anatomy · section one
the skeleton
206 bones · 237 joints
Point at the drawing, or search for a bone by any name you know it by. Choosing one marks it in ink and turns everything it joins onto green, because a bone on its own tells you almost nothing — what it does is decided by what it is attached to.
green marks what it joins onto
“humerus. two of them.”
appendicular skeleton · arm
Humerus
Humerus · two of them · also called upper arm bone
It carries the weight of the whole arm and gives the muscles that bend and straighten the elbow something solid to pull against. Squeeze your upper arm past the biceps to the hard rod underneath, then follow it up to the ball at the shoulder and down to the two knobs either side of your elbow.
the funny bone is not a bone - it is a nerve you can press against the knob on the inner side of this one
what it joins onto
- glenohumeral jointsynovial ball-and-socketball in socket - swings the arm in any direction
- humeroradial jointsynovial ball-and-socketbends the elbow and lets the forearm twist
- humeroulnar jointsynovial hingehinge - bends and straightens the elbow
62 entries, 206 bones