Copyright Goodheart-Willcox Co., Inc. Chapter 5 The Skeletal System 165 23. Which of the following is not a function of articular cartilage? A. cushions the joint B. reduces wear to the joint C. reduces friction at the joint D. helps distribute forces evenly 24. Another term for freely movable joints is _____. 25. _____ are small sacs filled with synovial fluid that cushion the structures they separate. 26. _____ connect muscle to bone, while _____ connect bone to bone. 27. Which term describes a fracture in which the ends of a bone protrude from the skin? A. comminuted B. compound C. simple D. avulsion 28. Which type of fracture is more common in children than in adults? A. compound B. avulsion C. greenstick D. simple 29. Injuries to which of the following can stop the growth of a long bone? A. intervertebral disc B. meniscus C. epiphyseal plate D. sutures 30. _____ fractures are tiny, painful cracks in a bone that result from overuse. 31. The site where a tendon attaches to a bone is known as the _____. 32. _____ is an autoimmune disorder in which the body’s own immune system attacks healthy joint tissues. Thinking Critically 33. Given your knowledge of the intervertebral discs, what activities should a person avoid to promote disc health? Name at least two activities and explain why each should be avoided. 34. If a forensic scientist finds skeletal remains after a house fire, how might she determine whether the individual was a male or female? 35. Give reasons why you either would or would not want all of your joints to be ball-and-socket joints. 36. A 10-year-old boy and his 42-year-old father were building a tree house when the branch they were standing on broke away from the tree. The father sustained two broken ribs, but the boy had only a few bruises. What might explain the difference in the severity of their injuries? 37. Why is damage to an epiphyseal plate especially problematic for children? 38. What would happen if osteoclasts in the medullary cavity did not resorb bone while osteoblasts are building new layers of bone inside the periosteum? Why would this be problematic? Clinical Case Study Read again the Clinical Case Study at the beginning of this chapter. Use the information provided in the chapter to answer the following questions. 39. Among the conditions described in this chapter, what do you think might be going on with Dana? 40. Which condition do you think is most likely? Why? Analyzing & Evaluating Data Astronauts who spend an extended amount of time in space may lose 1% to 2% of their bone mass each month if they do not perform regular resistance exercises. 41. If the astronaut spends three months in space and never exercises, what percentage of his bone mass might he lose? 42. You read in this chapter that bones account for about 15% of body weight. If this astronaut weighs 170 pounds, how much do his bones weigh? 43. If he fails to exercise for 6 months in space, how much weight might this astronaut lose in bone mass? Investigating Further 44. Choose one of the following topics: anorexia nervosa, bursitis, dislocation, female athlete triad, fracture, osteoporosis, rheumatoid arthritis, sprain, or stress fracture. Using this textbook as a starting point, research your topic and prepare a report on causes and treatments.