How many extrinsic eye muscles are there in total?

Six (three pairs).

Name one pair of extrinsic eye muscles.

Superior and inferior recti (or Lateral and medial recti, or Superior and inferior obliques).

Name two muscles involved in mastication (chewing).

Temporalis and Masseter (or Lateral pterygoid, Medial pterygoid).

What bone do suprahyoid and infrahyoid muscles relate to, assisting in deglutition and speech?

Hyoid bone.

Name one suprahyoid muscle.

Geniohyoid (or Digastric, Mylohyoid, Stylohyoid).

Name one infrahyoid muscle.

Thyrohyoid (or Omohyoid, Sternohyoid, Sternothyroid).

Which muscle serves as an important landmark, dividing the sides of the neck into anterior and posterior triangles?

Sternocleidomastoid.

What two bones form the articulation point for the head with the vertebral column?

Atlas and occipital bone.

How many layers of muscles compose the anterolateral abdominal wall?

Six.

What is considered the most important respiratory muscle?

The diaphragm.

Name two muscles of the thorax that assist in breathing.

Diaphragm, External Intercostals, or Internal Intercostals.

What is an important function of muscles that move the pectoral girdle, besides movement?

Stabilizing the scapula.

How does scapular movement contribute to arm function?

It increases the range of motion of the humerus.

What is the primary function of the muscles forming the rotator cuff?

To strengthen and stabilize the shallow shoulder joint.

How many deep shoulder muscles make up the rotator cuff?

Four.

Name two muscles that cause flexion at the elbow.

Biceps brachii, Brachialis, or Brachioradialis.

Name the primary muscle responsible for extension at the elbow.

Triceps brachii.

Name a muscle responsible for pronation of the forearm.

Pronator teres or Pronator quadratus.

What muscle is solely responsible for supination of the forearm?

Supinator.

What are the strong fascial bands that hold the tendons of extrinsic hand muscles close to the bones at the wrist?

Retinacula.

What general action do anterior extrinsic muscles of the forearm perform on the wrist, hand, thumb, and fingers?

Flexion.

What general action do posterior extrinsic muscles of the forearm perform on the wrist, hand, thumb, and fingers?

Extension.

What is the primary action of the erector spinae muscles on the vertebral column?

Extension.

Name the three groups of erector spinae muscles.

Iliocostalis, Longissimus, and Spinalis.

What is the chief extensor of the femur?

Gluteus maximus.

What is the primary action of the gluteus medius muscle?

Abduction of the femur.

Which muscle group is responsible for extending the leg and includes the rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius?

Quadriceps femoris group.

Which muscle group is responsible for flexing the leg and includes the biceps femoris, semitendinosus, and semimembranosus?

Hamstrings.