a, p 6 pt 3

________ hormones stimulate osteoblasts to produce bone matrix. A) Sex B) Growth C) Thyroid D) Parathyroid E) Pancreatic

A) Sex

Elevated levels of calcium ion in the blood stimulate the secretion of the hormone A) calcitonin. B) thyroid hormone. C) parathyroid hormone. D) growth hormone. E) testosterone.

A) calcitonin

Of the total organic components in bone most of it is A) collagen. B) keratin. C) keratohyalin. D) elastin. E) actin.

A) collagen

A ________ fracture shatters the bone. A) comminuted B) greenstick C) compression D) transverse E) spiral

A) comminuted

Calcitonin does all of the following except A) increase bone deposition. B) inhibit osteoclasts. C) cause kidneys to excrete calcium. D) cause less calcitriol to be secreted. E) increase its level in pregnant women.

A) increase bone deposition

Osteoclast-activating factor does all of the following except that it A) is released in large amounts early in life. B) increases the number of osteoclasts. C) increases the activity of osteoclasts. D) produces a severe osteoporosis. E) is released by some cancer tumors.

A) is released in large amounts early in life.

Select the correct words for the following sentence: The (endosteum/periosteum) covers the superficial layer of compact bone and is made up of (the fibrous and cellular layers/osteoblasts, osteoclasts, and osteocytes). A) periosteum; fibrous and cellular layers B) endosteum; fibrous and cellular layers C) periosteum; osteoblasts, osteoclasts, and osteocytes D) endosteum; osteoblasts, osteoclasts, and osteocytes E) endosteum and periosteum; osteoblasts, osteoclasts, and osteocytes

A) periosteum; fibrous and cellular layers

When stress is applied to a bone, A) the minerals in the bone produce a weak electrical field that attracts osteoblasts. B) osteoclast activity increases and osteoblast activity decreases. C) the bone becomes thin and brittle and ultimately fractures. D) the bone compensates by becoming thinner in the region of stress. E) blood supply through the nutrient artery diminishes and thus remodeling proceeds at a much slower rate.

A) the minerals in the bone produce a weak electrical field that attracts osteoblasts

A fracture at the ankle involving both lower leg bones is often called a ________ fracture. A) compression B) Pott's C) displaced D) greenstick E) Colles

B) Pott's

A fracture that affects the malleolus on both lower leg bones is called a ________ fracture. A) carpal B) Pott's C) Colles D) complex E) double-split

B) Pott's

How do sex hormones affect bone growth? A) Testosterone stimulates osteoclast activity. B) They cause ossification to be faster than cartilage replacement. C) They stimulate the cleavage of hydroxyapetite. D) They cause osteoporosis. E) Estrogen causes slower epiphyseal closure.

B) They cause ossification to be faster than cartilage replacement

In normal adult bones, A) there is no turnover of minerals. B) a portion of the protein and mineral content is replaced each year. C) osteoblast activity exceeds osteoclast activity, once bone has been formed. D) osteoclasts continue to be active long after osteoblast activity ceases. E) exercise will have no effect on bone remodeling.

B) a portion of the protein and mineral content is replaced each year

Which hormone increases calcium and phosphate ion absorption by the intestines? A) parathyroid hormone B) calcitriol C) thyroxine D) calcitonin E) estrogen

B) calcitriol

The condition known as osteopenia A) affects mostly women. B) causes a gradual reduction in bone mass. C) is caused by too much vitamin D in the diet. D) is rarely seen as people age. E) only affects the femur.

B) causes a gradual reduction in bone mass.

Where is spongy bone found in long bones? Where is spongy bone found in flat bones? A) diaphysis; between the compact bone layers B) epiphyses; between the compact bone layers C) metaphyses; between the compact bone layers D) between the compact bone layers; medullary cavity

B) epiphyses; between the compact bone layers

After a fracture of the diaphysis has healed, the thickened region that results is called the A) epiphyseal plate. B) external callus. C) dense tuberosity. D) condyle. E) fracture facet.

B) external callus

In a ________ fracture one side of the shaft is split and the other side is bent. A) comminuted B) greenstick C) compression D) transverse E) spiral

B) greenstick

A condition in which bone becomes riddled with holes making them brittle and compromises normal function is called A) osteopenia. B) osteoporosis. C) osteomyelitis. D) osteitis. E) osteomalacia.

