Dynamic study Module

Put the steps in endochondral ossification in order from beginning to end of the process. 1.Capillaries and osteoblasts penetrate the cartilage and invade the central region; osteoblasts begin producing spongy bone at the primary center of ossification; bone formation then spreads along the shaft toward both ends of the cartilaginous model. 2.As the cartilage enlarges, chondrocytes near the center of the shaft increase greatly in size, the matrix is reduced to a series of small struts that soon begin to calcify, and the enlarged chondrocytes die and disintegrate, leaving cavities within the cartilage. 3.Capillaries and osteoblasts migrate into the epiphysis, creating secondary ossification centers. 4.Blood vessels grow around the edges of the cartilage, and the cells of the perichondrium convert to osteoblasts. The shaft of the cartilage then becomes ensheathed in a superficial layer of bone. 5.Epiphyses are filled with spongy bone. Articular cartilage remains exposed to the joint cavity; over time it will be reduced to a thin superficial layer. At each metaphysis, an epiphyseal cartilage separates the epiphysis from the diaphysis. 6.Remodeling occurs as growth continues, and osteoclasts erode the central portion, creating a medullary cavity. The bone of the shaft becomes thicker, and the cartilage near each epiphysis is replaced by shafts of bone.

2, 4, 1, 6, 3, 5

Put the steps of intramembranous ossification in the correct order: 1.Entrapment of blood vessels within the bone 2.Differentiation of osteoblasts within the mesenchyme 3.Formation of spongy bone 4.Formation of bony spicules

2,4,1,3,

Which anatomical structures of the skeleton are complex, dynamic organs that contain osseous tissue, other connective tissue, smooth muscle, and neural tissue?

Bones

Which type of lamellae fill in the spaces between the osteons in compact bone? Interstitial lamellae

Interstitial lamellae

Which function of the skeletal system changes the magnitude and direction of the forces generated by skeletal muscles?

Leverage

Which of the following is a function of the skeletal system?

Leverage Support Protection *All of the listed responses *

Which vessels form as blood vessels invade the cartilage model at the start of endochondral ossification?

Nutrient artery and vein

Which vitamins are essential for normal bone growth and remodeling?

Vitamin A & C

Which of the following accurately states a difference between compact bone and spongy bone? a. Spongy bone is arranged into trabeculae. b. Osteons are present in compact bone only. c. Lamellae are present in compact bone only. d. All of the listed responses are correct.

a. Spongy bone is arranged into trabeculae.

Which of the following statements about intramembranous ossification is FALSE? a. It normally occurs in the deeper layers of the dermis. b. It begins when mesenchymal cells differentiate into osteoclasts within the embryonic or fibrous connective tissue. c. Examples of intramembranous ossification include the frontal and parietal bones, the mandible, and the clavicle. d. Intramembranous ossification is also known as dermal ossification.

b. It begins when mesenchymal cells differentiate into osteoclasts within the embryonic or fibrous connective tissue.

Which of the following statements about the skeletal system is FALSE? a. Individual bones or groups of bones provide a framework for the attachment of soft tissues and organs. b. Many bones of the skeleton can change the magnitude and direction of the forces generated by skeletal muscles. c. Calcium is the most abundant mineral in the human body; 98 percent of the calcium in the body is deposited in the bones of the skeleton. d. Red blood cells, white blood cells, and platelets are produced in the yellow marrow, which fills the internal cavities of many bones.

d. Red blood cells, white blood cells, and platelets are produced in the yellow marrow, which fills the internal cavities of many bones.

Which of the following statements regarding factors that regulate bone growth is FALSE? a. Vitamins A and C are essential for normal bone growth and remodeling. b. Normal bone growth requires a constant dietary source of calcium and phosphate salts as well as other ions such as magnesium, citrate, and sodium. c. Hormones regulate the pattern of growth by changing the rates of osteoblast and osteoclast activity. d. The active form of vitamin C, calcitrol, must be obtained from the diet.

d. The active form of vitamin C, calcitrol, must be obtained from the diet.