Ch 11 Flashcards
The compact bone that makes up the outer surface of bone is called:
A) cortical.
B) spongy.
C) collagen.
D) trabecular.
A) cortical.
Minerals make up approximately what percentage of bone?
A) 25%
B) 35%
C) 50%
D) 65%
D) 65%
Which organic protein is responsible for the bone matrix that hydroxyapatite binds to?
A) titan
B) collagen
C) hemoglobin
D) trabecular bone
B) collagen
Eighty percent of bone is made up of:
A) spongy bone.
B) collagen.
C) cortical bone.
D) trabecular bone.
C) cortical bone.
When does bone growth and modeling start?
A) during fetal development
B) at birth
C) during infancy
D) during childhood
A) during fetal development
The two-step process in which bone tissue is recycled is called:
A) bone growth.
B) bone modeling.
C) bone remodeling.
D) bone regeneration.
C) bone remodeling.
Bone cells that are responsible for eroding the bone surface during resorption are called:
A) osteoclasts.
B) cortical.
C) osteoblasts.
D) trabecular.
A) osteoclasts.
The tiny mineral crystals that cluster around collagen fibers in bone are called:
A) osteoclasts.
B) hydroxyapatite.
C) trabecular.
D) osteoblasts.
B) hydroxyapatite.
In addition to proper growth and development, bone remodeling is critical in maintaining:
A) blood glucose levels.
B) blood calcium levels.
C) blood coagulation.
D) vitamin D production.
B) blood calcium levels.
At about what age does bone resorption generally begin to occur more rapidly than bone formation?
A) 10
B) 20
C) 40
D) 60
C) 40
Peak bone mass is typically achieved by what age?
A) 2 years
B) puberty
C) 21 years
D) 30 years
D) 30 years
Currently the most accurate assessment tool for measuring bone density is:
A) X-ray.
B) dual energy X-ray absorptiometry.
C) hydrostatic weighing.
D) computed axial tomography.
B) dual energy X-ray absorptiometry.
A T-score between -1 and 1 on a dual energy x-ray absorptiometry (DXA) signifies:
A) lower than normal bone density.
B) osteoporosis.
C) normal bone density.
D) growing bone.
C) normal bone density.
Which of the following T-scores indicates osteoporosis?
A) -3
B) -2
C) 0
D) 2
A) -3
Which is the most abundant mineral in our body?
A) calcium
B) iron
C) phosphorus
D) fluoride
A) calcium
Which of the following is TRUE concerning calcium?
A) Calcium’s alkalinity assists in regulating acid-base balance.
B) Ninety-nine percent of calcium is found in the blood and soft tissue.
C) When blood calcium rises, osteoclasts will liberate calcium from the skeleton.
D) Calcium is a minor mineral.
A) Calcium’s alkalinity assists in regulating acid-base balance.
Which of the following hormones are released when blood calcium levels fall?
A) parathyroid hormone
B) hydroxyapatite
C) calcitonin
D) thyroxin
A) parathyroid hormone
Calcium is primarily absorbed from which area of the intestinal tract?
A) mouth
B) stomach
C) duodenum
D) ileum
C) duodenum
At which of the following stages of the life cycle is calcium absorption the most efficient?
A) pregnancy
B) infancy
C) adulthood
D) later life
B) infancy
Phytates and oxalates can inhibit the absorption of:
A) vitamin E.
B) thiamin.
C) calcium.
D) protein.
C) calcium.
This hormone is secreted by the thyroid gland when blood levels of calcium are too high.
A) calcitonin
B) thyroxin
C) parathyroid hormone
D) T3
A) calcitonin
Assuming equal serving sizes, which of the following foods would be the poorest source of calcium?
A) skim milk
B) whole milk
C) cheddar cheese
D) cottage cheese
D) cottage cheese
Which of the following plant sources of calcium has the lowest bioavailability?
A) kale
B) spinach
C) broccoli
D) Brussels sprouts
B) spinach
Which of the following nutrients is necessary for the absorption of calcium?
A) iron
B) vitamin D
C) zinc
D) phosphorus
B) vitamin D
Which of the following is MOST likely to occur if you were to consume too much calcium via the diet?
A) You would experience hypercalcemia.
B) You would begin to produce kidney stones.
C) Your gastrointestinal tract would limit the absorption of other minerals.
D) Calcium deposits would accumulate in the soft tissues of the body.
C) Your gastrointestinal tract would limit the absorption of other minerals.
Which of the following organs converts the inactive form of vitamin D into the active form the body can use?
A) parathyroid
B) lungs
C) kidneys
D) gallbladder
C) kidneys
Who is at MOST risk for vitamin D deficiency?
A) a young man living near the equator
B) a middle-aged woman living in Alaska
C) a child living in southern California
D) a middle-aged woman living in Florida
B) a middle-aged woman living in Alaska
Which is the primary source of vitamin D in the American diet?
