lateral rotation
supraspinatus
The rotator cuff muscles are referred to occasionally as the SITS muscles. The Supraspinatus, Infraspinatus, Teres minor and the subscapularis. The Supras. originates on the scapula and inserts on the humerus. The Infras. originates on the scapula and inserts on the humerus(greater tubercle. The Teres minor originates on the scapula and inserts on the humerus. The Subscapularis originates on the scapula and inserts on the humerus(lesser tubercle). The function of this muscle group is to stabilize the shoulder joint. Hope this helps.
The muscle you are referring to is the subscapularis muscle. It originates on the subscapular fossa of the scapula and inserts on the lesser tubercle of the humerus. It is responsible for medial rotation of the shoulder joint.
You have the pectoralis major muscle in the chest wall. It arise from the sternum and the clavicle. It is inserted on the lateral part of the bicipital groove.
olecranon fossa
The depression on the ulna into which the humerus inserts is called the trochlear notch. This forms the hinge joint known as the elbow joint.
The triceps originates on the scapula and proximal humerus and inserts on the olecranon process. The muscles has three heads (hence its name) so it has multiple origins.
on the intertubercular groove of the humerus just lateral to pectoralis major
The biceps brachii muscle.
Pull ups primarily target the muscles in the back and arms, including the latissimus dorsi, biceps, and forearms. While the bones that make up the arms (humerus, radius, ulna) are involved in the movement, the main bones directly involved in pull ups are the scapulae (shoulder blades) and the spine. The scapulae move and stabilize during pull ups, while the spine provides support and alignment throughout the exercise.
Latissimus dorsi
The prime mover for shoulder internal rotation is the subscapularis muscle, which is one of the four muscles that make up the rotator cuff. It originates on the subscapular fossa of the scapula and inserts on the lesser tubercle of the humerus. Contraction of the subscapularis muscle causes internal rotation of the shoulder joint.