Muscle Anatomy Lecture Review

A set of Question-and-Answer flashcards covering origins, insertions, actions, and innervations of key muscles discussed in the lecture.

What common action do the hamstring muscles perform at the knee joint?

They flex the knee.

Which hamstring muscle inserts on the fibula?

Biceps femoris.

Where do all three hamstring muscles originate?

The ischial tuberosity of the pelvis.

Which muscle is considered the main plantar flexor for posture?

Soleus.

What two actions does the gastrocnemius muscle perform?

Plantar flexes the foot and flexes the knee.

Which muscle both plantar flexes and inverts the foot?

Tibialis posterior.

Name the muscles that evert and weakly plantar flex the foot.

Fibularis (peroneus) longus and fibularis (peroneus) brevis.

Cranial nerve VII (facial nerve) innervates which group of muscles?

The muscles of facial expression.

Which facial muscle raises the eyebrows and wrinkles the forehead?

Frontalis.

What is the primary action of the orbicularis oculi?

It closes the eyelids.

Which muscle is commonly referred to as the "smile muscle"?

Zygomaticus major (and minor).

What action does the buccinator muscle perform?

It compresses the cheeks during chewing or blowing.

Which muscle flexes the neck when both sides contract and rotates the head when only one side contracts?

Sternocleidomastoid.

Name one muscle that extends and slightly rotates the head.

Semispinalis capitis (also accept Splenius capitis for extension and rotation).

Which abdominal muscle is the deepest layer and compresses abdominal contents?

Transversus abdominis.

Which abdominal muscle creates the visible "six-pack" and flexes the trunk?

Rectus abdominis.

Which muscle elevates, retracts, and depresses the scapula?

Trapezius.

Which muscle is considered the primary elbow flexor?

Brachialis.

Which muscle is responsible for elbow extension?

Triceps brachii.

Which muscle flexes the elbow especially during mid-pronation (e.g., hammer curls)?

Brachioradialis.

What action does the serratus anterior perform on the scapula?

It protracts and stabilizes the scapula.

What is the primary action of the rhomboid major and minor?

They retract (adduct) the scapula.

Which facial muscle closes and purses the lips?

Orbicularis oris.