A) seafood
B) chicken
C) green leafy vegetables
D) fortified foods, such as milk
D) fortified foods, such as milk
Vitamin D toxicity is associated with:
A) sunburns.
B) suntan lotions.
C) seafood.
D) supplements.
D) supplements.
One microgram of vitamin D is equivalent to how many International Units (IU)?
A) 10 IU
B) 20 IU
C) 30 IU
D) 40 IU
D) 40 IU
A vitamin D deficiency in adults can lead to:
A) hypocalcemia.
B) rickets.
C) osteomalacia.
D) calcium deposits.
C) osteomalacia.
Individuals who have diseases that result in the malabsorption of ___ are at risk for a vitamin D deficiency.
A) carbohydrate
B) fat
C) minerals
D) protein
B) fat
Insufficient vitamin D during childhood is associated with:
A) rickets.
B) osteomalacia.
C) osteoporosis.
D) hypocalcemia.
A) rickets.
Vitamin K is absorbed from the small intestine and is transported by ____ to the liver.
A) hepatic portal system
B) chylomicrons
C) bile
D) cholesterol
B) chylomicrons
Vitamin K serves as a(n) ___ to various proteins involved in the coagulation of blood and in bone metabolism.
A) inhibitor
B) coenzyme
C) antagonist
D) carrier
B) coenzyme
Newborn infants receive a single injection of vitamin K at birth due to the fact that:
A) newborns do not have enough bacteria in their small intestine to make vitamin K.
B) breast milk is a poor source of vitamin K.
C) the trauma of labor and delivery depletes the newborn’s vitamin K stores.
D) newborns cannot absorb any of the vitamin K from breast milk or formula.
A) newborns do not have enough bacteria in their small intestine to make vitamin K.
A recent meta-analysis of studies evaluating Vitamin K’s role in maintaining bone health has shown that vitamin K:
A) is only involved in bone remodeling.
B) plays no role in bone metabolism.
C) is the primary determinant of bone density.
D) has a modest impact on bone density.
D) has a modest impact on bone density.
The body’s supply of vitamin K comes from dietary sources and is also produced in the:
A) brain.
B) mouth.
C) stomach.
D) large intestine.
D) large intestine.
Formed in our bones, hydroxyapatite crystals are mineral complexes comprised of calcium and:
A) sodium.
B) chloride.
C) phosphorus.
D) vitamin K.
C) phosphorus.
Which of the following foods is high in phosphorus?
A) eggs
B) apples
C) oranges
D) table salt
A) eggs
Most of the body’s phosphorus is stored in:
A) the liver.
B) adipose tissue.
C) the bones.
D) the kidneys.
C) the bones.
Which of the following foods are good sources of magnesium?
A) green, leafy vegetables
B) citrus fruits
C) french fries
D) soft drinks
A) green, leafy vegetables
Which of the following enhances the absorption and retention of dietary magnesium?
A) fiber
B) phytates
C) protein
D) fat
C) protein
One source of magnesium toxicity is:
A) antacids.
B) apples.
C) high meat consumption.
D) soft drinks.
A) antacids.
The majority of our body’s fluoride is stored in the:
A) liver.
B) adipose tissue.
C) teeth and bones.
D) interstitial fluid.
C) teeth and bones.
Fluorosis is associated with:
A) insufficient intake of fluoride.
B) consuming too much fluoride.
C) Alzheimer’s disease.
D) osteoporosis.
B) consuming too much fluoride.
Kyphosis, or dowager’s hump, is a characteristic associated with:
A) fluorosis.
B) osteoporosis.
C) rickets.
D) the female athlete triad.
B) osteoporosis.
What is the primary reason osteoporosis incidence in the United States is expected to increase?
A) inadequate treatment options
B) increased diagnostic tools
C) increased longevity of the population
D) decline in milk consumption
C) increased longevity of the population
Which individual is at the LEAST risk for osteoporosis?
A) thin, elderly male
B) male weight lifter in his 20s
C) petite Asian female
D) thin Caucasian female in her 40s
B) male weight lifter in his 20s
In which phase of the life cycle is bone loss the greatest?
A) puberty
B) pregnancy
C) lactation
D) menopause
D) menopause
Which of the following is a risk factor that increases one’s chances of developing osteoporosis?
A) participation in weight-bearing exercise
B) consumption of a plant-based diet
C) smoking
D) moderate alcohol intake
C) smoking
Mary is 60 years old and at risk for osteoporosis. Which of the following dietary supplements would be the MOST helpful to minimize bone loss, when combined with calcium?
A) magnesium
B) vitamin K
C) phosphorus
D) vitamin D
D) vitamin D
Which group of people do doctors generally advise get a dual energy X-ray absorptiometry (DXA) test?
