nutrition ch 13

Under normal circumstances, what is the average percentage of dietary iron that is absorbed? a. 10 b. 18 c. 33 d. 60

18

What is the RDA for iron for females 19-50 years old? a. 8 mg b. 10 mg c. 18 mg d. 32 mg

18 mg

In the United States, iron is currently added to which of the following foods? a. Milk and cheese b. Breads and cereals c. Peanut butter and jellies d. Orange juice and tomato juice

Breads and cereals

Which of the following disorders may be linked with the presence of high blood iron? a. Dermatitis b. Diverticulosis c. Heart disease d. Neural tube defects

Heart disease

How does vitamin C enhance iron absorption when consumed in the same meal? a. It activates transferrin b. It keeps iron in the reduced ferrous form c. It releases iron from the proteins in the stomach d. It complexes with iron and promotes mucosal transport

It keeps iron in the reduced ferrous form

When eaten in the same meal, which of the following foods enhances the absorption of iron in legumes? a. Nuts b. Fiber c. Oranges d. Whole-grain breads

Oranges

Which of the following is a characteristic of iron deficiency? a. Blood erythrocyte protoporphyrin levels decline as anemia worsens b. Iron supplements are not as effective at treating anemia as is proper nutrition c. People with anemia generally become fatigued only when they exert themselves d. The concave nails of iron-deficiency anemia result from abnormal ferritin levels

People with anemia generally become fatigued only when they exert themselves

Among the following, which does not contain the MFP factor? a. Tuna b. Spinach c. Hamburger d. Chicken leg

Spinach

Approximately how much iron is lost daily by adults from urine, sweat, and shed skin? a. 1 mg b. 5 mg c. 12 mg d. 18 mg

1 mg

What is the ionic state of ferrous iron? a. -2 b. -1 c. +1 d. +2

+2

What is the ionic state of ferric iron? a. +3 b. +2 c. -2 d. -3

+3

Approximately how many people worldwide are thought to be affected by iron-deficiency anemia? a. 1 million b. 100 million c. 1.6 billion d. 3.5 billion

1.6 billion

What fraction of the total iron content of a normal diet is heme iron? a. 1/100 b. 1/10 c. 1/3 d. 1/2

1/10

If a normal, healthy young adult woman loses an average of 2 mg/day of iron from the body, approximately what minimum amount (mg/day) should she consume from the diet to prevent negative iron balance? a. 2 b. 5 c. 11 d. 19

11

Approximately how much iron would be provided by a balanced diet supplying 2000 kcalories? a. 3 mg b. 6 mg c. 12 mg d. 30 mg

12 mg

Taking into account the efficiency of intestinal absorption of iron, approximately how much dietary iron must be consumed to account for the iron lost by donating a pint of blood? a. 5 mg b. 15 mg c. 50 mg d. 100 mg

15 mg

What is the bioavailability of dietary zinc? a. 2-5% b. 5-10% c. 15-40% d. 50-60%

15-40%

For every 10 adult males with iron deficiency, how many have iron overload? a. 5 b. 10 c. 20 d. 40

20

If a person's body has a total of 5 grams of iron, how many grams would be found in the hemoglobin? a. 1 b. 2 c. 3 d. 4

4

What is the Tolerable Upper Intake Level for iron? a. 45 mg b. 90 mg c. 120 mg d. Twice the RDA

45 mg

What percentage of the iron in a hamburger is nonheme iron? a. 0 b. 20 c. 40 d. 60

60

What percent of the RDA for iron is consumed by the typical woman? a. 33 b. 67 c. 100 d. 130

67

Approximately how much higher is the RDA for iron for a vegetarian woman of childbearing age compared with her nonvegetarian counterpart? a. 33% b. 80% c. 150% d. 200%

80%

Which of the following is a characteristic of iron absorption? a. MPF in plant foods enhances overall iron absorption b. Ferritin in red meat interferes with ferrous iron absorption c. Absorption of heme iron is about 50% higher than nonheme iron d. Transferrin released from pancreatic juice regulates iron uptake from mucosal cells

Absorption of heme iron is about 50% higher than nonheme iron

What is hepcidin? a. A factor in meats that enhances iron absorption b. An intestinal mucosa protein that assists in iron turnover c. A substance in legumes that interferes with iron absorption d. A liver-derived hormone that helps regulate iron absorption and transport

