muscles of head and neck and myology Flashcards
function of skeletal muscle
body movement, maintenance of posture, temp regulation, storage and movement of materials, support
what do tendons do?
attach muscle to bone
what do ligaments do?
attach bone to bone
what is aponeuroses?
flattened, thin, sheet like tendons
what kind of tissue are tendons made up of?
dense regular CT
Dense CT and function?
made up of fibroblast cells, has poor vascularity with collagen fibers densely packed and running parallel
Function: strength and support, resists stress in one direction
each skeletal muscle is an organ true or false?
true
what is a muscle fiber wrapped in?
endomysium
what is a group of muscle fibers called?
fascicles
what is a group of fascicles?
the whole muscle
what is the entire muscle surrounded by?
epimysium
what surrounds the CT wrapping?
the deep fascia
what does the deep fascia become eventually?
tendon
what is the superficial fascia?
the subcutaneous layer
what is a myofibril?
groups of myofibrils makes up each muscle fiber, runs full length of a muscle fiber, composed of thick and thin myofilaments
what are myofilaments?
protein filaments within myofibrils, they have fixed length and needs many groups of them to run the length of a fiber, smallest component of a muscle
what is the sarcolemma?
plasma membrane underneath the endomysium
what is the cytoplasm of a muscle?
sarcoplasm
what is the sarcoplasm composed of?
has cell organelles like lysosomes, ribosomes, and endoplasmic reticulum (called sarcoplasmic reticulum)
what does the sarcoplasmic reticulum do?
stores calcium ions and releases ions as needed for muscle contraction
what are the transverse tubules?
each muscle fiber is primarily composed of myofibrils
Function: conducts nerve impulses quickly from sarcolemma though muscle fibers
what are thick myofilaments?
myosin
what are thin myofilaments?
actin
what is the Epicranius?
composed of occipitofrontalis muscle and an epicranial aponeurosis
what does the frontal belly of the occipitofrontalis do?
elevates eyebrows and wrinkles skin of the forehead
What does the occipital belly of occipitofrontalis do?
retracts scalp slightly
what does the orbicularis oculi do?
Closes the eye (Wink)
what does the orbicularis oris do?
closes and purses lips (pucker)
what does the zygomaticus major do?
elevates the corner of mouth for smiling
what does the depressor anguli oris do?
depresses corner of mouth for frowning
what does the buccinator do?
pulls cheeks against teeth when chewing (sucking)
what does the platysma do?
tense skin of neck and depresses lower lip for pouting
what is facial nerve paralysis?
a condition called bell palsy which is paralysis of the muscles of facial expression
what is mastication?
process of chewing, moves the mandible at the temporomandibular joint
what bones are involved in mastication?
mandible, temporal bone, sphenoid bone
what does the masseter do?
elevates and protracts the mandible
what does the temporalis do?
elevates and retracts mandible
what does the medial pterygoid do?
elevates and protracts the mandible, moves it side to side
what does the lateral pterygoid do?
same as medial pterygoid
what does the genioglossus do?
protracts the tongue, sticks the tongue out
what does the styloglossus do?
elevates and retracts tongue, pulls tongue back to mouth
what does the hyoglossus do?
depresses and retracts tongue, pulls it down attached to hyoid
what does the suprahyoid do?
elevates the hyoid, raises the floor of mouth
what does the infrahyoid do?
depresses the hyoid, swallowing and speaking
what does the sternocleidomastoid do?
rotates head to one side, flexes the head and neck, attaches to sternum and clavicle
what does the splenius capitis do?
rotates head to one side, extends head and neck, head bandage
what is congenital muscular torticollis?
shortened sternocleidomastoid, head tilts toward the affected side
