Anatomy - which statement is wrong regarding mm? can't figure it out?

I think ALL of these are TRUE. NONE is False. And with regard to the first 2 answers, Caitie and Gian: The rotator cuff muscles DO indeed insert onto tubercles. And the bumps on the humerus are not called tuberosities, although some bumps are (such as on the tibia). The only thing I can think of that could be interpreted as false about c is that the teres minor and infraspinatus muscle might be considered as inserting BELOW the greater tubercle, but really, any book I have seen says ON the greater tubercle, below the insertion of the supraspinatus. I do have a question for you, n bm: if you don't understand the terms used in this question, what have you been studying, and why are you taking this practice test? A person is never going to master such details as the origins and insertions and innervations of muscles unless the use of these various terms is almost second nature . . .

I know which is false, but I have never heard of 'mm' for skeletal muscles. Maybe I've been out of school for too long, but this abbreviation is not familiar to me. However, I do understand the question. Tubercles are not attachments or insertions for muscles of any type. They are nodules or small bumps like you get with a wart, or on the bone with arthritis at the ends of the joints, especially of the fingers. Therefore, rotator cuff muscles do not insert into tubercles. They originate at the scapulae and insert onto the top of the humerus to keep it in the glenoid fossa of the shoulder. The ridges and bumps on bones which provide places for tendon attachments are called processes, not tubercles.

C is correct because all 4 RC (supraspinatus, infraspinatus, subscapularis, teres minor) muscles (mm in this case) insert into either the greater or lesser tubercle of the humerus. A is incorrect if you can even find a single chest muscle that does NOT connect to the ribs - Pectoralis major originates from the sternum aka not ribs B is incorrect because while posterior forearm muscles are mostly supplied by the radian nerve, many of the arm muscles are innervated by the musculocutaneous nerve D is incorrect because nerves work on an "all or none" principle... i.e. a nerve cannot supply ".5 muscle" E is incorrect because the trapezius does not ever cross the shoulder (glenohumeral) joint, it stays on the back Hope this helps! Feel free to contact me with any other questions at GregUx.com :)