A liver-derived hormone that helps regulate iron absorption and transport

What population group is at the highest risk for iron overload? a. Adult men b. Adult women c. Pregnant women d. Adolescents

Adult men

What is the chief transport substance for zinc in the circulation? a. Albumin b. Metallothionein c. Carbonic anhydrase d. High-density lipoproteins

Albumin

Which of the following describes one aspect of iron toxicity? a. Among men in the United States, it is twice as common as iron-deficiency anemia b. In adults, the consumption of alcohol is somewhat protective against absorption of excess iron c. In most people with this disorder, infections are rare because bacteria are killed by excess iron in the blood d. It is usually caused by a virus that attacks the intestinal mucosal cells leading to unregulated and excessive iron absorption

Among men in the United States, it is twice as common as iron-deficiency anemia

Which of the following would represent a source of possible iron contamination? a. An iron frypan b. An iron chelate c. A ferric iron supplement d. A ferrous iron supplement

An iron frypan

Which of the following characteristics are shared by iron and zinc? a. Neither functions in the maintenance of blood glucose b. Neither is circulated from the pancreas to the intestines and back to the pancreas c. Both are absorbed into intestinal mucosal cells and bound to metallothionein for transport first to the liver d. Both are absorbed into intestinal epithelial cells but may then be lost by normal villus cell renewal processes

Both are absorbed into intestinal epithelial cells but may then be lost by normal villus cell renewal processes

Which of the following is not known to affect iron bioavailability from complete meals? a. Caffeine b. Phytates c. Vitamin C d. MFP factor

Caffeine

Which of the following is descriptive of iron deficiency and behavior? a. The practice of pica may enhance iron absorption b. Changes in behavior precede the appearance of anemia c. The practice of pica may delay the onset of iron-induced behavioral changes d. Adults are more resistant to iron-induced behavioral changes than children

Changes in behavior precede the appearance of anemia

Which of the following is a common side effect from taking iron supplements? a. Itching b. Diarrhea c. Constipation d. Black tongue

Constipation

Which of the following symptoms would ordinarily not be found in individuals with iron-deficiency anemia? a. Fatigue b. Headaches c. Concave nails d. Diminished sense of smell

Diminished sense of smell

Which of the following is the most effective and least costly strategy for preventing an iron deficiency? a. Consume iron supplements at a level 2-3 times the RDA b. Switch to iron cooking utensils and eat 4 servings of red meat daily c. Eat small amounts of citrus products and increase intake of low-fat milk d. Eat small quantities of meat, fish, and poultry frequently together with liberal amounts of vegetables and legumes

Eat small quantities of meat, fish, and poultry frequently together with liberal amounts of vegetables and legumes

Which of the following individuals would most likely not need an iron supplement? a. Two-year-old b. Elderly female c. Pregnant female d. Adolescent female

Elderly female

What is the function of MFP factor? a. Enhances iron absorption b. Acts as an iron enrichment nutrient c. Simulates metallothionein synthesis d. Acts as chelating agent for iron toxicity treatment

Enhances iron absorption

When calculating the amount of iron that can be absorbed from a meal, all of the following factors are of major importance except a. EDTA content. b. phytate content. c. vitamin C content. d. MFP factor content.

EDTA content.

Your cousin Emily is a vegetarian. Since you have just learned in your nutrition class that nonheme iron is absorbed less efficiently than heme iron, you want to make sure Emily is getting enough iron. What should you recommend Emily do to maximize her iron absorption? a. Choose spinach as her main source of iron b. Eat her nonheme iron sources with a glass of milk c. Eat her nonheme iron sources with a glass of orange juice d. Refrain from any major activity after eating to aid digestion/absorption of iron

Eat her nonheme iron sources with a glass of orange juice

Which of the following compounds provides a major storage reservoir for iron? a. Ferritin b. Myoglobin c. Transferrin d. Hemoglobin

Ferritin

What dietary ratio of iron to zinc inhibits zinc absorption? a. 0.5 to 1 b. 1 to 1 c. Less than 2 to 1 d. Greater than 2 to 1

Greater than 2 to 1

What iron-containing compound carries oxygen in the bloodstream? a. Ferritin b. Myoglobin c. Transferrin d. Hemoglobin

