👉 The arm ion, also known as the upper limb or upper extremity, is a complex anatomical structure composed of bones, muscles, nerves, and tendons that extends from the shoulder to the wrist. It enables a wide range of movements essential for daily activities, such as reaching, grasping, and manipulating objects. The arm ion includes the humerus (upper arm bone), radius and ulna (forearm bones), and various muscles that facilitate flexion, extension, abduction, adduction, and rotation. These muscles are innervated by the brachial plexus, a network of nerves that supply motor function and sensory feedback to the arm. The arm ion is crucial for both fine motor skills, like writing and playing musical instruments, and gross motor functions, such as lifting and throwing. Its intricate design allows for precise control and dexterity, making it vital for human interaction with the environment.