A) pubescent women
B) postmenopausal women
C) middle-aged men
D) weight lifters
B) postmenopausal women
A T-score compares a person’s assessed bone density to:
A) the average peak bone density of a healthy 30-year-old.
B) the average peak bone density of a healthy 20-year-old.
C) the average bone density of a person with osteoporosis.
D) the average bone density of a person at puberty.
A) the average peak bone density of a healthy 30-year-old.
Dual energy X-ray absorptiometry (DXA) measures bone density in a person’s:
A) lower limbs.
B) hands.
C) hips.
D) whole body.
D) whole body.
The quick, portable procedure that calculates bone density by using sound waves to scan the heel, shin, and kneecap is known as:
A) dual energy X-ray absorptiometry.
B) single energy X-ray absorptiometry.
C) quantitative ultrasound technique.
D) peripheral ultrasound technique.
C) quantitative ultrasound technique.
Which of the following is a hormone that is released in response to low blood calcium levels?
A) serotonin
B) estrogen
C) parathyroid hormone
D) insulin
C) parathyroid hormone
Which of the following foods contains the same amount of calcium as 8 oz of nonfat milk?
A) 4.9 oz plain, nonfat yogurt
B) 4.9 oz Swiss cheese
C) 1.5 oz canned sardines
D) 1 cup of lima beans
A) 4.9 oz plain, nonfat yogurt
Of the following foods, which has the highest bioavailability of calcium?
A) raw spinach
B) unprocessed tofu
C) whole wheat bread
D) cooked kale
D) cooked kale
Which of the following is the animal form of vitamin K, produced by bacteria in the large intestine?
A) osteocalcin
B) menaquinone
C) phylloquinone
D) phosphorus
B) menaquinone
Foods that contain protein have a high amount of:
A) calcium.
B) vitamin K.
C) phosphorus.
D) oxalates.
C) phosphorus.
Which component of teeth increases their resistance to destruction by acids and bacteria?
A) calcium
B) phosphorus
C) hydroxyapatite
D) fluorohydroxyapatite
D) fluorohydroxyapatite
How does fluoride protect against dental caries (cavities)?
A) decreases and reverses tooth demineralization
B) inhibits bone modeling
C) speeds up metabolism of acid-producing bacteria
D) decreases tooth mineralization
A) decreases and reverses tooth demineralization
How can children reduce the risk of fluorosis?
A) Limit ingestion of fluoridated toothpaste.
B) Limit ingestion of fluoridated water.
C) Limit intake of vitamin D supplements.
D) Increase amount of phosphorus from dietary sources.
A) Limit ingestion of fluoridated toothpaste.
Fluoride deficiency has been shown to result in:
A) osteoporosis.
B) dental caries.
C) osteoarthritis.
D) kyphosis.
B) dental caries.
The most effective exercise programs recommended to treat osteoporosis emphasize:
A) stretching.
B) carbohydrate loading.
C) recumbent cycling.
D) weight-bearing activities.
D) weight-bearing activities.
Selective estrogen receptor modulators have been used to treat osteoporosis. They work by:
A) increasing the amount and activity of thyroid hormones.
B) increasing the levels of phosphorus in the blood.
C) promoting an estrogen-like effect on bone tissue.
D) combining estrogen with progestin.
C) promoting an estrogen-like effect on bone tissue.
Which thyroid hormone is used to treat osteoporosis?
A) calcitonin
B) testosterone
C) insulin
D) parathyroid hormone
A) calcitonin
Fluoride is absorbed directly into the teeth and gums.
True
Cortical bone has a faster turnover rate than trabecular bone.
False
Collagen fibers are stronger than steel fibers of the same size.
True
Females reach their full adult height later than males do.
False
The size and shape of bones do not change significantly after puberty.
True
Bone density ceases to increase around 21 years of age in males.
False
Osteoblasts lay down new bone.
True
Dual energy X-ray absorptiometry is an accurate way to evaluate bone density.
True
When dietary intake of calcium is low, calcium absorption increases.
True
Using a sunscreen with SPF 8 or greater can inhibit the synthesis of vitamin D.
True
Vitamin D acts as a hormone.
True
The RDA for vitamin D is based on the assumption that an individual does not get enough sun.
True
Geographical location affects the amount of vitamin D the body is able to synthesize.
True
Skin absorbs vitamin D directly from the sun.
False
Across the life span, vitamin D needs are the lowest for those over the age of 70.
False
Overexposure to the sun can result in vitamin D toxicity.
False
Peripheral dual energy x-ray absorptiometry calculates bone density by scanning all the bones in the body.
False
Some researchers believe excess caffeine consumption can be detrimental to bone health.
True
Phosphorus deficiencies are rare.
True
Most bottled waters do not contain fluoride.
True
As adults age, their bone density declines.
True
Hormone replacement therapy has been proven to be a safe and effective treatment for heart disease.
False