B) osteoporosis

Factors that are necessary for proper bone formation include all of the following, except A) vitamin A. B) vitamin E. C) vitamin C. D) the hormone thyroxine. E) vitamin D.

B) vitamin E

Of the total inorganic components in bone, calcium accounts for what percent? A) 17% B) 9.7% C) 39% D) 72% E) 0.72%

C) 39%

Hundreds of years ago, explorers often died of scurvy. How can this bone-related disease be prevented? A) Supplement the diet with more calcium from meat. B) Increase levels of testosterone to stimulate bone repair. C) Supplement the diet with fresh fruit rich in vitamin C. D) Drink more water to promote bone remodeling and repair. E) Amputate fractured limbs to prevent the spread of scurvy.

C) Supplement the diet with fresh fruit rich in vitamin C

If blood calcium levels rise above 11mg/dL which hormone is likely to be activated? A) parathyroid hormone B) estrogen C) calcitonin D) calcitriol E) both calcitriol and parathyroid hormone

C) calcitonin

The fracture of vertebrae subjected to extreme vertical stress is called a ________ fracture. A) comminuted B) greenstick C) compression D) transverse E) spiral

C) compression

Mary is 50 years old and has entered menopause. During a checkup, a bone scan reveals the beginnings of osteoporosis. Her physician suggests hormone therapy. What hormone might she prescribe for Mary? A) thyroid hormone B) growth hormone C) estrogen D) parathyroid hormone E) calcitonin

C) estrogen

Aging has what effect on the skeletal system? A) progressive loss of processes and tuberosities B) fusion of joints, especially in the vertebral column C) loss of calcium and collagen fibers from matrix D) increase in the number of cranial foramina E) increase in adipose tissue in epiphyses

C) loss of calcium and collagen fibers from matrix

If osteoclasts are more active than osteoblasts, bones will become A) denser. B) thicker. C) osteopenic. D) stronger. E) calcified.

C) osteopenic

What gland responds when the blood calcium level is too low? A) thyroid gland B) adrenal gland C) parathyroid gland D) pituitary gland E) hypothalamus

C) parathyroid gland

A lack of exercise could A) cause bones to become thicker. B) cause bones to store more calcium. C) result in porous and weak bones. D) cause bones to become longer. E) cause bones to lose their medullary cavity.

C) result in porous and weak bones.

A(n) ________, or closed, fracture does not break the skin. A) plain B) internal C) simple D) contained E) common

C) simple

How is vitamin D (vitamin D3) related to calcium homeostasis in bone? A) Vitamin D provides a framework for calcium in the matrix. B) Vitamin D is regulated by osteoclast activity. C) Vitamin D is produced by osteoblasts during endochondral ossification. D) Vitamin D is involved in calcium absorption by the digestive tract. E) Vitamin D replaces calcium in the skeleton.

D) Vitamin D is involved in calcium absorption by the digestive tract

A child with rickets often has A) oversized facial bones. B) long fingers. C) frequent bruises. D) bowed legs. E) inadequate muscle development.

D) bowed legs

Bone plays a central role in the regulation of blood levels of A) potassium. B) iron. C) sulfate. D) calcium. E) sodium.

D) calcium

The most abundant mineral in the human body is A) sodium. B) potassium. C) phosphorus. D) calcium. E) hydrogen.

D) calcium

An open or ________ fracture projects through the skin. A) external B) exposed C) complex D) compound E) complicated

D) compound

The hormone calcitonin functions to A) stimulate osteoclast activity. B) decrease the rate of calcium excretion. C) decrease the rate of calcium absorption. D) decrease the level of calcium ion in the blood. E) stimulate osteoblasts and inhibit osteoclasts.

D) decrease the level of calcium ion in the blood.

Excessive growth hormone prior to puberty could result in A) osteoporosis. B) osteopenia. C) rickets. D) gigantism. E) dwarfism.

D) gigantism

While on a school skiing trip in Colorado, Heidi falls and breaks her tibia and fibula in a Pott's fracture. What would you expect as a prominent part of her clinical assessment several hours after the fall? A) hypertension B) tachycardia C) erythema D) hematoma E) cyanosis

D) hematoma

RANKL or receptor activators of nuclear factor kB A) are receptors that bind directly to PTH. B) are found on the surface of osteoclasts. C) are molecules that cause osteoblasts to lay down bone. D) is a signal molecule that stimulates osteoclasts development. E) causes calcium to be excreted by the kidneys.

