Nutrition - Exam 3 Study Guide

The dish that has the best potential to reverse night blindness is: - ½ cup brown rice. - 1 cup whole milk. - 3-ounce serving of chicken liver with onions. - ½ cup cooked carrots.

- 3-ounce serving of chicken liver with onions.

For adults age 19 to 50, the RDA for vitamin D is: - 400 IU. - 600 IU. - 900 IU. - 1000 IU. - 4000 IU.

- 600 IU.

Which of the following is NOT true regarding the absorption of fat-soluble vitamins? - Bile is necessary. - Fat-soluble vitamins are incorporated into chylomicrons and transported into the lymph. - Absorption occurs in the small intestine. - A low-fat meal has no effect on fat-soluble vitamin absorption.

- A low-fat meal has no effect on fat-soluble vitamin absorption.

Which statement about coenzymes is FALSE? - All B vitamins function as coenzymes. - A coenzyme attaches to the enzyme to form an active complex. - Some enzymes require a coenzyme to carry out their function or activity. - Coenzymes are a part of the enzyme structure.

- Coenzymes are a part of the enzyme structure.

Why are coenzymes necessary for chemical reactions? - Coenzymes are considered part of the enzyme structure. - Coenzymes directly catalyze reactions when an enzyme is not available. - Coenzymes are responsible for carrying substrates to the active site of an enzyme. - Coenzymes are necessary to activate enzymes, speeding up reaction time.

- Coenzymes are necessary to activate enzymes, speeding up reaction time.

Macrocytic (megaloblastic) cells are formed when: - the oxygen-carrying capacity of megaloblastic cells is impaired, so the red blood cells adjust by getting bigger. - red blood cell precursors combine to form larger-than-normal cells. - DNA synthesis is uninhibited, leading to larger-than-normal cells. - DNA synthesis is impaired, and the red blood cell precursors don't fully divide.

- DNA synthesis is impaired, and the red blood cell precursors don't fully divide.

Which statement about free radicals is NOT true? - Free radicals generated by energy metabolism are not useful to the body. - Free radicals are molecules with unpaired electrons, making them highly reactive. - High levels of free radicals alter DNA and destabilize membranes. - Free radicals arise from exposure to UV radiation, cigarette smoking, and air pollution.

- Free radicals generated by energy metabolism are not useful to the body.

All but one of the following statements are true: - Symptoms of megaloblastic anemia include fatigue, pale skin, and muscle weakness. - Megaloblastic anemia occurs with either a folate or a B12 deficiency, disrupting DNA synthesis. - Impaired DNA synthesis arrests cell division, blocking the full maturation of red blood cells. - Megaloblastic anemia is characterized by abnormally large immature red blood cells with no nuclei.

- Megaloblastic anemia is characterized by abnormally large immature red blood cells with no nuclei.

When blood calcium levels are low, which of the following will NOT occur? - Parathyroid hormone increases calcium release from bone. - Calcitriol increases calcium uptake from urine. - Calcitriol increases absorption of calcium from the intestines. - Parathyroid hormone stimulates the kidneys to increase production of calcitriol.

- Parathyroid hormone increases calcium release from bone.

Which of the following is NOT true of vitamin C? - A deficiency can cause blood vessels to leak. - It functions as an antioxidant. - Regular supplements do not alter the duration of a cold. - Chili peppers are an outstanding source of the vitamin.

- Regular supplements do not alter the duration of a cold.

Which statement regarding the conversion of provitamin A is true? - Beta-carotene is converted to retinol. - Retinal is irreversibly converted to retinoic acid. - Retinal can be converted into beta-carotene. - Retinal and retinol cannot be readily interconverted.

- Retinal is irreversibly converted to retinoic acid.

Which statement correctly matches the retinoid with its description? - Retinal is the storage form of vitamin A. - Retinoic acid regulates hormonal function and DNA expression. - Retinoic acid is added to low-fat and fat-free dairy products in the United States. - Retinol plays an important role in vision.

