SECTION: THE SKELETAL SYSTEM
1. The axial skeleton includes bones of the skull, spine, ribs, and sternum. All other bones, including those of the arms, legs, shoulders, and hips, make up the appendicular skeleton.
2. Osteocytes are mature bone cells that make up compact bone. Bone marrow is a soft tissue that fills some cavities in spongy bone.
3. Haversian canals are hollow channels in bone tissue. They allow blood vessels to supply nutrients to bone cells.
4. Leukemia is cancer of the tissues that make blood cells.
5. Osteoporosis is caused by the loss of bone tissue as people age.
6. Joints are places where two or more bones meet. Ligaments are strong bands of connective tissue that hold the bones of a movable joint together.
7. Immovable joints permit little or no movement of the bones they join. Slightly movable joints permit a small amount of movement.
8. Bursitis is a disorder that occurs when the fluid-filled sacs that cushion and lubricate joints become swollen. It is common among athletes. Arthritis is a disease that occurs when the cartilage that protects joints is damaged.
9. b
10. d
11. a
12. c
SECTION: THE SKELETAL SYSTEM
1. red bone marrow
2. mostly fat
3. Haversian canals
4. bone marrow
5. spongy bone
6. compact bone
7. periosteum
8. dense connective tissue that forms the hard outer shell of a bone
9. a loosely structured network of separated connective tissue that forms a bone’s porous inner core
10. b
SECTION: THE SKELETAL SYSTEM
1. c 6. c
2. a
3. d
4. e
5. b
7. b
8. a
9. d
10. b