Hemoglobin

What is erythrocyte protoporphyrin? a. Iron chelating drug b. Hemoglobin precursor c. Indicator of iron toxicity d. Inherited iron-deficiency disease

Hemoglobin precursor

Which of the following is known as an iron-overload protein? a. Transferrin b. Hemosiderin c. Marrowferritin d. Metallothionein

Hemosiderin

Which of the following represents the order of the stages of iron deficiency? a. Iron stores decline - iron transport diminishes - hemoglobin synthesis falls b. Hemoglobin synthesis falls - iron transport diminishes - iron stores decline c. Iron transport diminishes - hemoglobin synthesis falls - iron stores decline d. Iron transport diminishes - iron stores decline - hemoglobin synthesis falls

Iron stores decline - iron transport diminishes - hemoglobin synthesis falls

Which of the following is found in the first stage of iron deficiency? a. Iron stores decline, as assessed by serum ferritin b. Hemoglobin levels fall, as assessed by complete blood count c. Red blood cell count falls, as assessed by hematocrit count d. Hemoglobin synthesis declines, as assessed by erythrocyte protoporphyrin

Iron stores decline, as assessed by serum ferritin

Which of the following foods should be especially limited in the diet of individuals with hemochromatosis? a. Dairy products b. Fluoridated water c. Iron-fortified cereals d. Carbonated beverages

Iron-fortified cereals

Why are people with iron overload at increased risk for infections? a. Excess tissue iron destroys vitamin C b. Iron-rich blood favors growth of bacteria c. Iron-rich blood impairs the immune system d. Excess tissue iron interferes with antibiotic function

Iron-rich blood favors growth of bacteria

Which of the following is a feature of iron absorption? a. It is lower in people with iron toxicity b. It is higher in people with iron deficiency c. It is lower when iron is in the form of heme rather than non-heme d. It is higher in adults than children due to more mature intestinal function

It is higher in people with iron deficiency

Which of the following is a feature of the disorder hereditary hemochromatosis? a. It is characterized by acrodermatitis b. It is found primarily in women of child-bearing age c. It is associated with defects of copper and zinc absorption d. It is the most common genetic disorder in the United States

It is the most common genetic disorder in the United States

Which of the following population groups is least susceptible to iron-deficiency anemia? a. Older infants b. Children 2-10 years of age c. Women of childbearing age d. Men 20-45 years of age

Men 20-45 years of age

Which of the following is a major binding protein for zinc? a. Ligand b. Ferritin c. Hemosiderin d. Metallothionein

Metallothionein

Which of the following is known to regulate the absorption of zinc? a. Metallothionein in the intestinal cells b. Zinc-releasing enzymes in the intestinal mucosa c. Pancreatic juice containing zinc-absorption enhancers d. Bile acids which form a complex with zinc to promote its absorption

Metallothionein in the intestinal cells

Which of the following defines an association between a protein and a function of zinc? a. Thyroxine: zinc transporter b. Globulin: transports zinc into cells c. Transferrin: essential to zinc excretion d. Metallothionein: promotes zinc homeostasis

Metallothionein: promotes zinc homeostasis

What type of anemia results from iron deficiency? a. Hemolytic b. Megaloblastic c. Microcytic hypochromic d. Macrocytic hyperchromic

Microcytic hypochromic

Which of the following is a characteristic of iron deficiency and behavior? a. Erythrocyte iron levels fall before mental alertness is affected b. Moderate iron deficiency promotes constipation and hyperactivity c. Mild iron deficiency impairs energy metabolism and neurotransmitter synthesis d. Iron deficiency increases risk for infections that promote dysfunctional behavior

Mild iron deficiency impairs energy metabolism and neurotransmitter synthesis

Which of the following is a feature of iron nutrition? a. Iron plays an important role in the synthesis of thyroxine b. On average, people absorb about 50-60% of dietary iron c. On average, women do not eat enough iron-containing foods d. Iron deficiency represents the second most common mineral deficiency in the United States

On average, women do not eat enough iron-containing foods

What is the chief function of hemosiderin? a. Stores excess body iron b. Inhibits hemoglobin synthesis c. Enhances heme iron absorption d. Enhances nonheme iron absorption