- Retinoic acid regulates hormonal function and DNA expression.

Which step comes first in a chemical reaction catalyzed by a coenzyme? - The enzyme is activated. - The products are released. - The chemical reaction takes place. - The substrate binds to the enzyme.

- The enzyme is activated.

Which of the following is true for ALL B vitamins? - They all play critical roles in energy metabolism. - They all function as coenzymes. - They are readily destroyed during food storage and cooking. - They cannot be synthesized in the human body.

- They all function as coenzymes.

Which of the following is NOT a function of vitamins? - They perform regulatory functions in the body. - They are critical structural components of cells. - They are needed for proper cell growth. - They are used in metabolism to extract energy from macronutrients.

- They are critical structural components of cells.

Which of the following is a true statement regarding nutrient bioavailability? - Folate must be bound to intrinsic factor to be absorbed. - Low levels of gastric acid production will reduce the absorption of vitamin B6. - Vitamin C improves the bioavailability of iron. - Niacin equivalents adjust for differences in bioavailability between forms of niacin.

- Vitamin C improves the bioavailability of iron.

Which is NOT true regarding vitamin E's role as an antioxidant? - Vitamin E can prevent oxidative changes in LDL cholesterol and thus reduce plaque formation in blood vessels. - Vitamin E protects cell membranes from free radical damage by donating an electron to the free radicals without becoming unstable itself. - Vitamin E does not protect white blood cells from oxidative damage. - Because vitamin E is fat-soluble, it is incorporated into cell membranes.

- Vitamin E does not protect white blood cells from oxidative damage.

Which statement is NOT true regarding vitamin A's role in vision? - When rhodopsin absorbs light, retinal is released from rhodopsin forming opsin. - Rhodopsin is a pigment made up of opsin and retinal. - Vitamin A deficiency delays reformation of rhodopsin, resulting in night blindness. - When light strikes rhodopsin, retinal changes its shape from trans to cis.

- When light strikes rhodopsin, retinal changes its shape from trans to cis.

Which food provides the greatest amount of vitamin E? - spinach (1 cup) - hard-boiled egg - almonds (2 ounces) - olive oil (1 tbsp) - blackberries (1/2 cup)

- almonds (2 ounces)

Beta-carotene is called provitamin A, meaning it is: - stored as is by the liver. - an inactive, precursor form of vitamin A. - the synthetic form of vitamin A, used to fortify foods and supplements. - more bioavailable than preformed vitamin A.

- an inactive, precursor form of vitamin A.

Which is NOT a function of vitamin D? - blood calcium regulation - bone growth and maintenance - immunity - antioxidant - cell development

- antioxidant

Which is not a fat-soluble vitamin? - tocopherol - vitamin D - ascorbic acid - retinoic acid - vitamin K

- ascorbic acid

The snack that would provide good sources of folate and vitamin B12 for Megan, who has megaloblastic anemia, is: - an apple, string cheese, and a glass of cranberry juice. - white corn tortilla chips with salsa. - beef jerky and a pear. - avocado on toast, orange slices, and a glass of fortified soy milk.

- avocado on toast, orange slices, and a glass of fortified soy milk.

Which vitamin functions as a hormone? - vitamin A - vitamin D - vitamin K - both vitamins K and E - both vitamins A and D

- both vitamins A and D

Which foods are the richest source of beta-carotene? - beef liver and tuna - skim milk and other low-fat dairy products - dark, leafy, green vegetables - carrots and sweet potatoes - mango and pink grapefruit

- carrots and sweet potatoes

Excess of which nutrient can cause toxic effects of excess perspiration and fishy body odor? - thiamin - vitamin C - niacin - vitamin B6 - choline

- choline

Rhodopsin is formed when: - cis-retinal is converted to rhodopsin when light hits the rod cell. - cis-retinal combines with opsin. - beta-carotene is converted to rhodopsin. - trans-retinal combines with opsin.

- cis-retinal combines with opsin.