D) is a signal molecule that stimulates osteoclasts development

A fracture of the bone across its long axis is called a ________ fracture. A) comminuted B) greenstick C) compression D) transverse E) spiral

D) transverse

The disease osteomalacia causes calcium loss from the skeleton, which would result in bones that are A) more resistant to compression. B) stronger and heavier. C) stronger and contain more spongy bone. D) weaker and more flexible. E) weaker and more brittle.

D) weaker and more flexible

What is the correct sequence of steps in bone repair? 1. Cartilage in the external callus is replaced by bone. 2. A hematoma occurs. 3. An internal callus forms at the site of injury. 4. Osteoclasts and osteoblasts remodel the bone at the site of repair. A) 1, 2, 3, 4 B) 2, 1, 3, 4 C) 3, 1, 4, 2 D) 4, 2, 3, 1 E) 2, 3, 1, 4

E) 2, 3, 1, 4

If a tumor secretes high levels of osteoclast-activating factor, which of the following would you expect to occur as a result of this condition? A) increases in blood levels of calcium B) bone fragility C) decreased bone density D) increased osteoclast activity E) All of the answers are correct

E) All of the answers are correct

Mary is 50 years old and has entered menopause. During a checkup, a bone scan reveals the beginnings of osteoporosis. Her physician suggests nutritional therapy. What might she recommend for Mary? A) vitamin C B) vitamin D C) calcium supplements D) dairy products E) All of the answers are correct

E) All of the answers are correct

A transverse fracture of the wrist that may be comminuted is called a ________ fracture. A) Pott's B) Long's C) tarsal D) common E) Colles

E) Colles

Why does osteoporosis affect more women than men? A) Women typically do not get enough calcium in their diet. B) Men do not remodel the skeleton as fast as women. C) Pregnancy causes deossification of bones in women and will lead to osteoporosis. D) Men exercise more than women and therefore have less osteoporosis. E) Women have a decrease in sex hormones after menopause.

E) Women have a decrease in sex hormones after menopause

If blood calcium levels drop below 8.5 mg/dL which hormone is likely to be activated? A) parathyroid hormone B) estrogen C) calcitonin D) calcitriol E) both calcitriol and parathyroid hormone

E) both calcitriol and parathyroid hormone

What are the three ways in which lamellae are organized in compact bone? A) horizontally around an osteon, vertically between osteons, and transversely around the entire bone B) concentrically around an osteon, vertically between osteons, and transversely around the entire bone C) vertically around an osteon, interstitially between osteons, and horizontally around the entire bone D) concentrically around an osteon, vertically between osteons, and parallel around the entire bone E) concentrically around an osteon, interstitially between osteons, and circumferentially around the entire bone

E) concentrically around an osteon, interstitially between osteons, and circumferentially around the entire bone

Damage to a bone because of extreme load, sudden impact, or stresses applied from an unusual direction is called a A) dislocation. B) contortion. C) rupture. D) fragmentation. E) fracture

E) fracture

Parathyroid hormone functions in all of the following ways except A) stimulating osteoclast activity. B) increasing the rate of calcium absorption. C) decreasing the rate of calcium excretion. D) raising the level of calcium ion in the blood. E) inhibiting calcitonin secretion.

E) inhibiting calcitonin secretion

Which three types of bone cells are developmentally related and what is their progression from the earliest to the latest stage? A) osteoclasts to osteoblasts to osteocytes B) osteocytes to osteoblasts to osteoclasts C) osteogenic to osteoclasts to osteoblasts D) osteogenic to osteocytes to osteoblasts E) osteogenic to osteoblasts to osteocytes

E) osteogenic to osteoblasts to osteocytes

The natural age-related loss of bone mass is called A) osteogenesis imperfecta. B) osteoporosis. C) osteomalacia. D) osteodysplasia. E) osteopenia.

E) osteopenia

The ongoing process of tearing down and rebuilding bone matrix is called A) restoration. B) osteolysis. C) resorption. D) ossification. E) remodeling.

E) remodeling.

Where in the body does the production of precursors for the synthesis of calcitriol occur? A) bone B) kidneys C) small intestine D) liver E) skin

E) skin

A ________ fracture is produced by twisting stresses applied to the bone. A) comminuted B) greenstick C) compression D) transverse E) spiral

E) spiral