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chapter 10 muscles

rigid bar that moves on a fixed point
fixed point
force is applied to fulcrum
resistance from effort
fusiform muscles
spindle-shaped muscles
has a broad origin and its fascicles converge toward a single tendon of insertion
fascicles are arranged in concentric rings
short and attach obliquely to a central tendon that runs the length of the muscle
mechanical advantage
small effort exerted over a relatively large distance can be used to move a large load over a small distance
mechanical advantage
power lever
mechanical disadvantage
the load is far from the fulcrum and the effort is applied near the fulcrum the force exerted by a muscle must be greater than the load to be moved or supported
mechanical disadvantage
speed lever
first class lever
the effort is applied at one end of the lever and the load is at the other, with the fulcrum somewhere between. (speed and distance)
first class lever
first class lever
raising your head off your chest
second class lever
the effort is applied at one end of the lever and the fulcrum is located at the other, with the load between them (strength)
second class lever
second class lever
third class levers
the effort is applied between the load and the fulcrum
third class levers
third class levers
flexing the forearm to the biceps brachii
third class levers
tend to be thicker and more powerful
the long axes of the fascicles run parallel to the long axis of the muscle
Orgin: cranial aponeruosis IN: skin and muscles around eye and nose
orbicularis oculi
OR: maxillary and frontal bone IN: skin around eye
orbicularis oris
OR: muscles near the mouth IN: skin around the mouth
OR: outer surface of the maxilla and mandible IN: oribicularis oris
OR: zygomatic bone IN: skin and muscles around the mouth
OR: zygomatic arch IN: mandible
OR: temporal bone IN: mandibular coronoid process
OR:sternum and clavicle IN: mastoid process of temporal
OR: occipital bone and all cervical and thoracic vertebra IN: spine of scapula and clavicle
external intercostals
OR: superior rib IN: inferior rib
internal intercostals
OR: inferior rib IN: superior rib
external oblique
OR: lower 8 ribs IN: iliac crest
internal oblique
OR: iliac crest IN: lower 3 ribs
transverse abdominus
OR: lower 6 ribs IN: crest of pubis
rectus abdominus
OR: crest of pubis IN: xiphoid process
rhomboideus major
OR: spines of upper thoracic vertebrae IN: medial border of scapula
OR: posterior surface of scapula IN: greater tubercle of humerus
serratus anterior
OR: upper 9 ribs IN: vertebral border of scapula
OR: accromion process/ spine of scapula/ clavicle IN: deltoid tuberosity of humerus
pectoralis major
OR:clavicle, sternum, 2nd and 6th costal cartilages IN: intertubercular groove of humerus
latissimus dorsi
OR: iliac crest IN: intertubular groove of humerus
teres major
OR: lateral border of scapula IN: intertubular groove of humerus
biceps brachii
OR: scapula IN: radial tuberosity
triceps brachii
OR: scapula, proximal humerus IN: olecrannon process of ulna
OR:anterior humerus IN: coronoid process of ulna
extensor carpi and flexor carpi
OR: humerus IN: carpals and metacarpals
extensor digitorum and flexor digitorum
OR: humerus, radius, ulna IN: phalanges
OR: lumbar vertebra, ilium IN: lesser trochanter of femur
Gluteus maximus
OR: posterior ilium, sacrum IN: proximal femur
Gluteus medius
OR: ilium IN: greater trochanter of femur
adductor group
OR: pubis, ischium IN: femur and tibia
quadriceps femoris
OR: ilium, femur IN: patellar tendon that contiues as a ligament to the tibial tuberosity
hamstring group
OR: ischial tuberosity IN: lateral and medial tibia
OR: ilium IN: medial tibia
OR: condyles of femur IN: calcaneus by way of achilles tendon
tibialis anterior
OR: condyles of tibia IN: tarsal and metatarsal bones
peroneus group
OR: fibula IN: tarsal and metatarsal bones
OR: tibia, fibula IN: calcaneus
Flexor and extensor digitorum longus
OR: tibia, fibula IN: phalanges