Retinol is an important source of preformed vitamin A in the United States, found in foods such as: - carrots and other orange fruit and vegetables. - dark, leafy green vegetables. - dairy products that contain fat. - nuts and seeds.

- dairy products that contain fat.

Which of the following is NOT a typical cause of a vitamin deficiency? - increased vitamin losses - increased vitamin requirements - decreased vitamin synthesis - decreased vitamin absorption

- decreased vitamin synthesis

Which must be present for fat-soluble vitamins to be absorbed? - calcium and intrinsic factor - calcium and LDL - dietary lipids and bile - dietary lipids and LDL - dietary lipids and insulin

- dietary lipids and bile

Which foods provide the richest source of riboflavin? - eggs, dairy, nuts, and fish - olive, sunflower, and canola oils - oranges and apples - lentils and pinto beans - leafy greens

- eggs, dairy, nuts, and fish

Excess intake of what vitamin can mask the early signs of a vitamin B12 deficiency and lead to cognitive impairment? - folate - vitamin B6 - niacin - thiamin

- folate

The bioavailability of which two vitamins is significantly higher in supplemental form as compared to what is naturally occurring in foods? - niacin and riboflavin - folate and vitamin B12 - thiamin and vitamin B6 - biotin and pantothenic acid

- folate and vitamin B12

Megaloblastic anemia is caused by deficiency in either: - thiamin or vitamin B12. - folate or iron. - thiamin or vitamin B6. - folate or vitamin B12.

- folate or vitamin B12.

Which of the following INCORRECTLY matches the vitamin with a consequence or concern related to a deficiency of that vitamin? - thiamin—Those who abuse alcohol are at particularly high risk of a deficiency. - folate—A deficiency impairs hemoglobin synthesis. - vitamin B12—The risk of deficiency is increased in the elderly. - folate—A deficiency during pregnancy increases the risk of neural tube defects in the infant.

- folate—A deficiency impairs hemoglobin synthesis.

The following choices pair a vitamin with one of its highest natural food sources. Which choice is incorrect? - thiamin—pork - vitamin B6—chicken breast - vitamin C—kiwi - folate—fish

- folate—fish

Which foods provide the richest source of folic acid? - eggs and dairy - fish and shellfish - fortified cereals - spinach and broccoli - citrus fruits and bell peppers

- fortified cereals

The impact of megaloblastic anemia is that: - large red blood cells remain in the bone marrow and don't circulate in the bloodstream. - immature red blood cells become nonfunctional and are eventually degraded. - immature red blood cells have decreased oxygen-carrying capacity. - large white blood cells reduce immune response.

- immature red blood cells have decreased oxygen-carrying capacity.

When low calcium levels are detected in the blood, the parathyroid hormone triggers the kidneys to increase calcitriol production and: - increase the concentration of urine. - increase calcium uptake from the urine. - move calcium into the bones. - prioritize calcium for use by the heart muscle.

- increase calcium uptake from the urine.

Which deficiency condition is related to vitamin A's role in maintaining epithelial tissue? - hypervitaminosis A - osteomalacia - reduced immune function - keratinization - skin cancer

- keratinization

To maintain calcium levels in the bloodstream, active vitamin D, or calcitriol, works with the _____, the _____, and the _____. - skin; intestine; liver - kidney; bone; intestine - liver; kidney; bone - kidney; liver; skin

- kidney; bone; intestine

For the body to use inactive vitamin D from sunlight or the diet, the _____ and then the _____ convert it to its active form. - liver; parathyroid gland - parathyroid gland; kidneys - liver; kidneys - kidneys; liver

- liver; kidneys

Vitamin A deficiency in developing countries is related to: - low intake of preformed vitamin A, which is more bioavailable to the body. - farming practices, which result in low quantities of retinol in meat. - poor health, which impairs liver storage of vitamin A. - high intake of beta-carotene, which cannot be converted into retinoic acid.

- low intake of preformed vitamin A, which is more bioavailable to the body.

Physicians sometimes prescribe niacin in high doses to: - help smokers quit smoking. - lower LDL cholesterol. - prevent numbness and nerve damage. - improve immune function. - prevent damage to cells due to free radicals.

