41) The only membrane bone that occurs inferior to the skull is the
A) femur.
B) sternum.
C) rib.
D) clavicle.
42) Within a long bone of the skeleton, the circumferential lamellae are located in the
A) trabeculae.
B) osteons.
C) external and internal regions of compact bone.
D) marrow cavity.
43) Muscles are
not
likely to tear from their bones because
A) a circumferential lamella sandwiches the ends of the tendon onto the surface of an adjacent lamella.
B) elastin fibers in the tendon can allow for stretching and recoil of the muscle.
C) perforating fibers of collagen attach the tendons and periosteum to the cortical surfaces of bone.
D) the tendons are partially ossified at their attachment points to the periosteum.
44) The primary center of ossification
A) occurs in the 4-week embryo.
B) is in the diaphysis.
C) is in the epiphysis.
D) is in membrane bones but not in endochondral bones.
45) Osteoblasts probably originate directly from
A) mesenchyme cells.
B) osteoblasts.
C) osteocytes.
D) blood stem cells.
46) A hormone that increases the bone-degrading activity of osteoclasts is
A) an androgen (male sex hormone).
B) an estrogen (female sex hormone).
C) thyroid hormone.
D) parathyroid hormone.
47) Cartilage repairs slowly after adolescence because
A) the perichondrium thickens, preventing diffusion of gasses and nutrients.
B) the cartilage matrix becomes mineralized.
C) chondrocytes no longer are able to divide.
D) collagen synthesis ceases.
48) Which term applies to a number of disorders in adults in which the bones are inadequately mineralized?
A) rickets
B) osteomalacia
C) Paget's disease
D) osteosarcoma
49) Rickets most often results from a deficiency of vitamin
A) A.
B) B.
C) C.
D) D.
50) An osteon is composed of
A) a cell body and a long, threadlike extension.
B) cartilage.
C) layers of bone lamellae surrounding a central canal.
D) interstitial lamellae.