direction of motions of the parts of the human body

Question 1

usually happens at elbow and knee joints; can happen with all joints

adjacent end of bones may be able to move such that the joint angle between the bones increases (opens) or decreases (closes) in a simple hinge like fashion within a max range of 180 degrees

Answer 1

flexion

Question 2

increase in angle of joint (opening or extending out)

Answer 2

extension

Question 3

results in movement of the arms or legs outward or away from the midlines of the body

Answer 3

abduction

Question 4

reverse motion of abduction, the movement of arms or legs towards the midlines of the body

Answer 4

adduction