- lower LDL cholesterol.

Which of the following groups is LEAST likely to experience increased vitamin requirements? - pregnant women - growing children - people with infections - lactating women - middle-aged men

- middle-aged men

Which choice only includes vitamins that can have toxic effects if consumed in excess? - vitamin B6, vitamin B12, folate - niacin, vitamin B6, vitamin C - folate, niacin, vitamin B6, vitamin B12 - riboflavin, niacin, vitamin B6

- niacin, vitamin B6, vitamin C

An early sign of vitamin A deficiency is: - carotenemia. - hypervitaminosis A. - night blindness. - infectious diseases. - keratinization.

- night blindness.

Vitamin D deficiency in adults results in: - rickets. - osteomalacia. - hypervitaminosis D. - oxidative damage. - cancer.

- osteomalacia.

A deficiency of what vitamin will NOT cause anemia? - folate - pantothenic acid - vitamin B12 - vitamin B6

- pantothenic acid

Which vitamin rarely results in a deficiency because of its presence in a wide variety of plant and animal sources? - biotin - pantothenic acid - vitamin C - vitamin B12 - vitamin B6

- pantothenic acid

All of the following nutrients are correctly matched with one of their primary functions EXCEPT: - vitamin B6—amino acid metabolism. - choline—incorporation into cell membranes. - niacin—DNA repair. - pantothenic acid—antioxidant.

- pantothenic acid—antioxidant.

Which does NOT play a role in maintaining blood concentrations when calcium levels are low? - parathyroid hormone increasing kidney production of active vitamin D - parathyroid hormone increasing intestinal production of active vitamin D - activated vitamin D increasing intestinal absorption calcium - activated vitamin D decreasing kidney excretion of calcium - activated vitamin D increasing release of calcium from the bone

- parathyroid hormone increasing intestinal production of active vitamin D

Inactive forms of vitamins that are activated once in the body are called: - precursor vitamins. - preformed vitamins. - pre-vitamins. - provitamins.

- provitamins.

All of the following are recommended practices to preserve vitamins in food EXCEPT: - purchase milk in opaque containers to prevent light from destroying riboflavin. - use minimal water and time to cook vegetables. - refrigerate fruits and vegetables to slow the breakdown of some vitamins. - remove the peel from fruits and vegetables.

- remove the peel from fruits and vegetables.

Which action does not preserve water-soluble vitamins in foods? - freezing - refrigerating - storing in airtight containers - removing the peel from fruits and vegetables - reducing use of water and using shorter times when cooking

- removing the peel from fruits and vegetables

Which of the following is an active form of vitamin A? - beta-carotene - tocopherol - calcitriol - retinoic acid

- retinoic acid

Milk is packaged in opaque containers to prevent light from destroying: - thiamin. - riboflavin. - niacin. - biotin. - vitamin B6.

- riboflavin.

Which is the richest food source of vitamin D? - salmon (3 oz) - milk (1 cup) - fortified orange juice (1 cup) - cheese (1 slice) - egg (1 large)

- salmon (3 oz)

Seth has a family history of skin cancer and avoids direct sunlight. To prevent vitamin D deficiency, Seth should increase his intake of: - salmon. - almonds. - lean beef. - orange juice.

- salmon.

Which foods contain the least amount of vitamin B12? - clams and other shellfish - ground beef - milk and dairy products - spinach and leafy green vegetables - eggs and poultry

- spinach and leafy green vegetables

Which of the following would be LEAST likely to affect the bioavailability of a nutrient in a food? - other foods consumed with the nutrient - the type of material (ceramic, plastic, metal, etc.) the food is served on - cooking or chopping the food - the food source of the nutrient

- the type of material (ceramic, plastic, metal, etc.) the food is served on

Vitamin A deficiency leads to night blindness because: - the nerve impulse to the brain is delayed. - the rod cells are less protected from UV radiation from sunlight. - cis-retinal cannot be converted to trans-retinal. - there is a less efficient response to recharge rhodopsin.

