Final answer:
The musculocutaneous nerve innervates the biceps brachii, brachialis, and coracobrachialis muscles, aiding in forearm flexion, and provides sensory innervation to the lateral forearm through its continuation as the lateral antebrachial cutaneous nerve.
Step-by-step explanation:
The musculocutaneous nerve is a nerve in the upper limb that innervates several muscles and provides sensory input to a specific area of the skin. This nerve primarily innervates the biceps brachii, brachialis, and coracobrachialis muscles, which are involved in flexing the forearm at the elbow. In terms of sensory distribution, the musculocutaneous nerve continues as the lateral antebrachial cutaneous nerve to supply sensation to the lateral aspect of the forearm.