Module 3 (Muscles of the Axial Skeleton) Flashcards
What does contraction of facial muscles cause
Various facial expressions by moving the skin
What are the facial muscles
Frontalis
Orbicularis oculi
Zygomaticus
Orbicularis oris
Where is the frontalis found and what does it do
Covers the frontal bone and lifts the eyebrow, causing the forehead to wrinkle
Where is the orbicularis oculi found and what does it do
Surrounds the eye and originates on the frontal and maxillary bones
Forcefully closes the eye when contracted
Where is the zygomaticus found and what does it do
Extends from the zygomatic arch to the corners of the mouth
Draws the angle of the mouth superiorly and posteriorly, causing smiling
Where is the orbicularis oris found and what does it do
Originates on the maxillary bone and mandible
Surrounds the mouth and enables the puckering of lips
Which 2 muscles causing chewing
Temporalis and masseter
Where is the temporalis found and what does it do
Fan-shaped muscle that extends from the temporal fossa of the parietal bone to the coronoid process of the mandible
Elevates and pulls the mandible posteriorly (retract)
Where is the masseter found and what does it do
Extends from the zygomatic arch to the angle of the mandible
Elevates and moves the jaw anteriorly (protract)
What are the muscles that move the head (neck muscles)
Sternocleidomastoid
Semispinalis capitis
Splenius capitis
What does the sternocleidomastoid do
Flexes the neck with bilateral contraction and rotates the head to the opposite side with unilateral contraction
What does the semispinalis capitis do
Extends the neck with bilateral contraction and slightly turns the face to the opposite side with unilateral contraction
What does the splenius capitis do
Extends the neck with bilateral contraction and causes flexion and lateral rotation of the neck with unilateral contraction
What do intercostal muscles do
External (inhalation) and internal (expiration) intercostal muscles aid in breathing
What is the muscle of the back and what does it do
Erector spinae
Runs down both sides of the spinal column and keeps the spine erect
What are the muscles of the abdomen
External obliques
Internal obliques
Transversus abdominus
Rectus abdominus
External obliques
Most superficial
Fibres run anteriorly and inferiorly
Functions of external obliques
Bilateral - flexes the vertebral column and compresses the abdominal wall, used in forced expiration
Unilateral - lateral flexion and rotation of the vertebral column
Internal obliques
Lies deep to external obliques
Fibres run anteriorly and superiorly
Functions of internal obliques
Bilateral - flexes the vertebral column and compresses the abdominal wall
Unilateral - lateral flexion and rotation of the vertebral column
Transversus abdominis
Lies deep to the internal obliques
Fibres run horizontally
Functions of transversus abdominus
Bilateral - flexes the vertebral column and compresses the abdominal wall, used in forced expiration
Unilateral - lateral flexion of the vertebral column
What is the linea alba
Line of connective tissue down the middle of the abdomen for muscle attachment
What is the rectus abdominis and what separates it
Lies on either side of the linea alba
Separated by tendinous intersections
Functions of the rectus abdominis
Flexion of the trunk
Forced expiration