- there is a less efficient response to recharge rhodopsin.

The difference between cis-retinal and trans-retinal is: - they have different conformations of double-bonds. - they combine with opsin at different sites. - cis-retinal is more efficiently paired with opsin than trans-retinal. - cis-retinal is straight, whereas trans-retinal is bent.

- they have different conformations of double-bonds.

In carbohydrate metabolism, pyruvate dehydrogenase is activated by thiamin so that it can convert pyruvate into acetyl coenzyme A. Which component is the coenzyme in this example? - pyruvate - acetyl coenzyme A - pyruvate dehydrogenase - thiamin

- thiamin

Wernicke-Korsakoff syndrome results from: - thiamin deficiency due to alcoholism. - niacin deficiency due to low protein intake. - vitamin B6 due to low consumption of organ meats. - riboflavin deficiency due to low dairy intake. - vitamin C due to low fruit and vegetable consumption.

- thiamin deficiency due to alcoholism.

A patient with a poor diet shows fatigue, muscle weakness and pain, and emotional disturbances, suggesting a possible: - thiamin deficiency. - niacin deficiency. - vitamin B6 deficiency. - vitamin B12 deficiency. - folate deficiency.

- thiamin deficiency.

Which list contains only vitamins that play a role in RNA and DNA synthesis? - thiamin, riboflavin, niacin - thiamin, folate, niacin - vitamin B6, vitamin B12, folate - vitamin B6, vitamin B12, vitamin C - biotin, pantothenic acid, riboflavin

- thiamin, folate, niacin

All of the following correctly match the vitamin with one of its highest natural food sources EXCEPT: - folate—beans. - niacin—poultry. - riboflavin—dairy products. - thiamin—fish.

- thiamin—fish.

Which of the following is NOT a way of preserving vitamins in foods? - refrigerating foods in airtight, moisture-proof containers - using plenty of water when preparing and cooking foods - eating fruits and vegetables as soon as possible after harvesting or purchase - avoiding peeling fruits like apples and pears - cooking fresh fruits and vegetables on low heat and avoiding long heat exposure

- using plenty of water when preparing and cooking foods

Too much of which vitamin can result in birth defects? - vitamin A - carotenoids - vitamin K - vitamin D - vitamin E

- vitamin A

We consume significant amounts of what vitamin in its most inactive form? - vitamin A - vitamin K - vitamin D - vitamin E

- vitamin A

What vitamin is the MOST toxic when consumed in excess? - vitamin D - vitamin K - vitamin E - vitamin A

- vitamin A

What choice correctly matches the vitamin with one of its primary functions? - vitamin E—blood clotting - vitamin K—regulation of blood calcium - vitamin A—cell development - vitamin D—antioxidant

- vitamin A—cell development

What vitamin occurs naturally only in animal products? - vitamin B12 - niacin - vitamin B6 - thiamin

- vitamin B12

Which of the following nutrients does NOT play a direct role in the production of neurotransmitters? - choline - vitamin B6 - pantothenic acid - vitamin B12

- vitamin B12

Which water-soluble vitamin can be stored in the body? - vitamin C - niacin - folate - vitamin B12 - thiamin

- vitamin B12

Pernicious anemia is the result of: - thiamin deficiency. - niacin deficiency. - vitamin B12 deficiency. - choline deficiency. - vitamin C deficiency.

- vitamin B12 deficiency.

Excess of which water-soluble vitamin can cause a long-term toxic effect of numbness due to nerve damage? - thiamin - vitamin C - pantothenic acid - vitamin B6 - choline

- vitamin B6

Which list contains only vitamins that can have toxic effects if consumed in excess? - thiamin and riboflavin - vitamin B12 and folate - thiamin and biotin - vitamin B6 and vitamin C - biotin and vitamin B12

- vitamin B6 and vitamin C

Which list contains only vitamins that play a role in red blood cell health? - thiamin, riboflavin, vitamin B12 - niacin, vitamin B6, vitamin C - vitamin B6, vitamin B12, folate - niacin, vitamin B6, choline - vitamin B6, vitamin B12, biotin

- vitamin B6, vitamin B12, folate

All of the following vitamins play a critical role in DNA synthesis EXCEPT: - folate. - vitamin B12. - vitamin B6. - thiamin.

