Jon's Limb Anatomy Quiz

Explanation
The rotator cuff refers to the group of muscles and tendons that surround the shoulder joint, providing stability and allowing for movement. The joint that is specifically associated with the rotator cuff is the glenohumeral joint, which is the main joint of the shoulder. The other options mentioned in the question, such as the sternoclavicular, acromioclavicular, and humeralclavicular joints, are not directly related to the rotator cuff.

Explanation
Severing the ulnar nerve and the median nerve dorsally in the arm will inhibit cutaneous sensory on the dorsal surfaces of the fingertips. The ulnar nerve innervates the pinky and half of the ring finger, while the median nerve innervates the thumb, index, middle, and half of the ring finger. Therefore, cutting these nerves would result in the loss of sensation in the dorsal surfaces of the fingertips supplied by these nerves. The radial nerve does not innervate the dorsal surfaces of the fingertips, so cutting it would not have an effect on cutaneous sensory in this area.

Explanation
Back/Shoulder, Page 4

Explanation
F: Innervation by the dorsal rami is only includes the skin of the back and the instrinsic back muscles. The brachial plexus provides innervation to other areas. Back/Shoulder; 4.

Explanation
Apical Ectodermal Ridge

Explanation
All but the clavicle, Limb Embryo - 2.

Explanation
Muscle cell precursors are called myoblasts. Myoblasts are immature muscle cells that have the ability to differentiate and fuse together to form mature muscle fibers. They are responsible for the growth and repair of muscle tissue. As myoblasts mature, they lose their ability to divide and fuse to form multinucleated muscle fibers. Therefore, myoblasts play a crucial role in the development and maintenance of muscle tissue.