Sounds like a school assigment? Shouldn't that be done for you to learn something and think for yourself?
For this assigment, you have to understand the anatomy of the whole Upper body. Including Thoracic Spine, Scapulae, Acromion, Clavicle, The glenoid fossa, coracoideus process, humerus. It's not too easy. The shoulder area and it's movements are one of the most complicated things in human anatomy. There are so many things that you should know.
For joints, there is atleast 6 different joint working. Bones (What an odd question. What bones are used in exercise? huh?) Well, I don't dare to count the many bones and joints on the wrist or hand, so very many. Muscles, God, Very plenty. Atleast 12 or more. Once again, you have to consider the whole upper back. Scapulae are active, shoulders are active, the elbow is active, even the wrist.
I've done this stuff myself. And I must point out that it's very crucial to know atleast the basics of these things. AND actually learning them. The joints and muscles around the shoulders are very injury prone. Plus it would be nice to have a little knowledge about where some muscles come and where they attach. It helps to figure some exercises and it helps to fix the form.
Here's something to get you started:http://exrx.net/WeightExercises/Latissi ... ldown.html