- vitamin B6.

Which choice INCORRECTLY pairs the vitamin with the name of its deficiency disease? - riboflavin—ariboflavinosis - vitamin C—scurvy - niacin—pellagra - vitamin B6—beriberi

- vitamin B6—beriberi

Scurvy is a disease resulting from: - thiamin deficiency due to alcoholism. - niacin deficiency due to low protein intake. - vitamin B6 deficiency due to low consumption of organ meats. - riboflavin deficiency due to low dairy intake. - vitamin C deficiency due to low fruit and vegetable consumption.

- vitamin C deficiency due to low fruit and vegetable consumption.

A patient showing poor wound healing, bruising, joint pain, and bleeding gums may have a deficiency of: - thiamin. - niacin. - vitamin B6. - vitamin B12. - vitamin C.

- vitamin C.

Which choice INCORRECTLY pairs the common name of the vitamin with its chemical name? - vitamin B12—cobalamin - vitamin C—citric acid - vitamin B6—pyridoxine - All of these are incorrectly paired.

- vitamin C—citric acid

What fat-soluble vitamin can be synthesized by our body's cells? - vitamin D - vitamin E - vitamin K - vitamin A

- vitamin D

Which vitamin can be synthesized in significant amounts by humans? - vitamin D - vitamin E - ascorbic acid - retinoic acid - carotenoids

- vitamin D

Which vitamins play a role in bone health? - vitamin E and vitamin K - vitamin E and carotenoids - vitamin D and vitamin E - vitamin D and vitamin K - vitamin D and carotenoids

- vitamin D and vitamin K

What choice correctly matches the vitamin with its best dietary sources? - vitamin E—fruit - vitamin K—orange-colored fruits and vegetables - vitamin A—oils and nuts - vitamin D—fortified foods and fish

- vitamin D—fortified foods and fish

What fat-soluble vitamin performs NO regulatory function? - vitamin K - vitamin D - vitamin E - vitamin A

- vitamin E

Which of the following may protect against free radicals? - sedentary lifestyle - exposure to UV radiation - compromised immune function - vitamin E supplementation - cigarette smoking

- vitamin E supplementation

A deficiency of what vitamin is NOT expected to affect immune function in any way? - vitamin A - vitamin D - vitamin E - vitamin K

- vitamin K

What vitamin has no established UL? - vitamin D - vitamin A - vitamin E - vitamin K

- vitamin K

What vitamin plays a key role in both blood clotting and bone formation? - vitamin E - vitamin K - vitamin A - vitamin D

- vitamin K

Which can be produced by intestinal bacteria? - vitamin A - vitamin D - vitamin K - vitamin E - tocopherol

- vitamin K

Which fat-soluble vitamin has no established Upper Tolerable Intake Level (UL)? - vitamin A - vitamin K - vitamin D - vitamin E - both vitamins A and K

- vitamin K

Which of these conditions can increase the tendency to bleed? - vitamin A toxicity - vitamin D deficiency - vitamin E deficiency - vitamin K deficiency - vitamin D and vitamin K deficiencies

- vitamin K deficiency

Antibiotic use can result in reduced synthesis of: - vitamin A. - vitamin D. - vitamin E. - vitamin K. - carotenoids.

- vitamin K.

What choice INCORRECTLY pairs the signs and symptoms of deficiency with the correct vitamin? - vitamin D—poor bone development - vitamin E—impaired immune function - vitamin K—increased risk of cancer - vitamin A—blindness

- vitamin K—increased risk of cancer

What two vitamins function as hormones? - vitamins A and D - vitamins E and K - vitamins D and E - vitamins A and K

- vitamins A and D