Flashcards in 15CHAPTER 10: MUSCLES Deck (41)
Where is deep fascia found?
found between adjacent muscles
Where would you find superficial fascia (hypodermis)?
adipose between skin and muscles
What are the 2 ways muscle attaches to bone?
Direct and indirect attachment.
What is the difference between direct and indirect attachment?
Direct attachment: epimysium is continuous with periosteum; e.g. intercostals
Indirect attachment: epimysium continues as tendon that merges into periosteum; e.g. biceps brachii
What does muscle attach to other than bone?
The dermis and aponeurosis.
How does muscle attach to the dermis (superficial fascia)?
epimysium attaches to collagen fibers of the dermis e.g. muscles of facial expression
What are aponeurosis?
sheet like tendon; e.g. abdominal muscles
During contraction, bone at one end is stationary (______) and bone at other end moves (_____).
`What does origin mean?
attachment to least mobile bone
What does insertion mean?
attachment to most mobile bone
What is the belly of a muscle?
thicker, middle region of muscle
Strength of a muscle and its direction of action are determined primarily by what?
orientation of its fascicles
What are the 4 types of muscles?
1. Prime mover (agonist)
What is the function of a prime mover and give an example?
Produces most of the force -e.g. brachialis – flexion of the elbow
What is the function of a synergist and give an example?
Aids the prime mover -e.g. biceps brachii refines movement when elbow is flexed
What is the function of an antagonist and give an example?
Opposes the prime mover -e.g. triceps brachii opposes biceps brachii and visa versa (antagonist pair)
What is the function of a fxator and give an example?
Prevents a bone from moving, while a muscle attached to that bone contracts
e.g. fixators (rhomboids) hold scapula in place when biceps brachii contracts
What are intrinsic muscles?
contained within a region – origin and insertion are within the region e.g., the hand
What are extrinsic muscles?
Muscles that act on a region but origins are outside the region e.g., move the fingers but found in the forearm
What is muscle innervation?
Nerve supply to a muscle
What do cranial nerves (arising from the brain) and Spinal nerves (arising from the spinal cord) supply muscles with?
Anterior muscles are what kind of muscles?
Flexors (main exception is the knee)
Posterior muscles are what kind of muscles?
What is the origin and insertion and action of the orbicularis oculi?
O= orbit, I= eyelid, A= closes eye
What is the origin and insertion and action of the orbicularis oris?
O= muscle fibers around mouth, I= Lips, A= closes lips; kissing
What is the origin and insertion and action of the temporalis?
O= parietal bone- temporal lines, I= mandible- coronoid process A= elevates mandible
What is the origin and insertion and action of the masseter?
O= zygomatic arch, I= mandible-angle, A=elevates mandible
What is the origin and insertion and action of the sternocleidomastoid?
O= clavicle, sternum, I= mastoid process of temporal bone, A= flexion of head
What is the origin and insertion and action of the trapezius?
O= nuchal lines of occipital bone, C7-T12, I= clavicle, scapula, A= extension of neck