Stores excess body iron

Which of the following is a feature of zinc in nutrition? a. Pancreatic enzymes are rich in zinc b. The body's primary excretory route is urine c. Good food sources are whole-grain products d. Toxicity symptoms include constipation and low body temperature

Pancreatic enzymes are rich in zinc

What is the name given to the ingestion of nonnutritive substances? a. Pica b. Goiter c. Tetany d. Hemosiderosis

Pica

Which of the following foods provides the greatest amount of iron per serving? a. Yogurt b. Skim milk c. Pinto beans d. American cheese

Pinto beans

What is the major cause of iron deficiency? a. Blood loss b. Poor nutrition c. Hereditary defect d. Parasitic infections of the GI tract

Poor nutrition

Which of the following characteristics is shared by zinc and iron? a. Good food sources include dairy products b. Proteins in the blood are needed for their transport c. Severe deficiencies lead to delay in the onset of puberty d. Doses of 10 times the RDA may cause death in children

Proteins in the blood are needed for their transport

A person with high blood levels of hepcidin responds by a. decreasing iron absorption. b. increasing iron absorption. c. decreasing zinc absorption. d. increasing zinc absorption.

decreasing iron absorption.

Iron overload is also known as a. ferrocyanosis. b. hemoglobinemia. c. hemochromatosis. d. metalloferrothionosis.

hemochromatosis.

Common terms that describe the body's accumulation of excess iron include all of the following except a. iron overload. b. hemosiderosis. c. hemoglobinemia. d. hemochromatosis.

hemoglobinemia.

Which of the following has been shown to improve absorption of iron from iron supplements? a. Taking then with milk b. Taking them with orange juice c. Taking them on an empty stomach rather than with meals d. Taking them in the form of the ferric salt rather than the ferrous salt

Taking them on an empty stomach rather than with meals

Which of the following is a characteristic of the trace minerals? a. A deficiency sign common to many trace minerals is dermatitis b. The amounts in foods are dependent, in part, on soil composition c. Deficiencies are more difficult to recognize in children than in adults d. The amount of all trace minerals in the average person totals approximately 100 grams

The amounts in foods are dependent, in part, on soil composition

A measure of the amount at which a nutrient is absorbed and used by the body is termed a. net utilization. b. bioavailability. c. biological value. d. utilization efficiency.

bioavailability

Signs of iron toxicity include all of the following except a. apathy. b. fatigue. c. hypochromic anemia. d. increases in infections.

hypochromic anemia.

Which of the following is a protein that carries iron through the circulation to the tissues? a. Albumin b. Transferrin c. Hemosiderin d. Metallothionein

Transferrin

Which of the following is a characteristic of iron transport? a. Albumin is the major iron transport protein in the blood b. Transferrin in the blood carries iron to the bone marrow c. Hemochromatosis results from inability to absorb and transport iron d. Ferritin functions by transporting iron from the spleen to the bone marrow

Transferrin in the blood carries iron to the bone marrow

Which of the following is a common example of iron contamination in the diet? a. Using an iron skillet to scramble eggs can triple their iron content b. Cooking acidic foods in a copper pot can extract chelate iron from the pot c. Simmering acidic foods in glass dishes leads to leaching of iron salts from the glass d. Cooking leafy vegetables in a galvanized pot leads to a six-fold increase in iron content

Using an iron skillet to scramble eggs can triple their iron content

Which of the following nutrients enhances iron absorption from the intestinal tract? a. Biotin b. Calcium c. Vitamin D d. Vitamin C

Vitamin C

Which of the following minerals undergoes enteropancreatic circulation during normal metabolism? a. Iron b. Zinc c. Copper d. Fluoride

Zinc

The most common cause of iron overload is a. an injury to the GI tract. b. a genetic predisposition. c. excessive use of iron cookware. d. excessive use of iron supplements.

a genetic predisposition.

All of the following factors are known to enhance the absorption of iron except a. MFP factor. b. organic acids. c. ascorbic acid. d. calcium from milk.

calcium from milk.

Low levels of blood hemoglobin most likely indicate a deficiency of a. zinc. b. iron. c. copper. d. manganese.

iron.

The erythrocyte protoporphyrin level is used as an indicator of a. late iron toxicity. b. early iron toxicity. c. late iron deficiency. d. early iron deficiency.

late iron deficiency.

