Ch 12

Coenzymes play an important role in metabolism because they

aid in the function of activating enzymes.

A diet high in ______ may result in thiamin deficiency.

alcohol processed, unenriched foods

Molybdenum participates in

amino acid metabolism

Which source of vitamin B-6 has the highest bioavailability?

animal product

A person experiencing weakness, loss of appetite, poor coordination, and edema caused by lack of thiamin is experiencing the deficiency disease known as

Beriberi

The deficiency disease that causes scaly, inflamed skin, decreased appetite, nausea, vomiting, and weakness is due to a lack of which B-vitamin?

Biotin

Elevated levels of blood glucose, triglycerides, and cholesterol are clinical features of ______ deficiency.

Chromium

Glucose intolerance may be a sign of ______ deficiency.

Chromium

Megadoses of niacin are sometimes used to lower blood lipids in patients with cardiovascular disease. A risk of chronically exceeding the UL for niacin is damage to the

GI tract. liver.

What is the best food source for iodine?

Iodized salt, 1/2 tsp

Which of the following minerals participates in bone formation, antioxidant reactions, and metabolism of glucose and amino acids?

Manganese

______ is the choline-containing compound that helps to insulate nerve cells.

Sphingomyelin

Beriberi is a deficiency disease caused by a lack of

Thiamin

The B vitamin required as a coenzyme to release energy from carbohydrates and some amino acids is

Thiamin.

True or false: Riboflavin deficiency is usually accompanied by deficiencies of several other B vitamins.

True

Which of the following foods is the best source of niacin?

Tuna, 3 oz

The coenzyme form of ______ participates in more than 100 amino acid metabolism reactions, including homocysteine metabolism.

Vitamin B-6

The main function of molybdenum is

as part of a severa; human enzymes

The availability of biotin is limited by

avidin

Niacin is

a coenzyme in metabolic reactions that yield energy from food.

The protein called avidin in raw egg whites binds to ______ and inhibits its absorption.

biotin

The thiamin coenzyme is particularly important for the release of energy from

carbohydrates.

The coenzyme form of biotin functions to add ______ to compounds in metabolic reactions.

carbon dioxide

Choline's role in transfer of single-carbon groups during metabolic reactions influences risk for

cardiovascular disease. birth defects.

Phosphatidylcholine is a phospholipid that primarily functions in

cell membrane structure

A compound that combines with an inactive enzyme to form an active enzyme is called a(n)

coenzyme.

Food sources of riboflavin include

eggs. enriched grains. milk.

Rich food sources of biotin include

eggs. liver. peanuts.

The most nutrient-dense food source of choline is

egss

Which of the following is a function of chromium?

glucose uptake

Choline is involved in the transport of ______ through the blood.

lipids

Biotin deficiency is rare even when the dietary intake is low because biotin can be

synthesized by intestinal bacteria.

Nutrients are lost during refinement of grains because

the germ, bran, and husk are discarded.

A riboflavin deficiency usually occurs with a deficiency of several other B vitamins because

these nutrients often occur in the same foods.

Which two food groups supply the most thiamin in the typical American diet?

- Grains -Protein foods

Rich dietary sources of niacin include

- beef -poultry -fish

Which of the following body systems are affected by vitamin B-6 deficiency?

-Nervous -Immune -Cardiovascular

A deficiency of pantothenic acid may occur in

-an alcoholic. -a nutrient-deficient diet.

Functions of riboflavin include

-assisting antioxidant reactions. -release of energy from fatty acids.

Which of the following are characteristics of pellagra, the deficiency disease for niacin?

-diarrhea -dementia -dermatitis

The functions of manganese include

-energy metabolism. -bone formation. -free-radical metabolism.

The coenzyme form of pantothenic acid participates in

-fatty acid synthesis. -release of energy from carbohydrates, fats, and proteins.

Choline deficiency could lead to

-fatty liver -abnormal blood lipids

The body's needs for niacin are met by

-food sources. -synthesis from tryptophan.

Which two food groups provide the richest sources of vitamin B-6?

-grains -protein foods

High intakes of nicotinic acid can lead to

-headache. -facial flushing. -itching.

Which of the following are dietary sources of chromium?

-organ meat -beer -nuts

Which of the following are rich sources of iodine?

-processed meats -dairy products

Possible symptoms of biotin deficiency include ______.

-skin inflammation -nausea and vomiting -muscle pain and weakness

The functions of vitamin B-6 include

-synthesis of nonessential amino acids. -synthesis of neurotransmitters. -homocysteine metabolism.

The Adequate Intake for pantothenic acid for adults is ______ for adult men and women.

5 milligrams per day

The human body can synthesize niacin from an amino acid:______ mg of tryptophan can be converted into about 1 mg of niacin

60

______ is the choline-containing compound that functions as a neurotransmitter.

Acetylcholine

The coenzyme forms of ______ are integral to the metabolism of carbohydrates, lipids, and protein for energy.

B vitamins

Typical North American B vitamin status is good because

B vitamins are efficiently absorbed. sources of B-vitamins are plentiful. many foods are fortified with B vitamins.

Choline plays a role in synthesis of which of the following components of the cell membrane?

Phospholipids

Cow's milk is an excellent source of

Riboflavin

Which of the following B-vitamins plays a role in the body's antioxidant defense system as a coenzyme for glutathione peroxidase?

Riboflavin

Identify three food sources of thiamin.

Whole grains Pork Enriched flour

Choline is a precursor for ______, which transfers single-carbon groups in metabolic reactions.

betaine

A B-vitamin that functions in the addition of carbon dioxide to other compounds during the metabolism of glucose, fatty acids, and amino acids is

biotin

The thyroid gland uses ______ to synthesize thyroid hormones.

iodine

Milk and dairy products, beans, whole grains, and nuts are all good food sources of

molybdenum

Compared to refined or processed grains, whole grains contain

more vitamin E. more magnesium. more fiber.

The coenzyme forms of ______ are involved in breakdown and synthesis of fat and protein.

niacin

Which of the following B-vitamins functions in the release of energy from carbohydrates, lipids, and proteins as well as in fatty acid synthesis? Its name comes from the Greek word meaning "from every side."

pantothenic acid

B vitamins are required for

transamination of amino acids. synthesis of lipids. chemical breakdown of carbohydrates.

Because it is necessary for over 100 reactions in amino acid metabolism, a deficiency of ______ leads to widespread symptoms, including depression, skin disorders, and nerve problems.

vitamin B-6