Axial Muscles - Chapter 11 Flashcards
What are some functions of the axial muscles?
- support head and spinal cord
- facial expression, chewing and swallowing
- aid breathing and protection of abdominal and pelvic organs
What causes changes in facial expression?
contraction of facial expression muscles
Muscles that affect facial expression are located where on the face?
scalp, mouth, nose and eye
What does the occipitofrontalis move?
scalp, eyebrows, and forehead
What does the procerus muscle move?
moves and wrinkles nose
What does the nasalis move?
elevates corners of nostrils
The levator labii superioris causes what movement?
raises the upper lip
The levator angulai oris causes what movement?
draws corners of mouth superiorly and laterally (smile)
What movement does the zygomatic major cause?
elevates corners of mouth
What does the risorius move?
moves corner of lip laterally
What orbicularis oris causse what movement?
compression of lips
The depressor labii inferioris causes the lips the draw in which direction?
laterally
The mentalis causes what movement?
protrudes lower lip and wrinkles chin
The depressor anguli oris causes what movement?
draws corners of mouth inferiorly and laterally (frown)
What does the corrugator supercilii move?
pulls eyebrows inferiorly and medially
What does the orbicularis oculi cause the eyes to do?
closes the eyes
What movement does the buccinator cause?
compresses the cheek
What movement does the platysma cause?
pulls lower lip inferiorly and tenses skin on neck
Most of the muscles of facial expression are innervated by which cranial nerve?
cranial nerve VII
Facial nerve paralysis is caused by
unilateral paralysis of facial muscles
idiopathic paralysis of facial muscles causes what?
Bell palsy
What are the causes of facial nerve paralysis?
- compression of the facial nerve by blood vessel
- exposure to cold temperatures
- herpes simplex I virus
How many extrinsic eye muscles are there?
6
What are the 6 extrinsic eye muscles?
Medial rectus, lateral rectus, inferior rectus, superior rectus, inferior oblique, superior oblique
What does the medial rectus do?
pulls eye medially
what does the lateral rectus do?
pulls eye laterally
what does the inferior rectus do?
pulls eye inferiorly
what does the superior rectus do?
pulls eye superiorly
What does the inferior oblique do?
depresses and turns eye laterally
what does the superior oblique do?
elevates and turns eye laterally
CN III is also known as the
oculomotor nerve
CN IV is also known as the
trochlear nerve
CN VI is also known as the
abducens nerve
What are the muscles involved in mastication?
Temporalis, masseter, lateral pterygoid, and medial pterygoid
Function of temporalis in mastication
elevates and retracts the mandible
function of masseter in mastication
elevates and protracts the mandible
function of the medial pterygoid
protracts and moves the mandible from side to side while chewing
What movements do the intrinsic muscles of the tongue cause the tongue to do?
curl, squeeze, and fold
What are the extrinsic muscles of the tongue?
genioglossus, styloglossus, hypoglossus, patatoglosseus
The genioglossus allows the tongue to
stick out
the styloglossus allows the tongue to
elevate and retract
the hypoglossus allows to tongue to
depress and retract
the palatoglossus allows what movement of the tongue?
posteriorly elevate
The muscles in the pharynx aid in what?
swallowing, by contracting
Most of the muscles in the pharynx are innervated by which cranial nerve?
CN X
What are the primary muscles of the pharynx?
superior constrictor, middle constrictor, and inferior constrictor
What 2 groups are the anterior neck muscles divided into?
suprahyoid and infrahyoid
What do the suprahyoid bones do during swallowing?
elevate the hyoid bone
What do the infrahyoid bones do during swallowing?
depress the hyoid bone
anterolateral muscles flex what?
the head and/or neck
What movements do the posterior muscles do for the head and neck?
extend the head and neck
Which group of muscles are the major muscles of the anterolateral neck muscles?
Sternocleidomastoid muscles
what does bilateral contraction of the Sternocleidomastoid muscles do?
flexion of neck
what does unilateral contraction of the Sternocleidomastoid muscles do?
lateral flexion and rotation of head
what are the major muscles of the posterior neck muscles
splenius capitis, splenius cervicus, semispinalis capitis, and longissimus capitis
What are the 2 major muscle groupings responsible for the movement of vertebral column?
erector spinae muscle group and transversospinalis muscle group
What is the function of the erector spinae muscle group?
maintain posture and help you stand erect
Bilateral contraction of the erector spinae muscle group causes the vertebral column to what?
extend
Unilateral contraction of the erector spinae muscle group causes the vertebral column to what?
flexes laterally
What is the function of the transversospinalis muscle group?
connect and stabilize vertebrae
3 groups of the erector spinae muscles are
iliocostalis, longissimus, and spinalis
What are the muscles of the transversospinalis?
motifides, rotatores, and semispinalis
Function of rotatores
extend and rotate vertebral column
Bilateral contraction of semispinalis results in
extension of vertebral column
Unilateral contraction of semispinalis results in
lateral flexion of vertebral column
What are the muscles involved in inhalation and exhalation?
Diaphragm, external intercostalis, serratus posterior superior, internal intercostalis, serratus posterior inferior, transverse thoracis
Function of the Diaphragm
physically separates the thoracic and abdominopelvic cavities
which muscles elevate ribs during inhalation?
external intercostalis and serratus posterior superior
which muscle depresses ribs during exhalation
serratus posterior inferior and transverse thoacis
muscle that depresses ribs during forced exhalation
internal intercostals
What is the function of the caval opening of the diaphragm?
allow for passage of vena cava
What is the function of the aortic opening (hiatus) of the diaphragm?
location where aorta passes through diaphragm
What is the function of the esophageal opening of the diaphragm?
where esophagus passes through diaphragm
What are the 4 muscles of the abdominal wall?
external oblique, internal oblique, transverse abdominis, abdominis rectus
What are the functions of the 4 anterolateral muscles (abdominal wall)?
compress and hold abdominal organs in place
The 3 layers of muscle of the pelvic floor is known as
pelvic diaphragm
What are the functions of the pelvic diaphragm?
control of defecation, control of urination, and reproductive processes (erection, ejaculation)
What is the perineum?
diamond-shaped region between lower extremities
2 triangles that the perineum is composed of
urogenital ad anal triangle
What does the urogenital triangle contain
external genitalia and urethra
Where is the urogenital triangle located?
anteriorly
What does the anal triangle contain?
the anus
