Final answer:
Flexion of the wrist decreases the angle between the forearm and the hand, while extension of the wrist increases it. Flexor and extensor muscles work across the wrist joint to facilitate these movements.
Step-by-step explanation:
Flexion and extension of the wrist are movements that involve changing the angle between the forearm and the hand. Flexion is the bending movement that decreases the angle between the forearm and the hand, bringing the palm closer to the forearm. Conversely, extension is the straightening movement that increases the angle between the forearm and the hand, moving the back of the hand away from the forearm.
muscles such as the flexor digitorum superficialis and flexor digitorum profundus facilitate flexion of the fingers and the hand at the wrist. On the other hand, muscles like the extensor digitorum and extensor carpi radialis brevis are responsible for extending the fingers and aiding in the movement that braces or abducts the hand at the wrist. These forearm muscles attach to the wrist via tendons that are sheathed by fibrous bands known as retinacula, with the flexor retinaculum on the palmar side and the extensor retinaculum on the dorsal side.