Final answer:
The flexor carpi ulnaris muscle flexes and adducts the hand at the wrist, while the extensor carpi ulnaris muscle extends and adducts the hand, involving movements important for various hand positions necessary for everyday tasks.
Step-by-step explanation:
These two muscles in the forearm are responsible for different actions when it comes to hand and wrist movement. The flexor carpi ulnaris muscle works to flex and adduct the hand at the wrist, essentially bringing the hand closer to the forearm while also moving it towards the little finger side. The extensor carpi ulnaris muscle, on the other hand, is responsible for extending and adducting the hand. This means it increases the angle between the hand and forearm while also drawing the hand towards the pinky side. Together, these muscles are involved in movements that allow for various hand positions, which are essential for completing many everyday tasks.