Chapter 11 – The Muscular System: Key Concepts and Major Muscles

A set of 50 question-and-answer flashcards covering core principles of muscle mechanics, naming conventions, major skeletal muscles, and common disorders from Chapter 11 of Tortora & Derrickson’s Principles of Anatomy and Physiology.

What structure attaches a skeletal muscle to a stationary bone?

The origin

What name is given to the attachment of a muscle on the moveable bone?

The insertion

In a first-class lever, what lies between the effort and the load?

The fulcrum

Which class of lever always provides a mechanical advantage in force production?

Second-class lever

Which lever class is most common in the body and favors speed and range of motion?

Third-class lever

What fascicle arrangement forms sphincter muscles that close an orifice?

Circular arrangement

Which fascicle pattern tapers at both ends, giving a spindle shape?

Fusiform

Name the fascicle arrangement in which fibers run on only one side of a tendon.

Unipennate

Which fascicle arrangement has fibers on both sides of a central tendon?

Bipennate

What is the function of an agonist (prime mover) in a muscle group?

It produces the primary action for a specific movement

How does an antagonist muscle contribute to movement?

It opposes and controls the action of the agonist

What role does a synergist play during joint movement?

It assists the agonist by adding force or stabilizing the joint

Muscles named ‘rectus’ have fibers oriented in what direction relative to the midline?

Parallel to the midline

What term designates the largest muscle among a group, as in ‘gluteus maximus’?

Maximus

Which shape term is used for a triangular muscle such as the deltoid?

Deltoid

A muscle whose name ends in ‘-flexor’ performs what primary action?

It decreases the angle of a joint (flexion)

How many origins does a muscle prefixed with ‘triceps’ have?

Three origins

What muscle is named for its proximity to the temporal bone?

Temporalis

Which facial muscle closes and protrudes the lips for kissing or whistling?

Orbicularis oris

What is the strongest muscle of mastication that elevates the mandible?

Masseter

Which three paired muscles precisely move each eye?

Superior & inferior recti, lateral & medial recti, and superior & inferior obliques

Name the muscle that flexes and rotates the head and is abbreviated SCM.

Sternocleidomastoid

Which chest muscle adducts and medially rotates the arm at the shoulder joint?

Pectoralis major

What shoulder muscle abducts, flexes, and medially rotates the arm?

Deltoid

Which large back muscle draws the arm inferiorly and posteriorly and is called the swimmer’s muscle?

Latissimus dorsi

Identify the paired anterior abdominal muscle known as the “six-pack.”

Rectus abdominis

Which abdominal muscle has fibers that run diagonally and aids in trunk rotation?

External oblique

What dome-shaped muscle is the primary muscle of inspiration?

Diaphragm

Which arm muscle flexes and supinates the forearm at the elbow joint?

Biceps brachii

What is the primary elbow extensor that opposes the biceps brachii?

Triceps brachii

Name the muscle on the lateral forearm that is most effective at mid-pronation flexion.

Brachioradialis

Which intrinsic hand region is located on the thumb side of the palm?

Thenar region

What small hand muscle allows opposition of the thumb?

Opponens pollicis

Which large gluteal muscle extends and laterally rotates the thigh at the hip?

Gluteus maximus

Name the four-muscle group that extends the leg at the knee and flexes the thigh.

Quadriceps femoris (rectus femoris, vastus lateralis, vastus medialis, vastus intermedius)

What three-muscle group flexes the knee and extends the hip, enabling walking and running?

Hamstrings (biceps femoris, semitendinosus, semimembranosus)

Which anterior leg muscle dorsiflexes and inverts the foot?

Tibialis anterior

Name the two muscles that share the Achilles tendon to plantar flex the foot.

Gastrocnemius and soleus

What condition involves painful inflammation of the plantar aponeurosis at the calcaneus?

Plantar fasciitis

Define compartment syndrome in muscular compartments.

Increased pressure that constricts tissues, risking nerve damage and muscle contracture

What acronym summarizes the immediate treatment for most running injuries?

PRICE – Protection, Rest, Ice, Compression, Elevation

Which lever type is exemplified by raising the head on the vertebral column?

First-class lever

Rising onto your toes (gastrocnemius action) demonstrates which lever class?

Second-class lever

Flexing the forearm with the biceps brachii uses what lever class?

Third-class lever

Which fascicle pattern converges from a broad origin to a single tendon, giving a fan shape?

Triangular (convergent) arrangement

Muscles with fibers running parallel to a long tendon on many sides are classified as what type of pennate?

Multipennate

The term ‘vastus’ in muscle nomenclature refers to what size characteristic?

Huge or vast size

What is the common insertion point for the quadriceps femoris via the patellar ligament?

Tibial tuberosity

Which muscle group elevates the hyoid bone during swallowing and speech?

Suprahyoid muscles

Name the primary nerve that innervates the diaphragm.

Phrenic nerve (C3–C5)