Advertisement Upgrade to remove ads


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

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording