2) When the triceps brachii muscle contracts, what movements does it produce? When the triceps brachii muscle contracts, it produces extension of the arm.
3) Why is the inferior region of the shoulder joint most vulnerable to dislocation? It is most vulnerable to dislocation because it is the most mobile synovial joint. Because of this it is frail and relies only on the surrounding ligaments, muscles, and tendons for stability.
4) A high school student comes to the emergency room complaining of persistent pain and stiffness in her shoulder joint. In talking with her, you discover that she has been spending many hours trying to improve her pitching skills for her school's softball team. What is likely causing the pain? A shoulder subluxation is most likely causing her pain. This is a partial dislocation of the shoulder and is caused by her overusing her shoulder. This may cause a loose shoulder where her shoulder capsule will be stretched out as well as the ligaments. This could further lead to chronic shoulder instability.
5) Mary wants to enter a weight-lifting competition and consults you as to what type of muscle fibers she needs to develop and how she should go about it. What would you suggest to her? Mary needs to develop her fast muscle fibers. In order to do this, she will need to have frequent, brief and intensive workouts. She also needs to create muscle hypertrophy which will create an enlargement of the stimulated muscle. She can gain this by repeated and exhaustive stimulation which will create more mitochondria. With