Question

The proximal end of the ulna illustrates the relationship of form and function. the rounded trochlear notch articulates with the hourglass shape of the trochlea. this forms a joint that allows for ________. the hinge like motion of the forearm the rotational motion of the forearm the curling of the fingers the hyper extension of the forearm

Answer 1

Option A, The hinge like motion of the forearm

Step-by-step explanation:

A hinge joint allows for two motions at a time

a) Flexion - The bending motion

b) Extension - The strengthening motion of arm bones

At the proximal end , the Ulna forms a joint with the humerus and radius of forearm. The Ulna extends to form olecranon (the tip of the elbow) Both Ulna and radius bones are attached with an interosseous membrane that causes movement just like a hinge joint.

Option A is correct

Answer 2

I believe that this forms a joint that allows for hinge like motion of the forearm.
The ulna extends through the forearm from the elbow to the wrist, narrowing significantly towards its distal end. At the proximal ends it forms the elbow joint with the humerus of the upper arm and the radius of the forearm. The ulna then extends past the humerus to form the tip of the elbow (olecranon). The hinge like motion of the elbow joint places the point of the olecranon well under the middle of the upper arm.