chapter 11 muscles
joint in the middle sea saw force and load are balanced
first class lever
the joint between the occipital bone of the skull and the first cervical vertebra is part of which class lever system
first class.
general age related effects on skeletal muscles include
decreased skeletal muscle fiber diameters, diminished muscle elasticity, decreased tolerance for exercise, and decreased ability to recover from muscular injuries.
depressor anguli oris
depresses corners of the mouth
depressor labbi inferioris
depresses lower lip
digastric
depresses mandible or elevates larynx
buccinator
moves food around cheeks
the three functional groups tat make up the muscles of the lower limbs
muscles that move the thigh, muscles that move the leg and muscles that move the foot and toes
constricts the mouth opening
ocularis oris
laterial pterygoids
opens jaws, protrudes mandible,or performs lateral excursion
antagonist
opposes prime mover
what muscle surrounds the mouth
orbicularis oris
muscles have one fixed point of attachment called the muscles have one moving point of attachment called the
origin insertion
fibers parallel to long axis of muscle
parallel fibers
examples of convergent muscles
pectoralis muscles, trapezius muscles
correct names of muscles include the names muscle except:
platysma diaphragm
axial muscles
position head and spinal column move rib cage 60% of skeletal muscles
muscles that rotate the radius without prodcuting either flexion or extension of the elbow are the
pronator teres and supinator
origin is usually what to insertion
proximal
corrugator supercilia
pulls the eyebrows down to make a sad expression
frontalis
raises eyebrows wrinkles forehead
a pulled hemstring is what
refers to a strain affecting one or more of the three muscles that collectively flex the knee: the biceps femoris, seimembranosus, and semitendinosus.
splenius capitus
together two sides extend neck, alone each flexes and laterally flexes that neck to the side
proximal
towards an attached base
what muscles move the pectoral girdle
trapezius rhomboidius levator scapulae serratus anterior pectoralis minor
major extensor of the elbow
triceps brachhii
how would a torn calcaneal tendon affect movement of the foot
would make plantar flexion difficult because this tendon attaches the soleus and gastrocnemius muscles to the calcaneus.
what 3 functions are accomplished by the muscles of the pelvic floor
1. suppport the organs of the pelvic cavity flex joints of the sacrum and coccyx and control movment of materials through urethra and anus.
TEMPORALIS
ELEVATES MANDIBLE
prime mover
agonist
second class lever
ankle extension plantar flexion.
the linea alba is a
aponeurosis.
distal
away from an attached base
nuchal
back of neck
example of parallel muscle
biceps brachi
third class lever
biceps brachii
hallucis
big toe
damage to intercostal musces would interfere with
breathing.
fascicles
bundles of muscle cells or fibers
effects of exercise
cardiovascular system: increasing heart rate and dilating blood vessels rate and depth of respiration increases sweat gland secretion increases.
orbicularis oculi
closes eye
compartment syndrome results from
compartments swelling with blood due to an injury involving blood vessels. torn ligaments in a given compartment. pulled tendons in the muscles of a given compartment. f
nasalis
compresses bridge depresses tip of nose elevates corners of nostrils
buccinator
compresses cheeks
orbicularis oris
compresses, purses lips
muscular system
consists only of skeletal muscles
shrugging your shoulders uses which muscles
contracting your levator scapulae muscles.
broad area converges on attachment site muscle fibers pull on different directions
convergent muscles
risorious
draws corners of mouth to the side
mentalis
elevates and protrudes lower lip
mylohoid
elevates floor of hyoid bone or depresses mandible
masseter
elevates mandible and closes the jaw.
scalenes
elevates ribs or flexes neck
medial pterygoid
elevates the mandible and closes the jaw or moves jaw side to side (lateral excursion)
levator labii superioris
elevates upper lip
examples of pennate muscles
extensor digitorum rectus femorus deltoid
pennate muscles
form an angle with the tendon contain more myofibrils and make more tension than parallel muscles
epicranial muscles
frontalis +occipitalis
what major function does the muscular system perofrm for the body as a whole
generates heat that maintains normal body temperature.
inguinal
groin
synergist
help in the movement
a blank develops when an organ protrudes through an abnormal opening
hernia
the powerful flexors of the hip are the
iliopsoas
ilio
ilium
injury of the flexor carpi ulnaris muscle would
impair the ability to perform flexion and adduction at the wrist.
which leg movement would be impaired by injry to the obturator msucle
impair your ability to perform lateral rotation of the hip.
mechanically bones are a what and joints are a what
lever and joints are a fulcrum.
lumboraum
lumbar region
strongest masticatory muscle is the
masseter
the force is in the middle
most common levers in the body greater force moves smaller load maximizes speed in the human body most common muscle used
zygomaticus major
retracts and elevates corner of the mouth
zygomaticus minor
retracts and elevates upper lip
load in middle wheelbarrow is an example small force moves a large weight load between applied force and fulcrum
second class lever standing on tip toes
appendicular muscles
support pectoral and pelvic girdles support limbs 40 % skeletal muscles
muscles involved in a roator cuff injurty are the
supraspinatus, infraspinatus, teres minor, subscapularis
why can swallowing help alleviate the pressure sensations at the eardrum when you are in an airplane that is changing altitude
swallowing invovles contractions of the palatal muscles. elevation of the superior portion of the pharynx enlarges the opening to the auditory tube permitting airflow to the middle ear and the inside of the eardrum.
elongated bursae that reduce friction and surround the tendons that cross the dorsal and ventral surfaces of the wrist form
synovial tendon sheaths
occipital belly
tenses and retracts scalp
platysma
tenses skin of neck depresses mandible
what is fibrosis
the development of increasing amounts of fibrous connective tissue. fibrosis causes muscles to be less flexible and the collagen fibers can restrict movement and circulation.
if you've been lifting things which muscle is most likely sore
the erector spinae muscles especially the longissimus and iliocostalis muscles of the lumbar region.
muscle that rotates the eye medially
the medial rectus
which bones do the four rotator cuff muscles originate and insirt
the supraspinatus infraspinatus and teres minor originate on the posterior body of the scapula, and the subscapularis originate on the anterior body of the scapula. all 4 muscles insert on the humerus.
skeletal muscles are classified by
the way fascicles are organized by relationships of fascicles to tendons
knee extensors known as the quadripcs consist of the
three vastus muscles and the rectus femoris muscle
sternocleidomastoid
together they flex the neck alone one side bends head toward shoulder and turns face to opposite side