Nutrition HW 4.2

Vitamin B-12 absorption involves compounds from the salivary glands, stomach, and small intestine. Put the steps of vitamin B-12 digestion and absorption in order as they occur in the body.

1. Vitamin B-12 in food enters the stomach and is digested somewhat by stomach acid. 2. Free vitamin B-12 in the stomach binds with an R-protein produced by the salivary glands, protecting vitamin B-12 from total destruction by stomach acid 3. Bound vitamin B-12 is freed from the R-protein in the small intestine 4. In the small intestine, vitamin B-12 binds with intrinsic factor, which is made in the stomach 5. The vitamin B-12/intrinsic factor complex travels to the end of the small intestine, where about 50% of the total dietary vitamin B-12 is then absorbed, depending upon how much the body needs

In general, excess amounts of water-soluble vitamins are excreted via the A. Kidneys B. Intestines C. Lungs D. Skin

A

Insufficient intake of vitamins can result in a variety of deficiency diseases. Match the symptoms with the most likely vitamin deficiency based on information obtained about each patient. ~Patient presents with double vision, ataxia, hallucinations and memory loss. A family member confirms that they are a long-time heavy user of alcohol. A. thiamin B. riboflavin C. vitamin C D. vitamin B-12 E. niacin

A

Match each water-soluble vitamin to the coenzyme that it forms: thiamin A. thiamin pyrophosphate B. nicotinamide adenine dinucleotide C. flavin adenine dinucleotide D. methylcobalamin E. coenzyme A F. pyridoxal phosphate

A

Match the water-soluble vitamin with its function in cellular metabolism. ~Functions in the exchange of single carbon groups A. Folate B. Pantothenic acid C. Thiamin D. Riboflavin E. Biotin F. Vitamin C

A

Which of the following statements is true in relation to pantothenic acid? A. Pantothenic acid is a component of coenzyme A B. Pantothenic acid is found only in foods of animal origin. C. Pantothenic acid should not be supplemented in foods because it can often be toxic D. Pantothenic acid deficiency is common in many parts of the world.

A

Anemia can result from deficiency of a number of different micronutrients. Features of the red blood cells, such as size and color, can help health professionals to determine the cause of anemia. Classify the following micronutrients based on whether deficiencies lead to macrocytic (megaloblastic) or microcytic anemia. Which lead to macrocytic anemia? A. Vitamin B-12 B. Vitamin B-6 C. Folate

A C

The B-vitamin content of a whole grain is dramatically decreased during the refining process. To counteract these losses, in the United States, food manufacturers are required to enrich or fortify breads and cereals from milled, refined grains with which B-vitamins? (Check all that apply): A. niacin B. vitamin B-6 C. riboflavin D. thiamin E. folic acid

A C D E (Bread and cereal products made from milled grains in the United States are enriched or fortified with four B-vitamins: thiamin, riboflavin, niacin, and folic acid. They are also enriched with one mineral - iron.)

Although it is an essential nutrient, the body is able to synthesize niacin to meet some body needs from the amino acid tryptophan. This reaction requires which two other B-vitamins as coenzymes? Check all that apply. A. thiamin B. riboflavin C. vitamin B-6 D. vitamin B-12

B C (The body is able to synthesize 1 mg niacin from 60 mg of tryptophan in a chemical reaction that employs riboflavin and vitamin B-6 as coenzymes.)

Anemia can result from deficiency of a number of different micronutrients. Features of the red blood cells, such as size and color, can help health professionals to determine the cause of anemia. Classify the following micronutrients based on whether deficiencies lead to macrocytic (megaloblastic) or microcytic anemia. Which lead to microcytic anemia? A. Vitamin B-12 B. Vitamin B-6 C. Folate

B

Insufficient intake of vitamins can result in a variety of deficiency diseases. Match the symptoms with the most likely vitamin deficiency based on information obtained about each patient. ~Patients presents with stomatitis (mouth inflammation) glossitis (tongue inflammation) and, upon review of medications used, it is found that they have a long history of phenobarbital use A. thiamin B. riboflavin C. vitamin C D. vitamin B-12 E. niacin

B

Match each water-soluble vitamin to the coenzyme that it forms: niacin A. thiamin pyrophosphate B. nicotinamide adenine dinucleotide C. flavin adenine dinucleotide D. methylcobalamin E. coenzyme A F. pyridoxal phosphate

B

Match the water-soluble vitamin with its function in cellular metabolism. ~Is a part of the molecule acetyl CoA A. Folate B. Pantothenic acid C. Thiamin D. Riboflavin E. Biotin F. Vitamin C

B

Nutritionally, the difference between brown rice and white rice is A. negligible. There is a little more thiamin in white rice than brown rice. B. the presence of bran and germ layers in the brown rice, which have most of the nutrients. C. fiber content. White rice has more fiber. D. there is more thiamin and fiber in white rice.

