Final answer:
The major muscles that act on the elbow and forearm include the biceps brachii, brachialis, brachioradialis, triceps brachii, anconeus, pronator teres, pronator quadratus, and supinator.
Step-by-step explanation:
The major muscles that act on the elbow and forearm include the biceps brachii, brachialis, brachioradialis, triceps brachii, anconeus, pronator teres, pronator quadratus, and supinator. The forearm flexors, including the biceps brachii, brachialis, and brachioradialis, flex the forearm. The extensors, such as the triceps brachii and anconeus, extend the forearm. The pronators, including the pronator teres and pronator quadratus, pronate the forearm. Lastly, the supinator turns the forearm anteriorly.