Absorption of iron from supplements is improved by taking them with a. tea. b. meat. c. milk. d. whole-grain bread.

meat.

An enzyme in which zinc or copper is an integral part of its structure is classified as a(n) a. metalloenzyme. b. oxidoreductase. c. cytochromidase. d. metallothionase.

metalloenzyme.

All of the following are body proteins directly involved in iron metabolism except a. ferritin. b. transferrin. c. hemosiderin. d. metallothionein.

metallothionein.

All of the following are chief storage sites for surplus iron except the a. liver. b. spleen. c. muscle. d. bone marrow.

muscle.

Zinc is known to play an important role in all of the following functions except a. wound healing. b. synthesis of retinal. c. production of sperm. d. oxidation of polyunsaturated fatty acids.

oxidation of polyunsaturated fatty acids.

A child diagnosed with iron-deficiency anemia would most likely benefit from increasing the consumption of a. milk. b. red meat. c. fresh fruits. d. yellow vegetables.

red meat.

All of the following are known to reduce the absorption of iron except a. tea. b. coffee. c. sugars. d. phytates.

sugars.

All of the following characteristics are shared by iron and zinc except a. absorption is inhibited by fiber. b. absorption is inhibited by cow's milk. c. transport in the blood is primarily by albumin. d. absorption rises with increased needs of the body.

transport in the blood is primarily by albumin.

Which of the following foods provides iron in the most absorbable form? a. Rice b. Spinach c. Chicken d. Orange juice

Chicken

The most common tests to diagnose iron deficiency include all of the following measures except a. size of red blood cells. b. number of red blood cells. c. DNA content of red blood cells. d. hemoglobin content of red blood cells.

DNA content of red blood cells.

Which of the following is known to enhance iron absorption? a. Tea b. Coffee c. Foods containing vitamin C d. Foods containing vitamin E

Foods containing vitamin C

What is the average lifespan of red blood cells? a. Two weeks b. One month c. Four months d. Six months

Four months

All of the following are known to reduce the absorption of iron except a. phytates. b. MFP factor. c. soybean protein. d. tannic acid in tea.

MFP factor.

How would the body typically respond to loss of blood from hemorrhage? a. More transferrin is produced to allow absorption and transport of more iron b. The average life of the red blood cell is increased in order to allow better tissue oxygenation c. Fewer iron storage proteins are produced, which increases the amount of iron available for synthesis of new red blood cells d. The liver and muscles release their supply of stored red blood cells, which compensates, in part, for the decrease in red blood cell concentration of the circulation

More transferrin is produced to allow absorption and transport of more iron

Which of the following is a characteristic of iron utilization? a. Most of the body's iron is recycled b. The chief storage site for iron is the intestinal epithelium c. Iron is absorbed better from supplements than from foods d. Iron from nonheme food sources is absorbed better than that from heme food sources

Most of the body's iron is recycled

What is the oxygen-carrying protein of muscle cells? a. Transferrin b. Myoglobin c. Hemoglobin d. Cytochrome

Myoglobin

About how much iron is absorbed from a vegetarian diet compared with an omnivorous diet? a. The same b. One-half as much c. Twice as much d. Three times as much

One-half as much

Why is taking vitamin C ineffective at enhancing iron absorption from standard iron supplements? a. The iron in the supplement is in a chelated form b. The iron in the supplement is already in the ferrous form c. The iron in the supplement binds irreversibly with vitamin C d. The iron supplement already contains MFP to enhance absorption

The iron in the supplement is already in the ferrous form

Why are hemoglobin and hematocrit tests of limited usefulness in the assessment of iron status? a. They are expensive to perform b. They are notoriously inaccurate c. They are late indicators of iron deficiency d. The range of normal value is usually wide

They are late indicators of iron deficiency

Which of the following is not a general feature of the trace minerals? a. Mild deficiencies are easy to overlook b. They are rarely found in dietary supplements c. Most are toxic at only 2½-7 times the requirements d. The amounts contained in supplements are free from regulation by the FDA

They are rarely found in dietary supplements

Iron deficiency in children is likely to result from a diet that overemphasizes a. milk. b. cereals. c. vegetables. d. dried beans.

milk.