B

Insufficient intake of vitamins can result in a variety of deficiency diseases. Match the symptoms with the most likely vitamin deficiency based on information obtained about each patient. ~Following a high-protein diet that doesn't allow for the eating of fruits or vegetables, patient presents with pinpoint hemorrhages, bleeding gums and bone pain A. thiamin B. riboflavin C. vitamin C D. vitamin B-12 E. niacin

C

Match each water-soluble vitamin to the coenzyme that it forms: riboflavin A. thiamin pyrophosphate B. nicotinamide adenine dinucleotide C. flavin adenine dinucleotide D. methylcobalamin E. coenzyme A F. pyridoxal phosphate

C

Match the water-soluble vitamin with its function in cellular metabolism. ~Removes carbon dioxide from compounds such as pyruvate A. Folate B. Pantothenic acid C. Thiamin D. Riboflavin E. Biotin F. Vitamin C

C

The B-vitamin intake of most North Americans is adequate because B-vitamins are widespread in our diets. However, which of the following population groups is most susceptible to overt deficiencies of B-vitamins? A. People with fat malabsorption B. Vegetarians C. Alcoholics D. Smokers

C (Because of extremely unbalanced food intake and alcohol-induced alterations in B-vitamin absorption and metabolism, people with alcoholism are at greatest risk for B-vitamin deficiency syndromes.)

A cooking class instructor states that certain preparation and cooking methods can help preserve water-soluble vitamin content of vegetables. Which of the following practices is most likely to preserve the vitamin content of foods? A. Adding baking soda to green beans to preserve the green color B. Chopping fresh vegetables ahead of time and letting them rest on the counter while preparing the rest of the meal C. Cooking vegetables in minimal water for a brief period D. Boiling vegetables in water for a long period of time

C (The water-soluble vitamins - particularly thiamin, vitamin C, and folate - can be destroyed with improper storage and excessive cooking. Heat, light, exposure to the air, cooking in water, and alkalinity are all factors that can destroy vitamins.)

A characteristic symptom of niacin deficiency is A. cracks at the corner of the mouth B. a purple-red tongue C. severe edema D. inflammation of the skin after exposure to the sun

D

Bright yellow urine usually is indicative that someone is supplementing with A. niacin B. vitamin A C. vitamin K D. riboflavin

D

Insufficient intake of vitamins can result in a variety of deficiency diseases. Match the symptoms with the most likely vitamin deficiency based on information obtained about each patient. ~Patient present with pernicious anemia and neurological symptoms and reports following a strict vegan diet A. thiamin B. riboflavin C. vitamin C D. vitamin B-12 E. niacin

D

Match each water-soluble vitamin to the coenzyme that it forms: vitamin B-12 A. thiamin pyrophosphate B. nicotinamide adenine dinucleotide C. flavin adenine dinucleotide D. methylcobalamin E. coenzyme A F. pyridoxal phosphate

D

Match the water-soluble vitamin with its function in cellular metabolism. ~Participates in oxidation and reduction reactions in energy metabolism A. Folate B. Pantothenic acid C. Thiamin D. Riboflavin E. Biotin F. Vitamin C

D

The vitamin that prevents beriberi is A. vitamin B-12 B. riboflavin C. niacin D. thiamin

D

Gabe was reading an article in a muscle magazine that said a particular world-champion body builder regularly eats a dozen raw egg whites per day. From his recent nutrition studies, Gabe surmised that the body builder is at risk for developing which vitamin deficiency and why? A. Vitamin D deficiency because a protein in raw egg whites binds vitamin D and inhibits its absorption. B. Niacin deficiency because a protein in raw egg whites binds niacin and inhibits its absorption. C. Choline deficiency because a protein in raw egg whites binds choline and inhibits its absorption. D. Biotin deficiency because a protein in raw egg whites binds biotin and inhibits its absorption.

D (A protein called avidin in raw egg whites binds biotin and inhibits its absorption. Consuming many raw egg whites eventually leads to the deficiency disease. Cooking denatures avidin in eggs such that it cannot bind biotin.)

Insufficient intake of vitamins can result in a variety of deficiency diseases. Match the symptoms with the most likely vitamin deficiency based on information obtained about each patient. ~Patient presents with rough, red rash and the three Ds: dermatitis, diarrhea, and dementia. Upon review of diet history, it is found that the patient is eating primarily corn to meet energy needs due to limited income to purchase food A. thiamin B. riboflavin C. vitamin C D. vitamin B-12 E. niacin

E

Match each water-soluble vitamin to the coenzyme that it forms: pantothenic acid A. thiamin pyrophosphate B. nicotinamide adenine dinucleotide C. flavin adenine dinucleotide D. methylcobalamin E. coenzyme A F. pyridoxal phosphate

E

Match the water-soluble vitamin with its function in cellular metabolism. ~Adds carbon dioxide to compounds such as pyruvate A. Folate B. Pantothenic acid C. Thiamin D. Riboflavin E. Biotin F. Vitamin C

E

Match each water-soluble vitamin to the coenzyme that it forms: vitamin B-6 A. thiamin pyrophosphate B. nicotinamide adenine dinucleotide C. flavin adenine dinucleotide D. methylcobalamin E. coenzyme A F. pyridoxal phosphate

F

Match the water-soluble vitamin with its function in cellular metabolism. ~Donates electrons to iron and copper metal ions A. Folate B. Pantothenic acid C. Thiamin D. Riboflavin E. Biotin F. Vitamin C

F

T or F: Supplemental vitamin B-6, vitamin B-12, and folic acid can reduce blood levels of homocysteine, but have not been definitively proven to reduce the risk of cardiovascular disease.

T