Question 1

Why is taking excess amounts of fat-soluble vitamins more likely to cause toxicity than taking excesses of water-soluble vitamins?

Accepted Answer

Excesses of fat-soluble vitamins cannot be excreted as easily as water-soluble vitamins because they are stored in fatty tissues and the liver, where they can accumulate and cause toxicity over time. Water-soluble vitamins, on the other hand, are excreted in urine and are less likely to accumulate in the body.

Question 2

_____ are water-soluble vitamins.

Accepted Answer

Pantothenic acid, vitamin C, and thiamin are all water-soluble vitamins. Vitamin D, A, and E are fat-soluble vitamins and riboflavin is also a water-soluble vitamin, but vitamin A is not. Vitamin K and niacin are also water-soluble vitamins but they are not listed as an option.

Question 3

_____ are fat-soluble vitamins.

Accepted Answer

Vitamins K, D, and A are all fat-soluble vitamins, meaning they are absorbed and stored in the body's fatty tissue.

Question 4

_____ are fat-soluble vitamins.

Accepted Answer

Vitamins K, E, and D are fat-soluble vitamins, meaning they require dietary fat for absorption and are stored in adipose tissue, liver, and other fatty tissues in the body. Niacin, riboflavin, and thiamin are water-soluble vitamins that are not stored in the body and must be replenished regularly. Pantothenic acid, vitamin A, and choline are also water-soluble vitamins. Vitamins B-12, B-6, and E are not water-soluble, but only vitamin E is classified as a fat-soluble vitamin.

Question 5

_____ is added to refined grain products as part of the enrichment process.

Accepted Answer

Thiamin is added to refined grain products as part of the enrichment process to replace the nutrients that were lost during the refining process.

Question 6

A researcher has isolated an organic,water-soluble chemical from roses.After performing tests,the scientist determines that the chemical supplies no energy for cells,but protects cell membranes from being damaged by certain environmental factors.Based on this information,the researcher may have discovered a (an)

Accepted Answer

An antioxidant is a substance that protects cells from damage caused by free radicals and other environmental stressors. The fact that the chemical isolated from roses supplies no energy for cells but protects cell membranes from damage suggests that it may act as an antioxidant. Amino acids are the building blocks of proteins and are unlikely to be water-soluble organic chemicals from roses. Teratogens are substances that can cause birth defects and have nothing to do with the properties of the isolated chemical. Free radicals are highly reactive compounds that can damage cells, but the chemical isolated from roses appears to protect against such damage.

Question 7

The body can store large amounts of

Accepted Answer

Vitamin B-12 is the only nutrient listed that can be stored in the body in large amounts. Vitamin A, riboflavin, and thiamin are all water-soluble vitamins that are not stored in significant amounts and require regular intake.

Question 8

The human body can absorb some of the _____ that is synthesized by intestinal bacteria.

Accepted Answer

Intestinal bacteria synthesize vitamin K, which the human body can absorb. The other options are not synthesized by intestinal bacteria.

Question 9

Which of the following statements is true?

Accepted Answer

Vitamins are essential nutrients required by the body in small amounts for normal metabolism, growth and development. While they are important, they are required in smaller amounts than proteins or carbohydrates. Therefore, statement C is true while A, B, and D are false.

Question 10

A(An)_____ is a substance that protects vulnerable molecules from free radicals.

Accepted Answer

Antioxidants are substances that protect vulnerable molecules from free radicals, which are unstable molecules that can damage cells and contribute to aging and diseases like cancer.

Question 11

Damon has a chronic illness,and to treat the condition,he takes an antibiotic every day.Despite his illness,Damon's diet is nutritionally adequate,and he exercises regularly.Based on this information,Damon may need to

Accepted Answer

Chronic antibiotic use can disrupt the normal gut flora, which can interfere with the production and absorption of vitamin K. Therefore, taking a dietary supplement that contains vitamin K may be necessary to ensure adequate levels of this nutrient. The other options (reducing protein intake, increasing vitamin C, consuming fewer omega-3 fatty acids) are not directly related to Damon's chronic illness or antibiotic use.

Question 12

______ prevent or limit the ability of free radicals to damage polyunsaturated fatty acids and DNA in cells.

Accepted Answer

Antioxidants have the ability to prevent or limit the ability of free radicals to damage polyunsaturated fatty acids and DNA in cells. Free radicals are unstable molecules that can damage cells and contribute to the development of diseases such as cancer, heart disease, and Alzheimer's disease. Antioxidants neutralize free radicals by donating an electron, thus preventing or limiting the damage they can cause. Examples of antioxidants include vitamins C and E, beta-carotene, and selenium.

Question 13

A(An)_____ is a chemically unstable substance that can damage vulnerable molecules,such as DNA.

Accepted Answer

Free radicals are chemically unstable substances with unpaired electrons that can damage vulnerable molecules in the body, such as DNA. Intrinsic factor is a protein necessary for the absorption of vitamin B12, coenzyme is a molecule that helps enzymes function, and carotenoids are pigments found in fruits and vegetables.

Question 14

The human body can absorb some _____ that is synthesized by intestinal bacteria.

Accepted Answer

Biotin is synthesized by intestinal bacteria, and human body can absorb and use it. Vitamin C is not synthesized by intestinal bacteria but can be obtained from dietary sources. Riboflavin and beta-carotene are not synthesized by intestinal bacteria and must be obtained from dietary sources.

Question 15

Which of the following substances enhances fat-soluble vitamin absorption in the small intestine?

Accepted Answer

Bile is produced in the liver and stored in the gallbladder. It emulsifies fats into smaller droplets, increasing their surface area and making them easier to digest and absorb in the small intestine. Bile also aids in the absorption of fat-soluble vitamins (A, D, E, and K) by incorporating them into micelles, which are small structures that can pass through the intestinal wall and into the bloodstream. Hydrochloric acid, pepsin, and pancreatic amylase are not directly involved in the absorption of fat-soluble vitamins.

Question 16

_____ are fat-soluble vitamins.

Accepted Answer

Vitamins D and E are fat-soluble, meaning they can be stored in the body's fatty tissues and liver. The other options listed are water-soluble vitamins, which are not stored in the body and must be consumed regularly.

Question 17

_____ are water-soluble vitamins.

Accepted Answer

Niacin, riboflavin, and thiamin are all water-soluble vitamins. Vitamins K, D, and E are fat-soluble vitamins, while pantothenic acid, vitamin A, and choline can be either water-soluble or fat-soluble depending on their chemical structure. Vitamin B-12 and B-6 are also water-soluble vitamins, but vitamin E is fat-soluble.

Question 18

Which of the following statements is true about vitamins?

Accepted Answer

Compared to proteins and carbohydrates, our body requires very small quantities of vitamins. While vitamins are essential for our health, they are only required in small amounts, typically measured in milligrams or micrograms. Consuming excessive amounts of vitamins (megadoses) can be harmful to our health. Thiamin, riboflavin, and pantothenic acid are water-soluble vitamins, not fat-soluble as stated in option D. Option A is incorrect as vitamins occur naturally in many foods, especially fruits and vegetables.

Question 19

Which of the following substances is a provitamin or a precursor for a vitamin?

Accepted Answer

Beta-carotene is a provitamin or a precursor for vitamin A. Once it is converted to vitamin A in the body, it functions in maintaining healthy vision, immune function, and skin health. Collagen is a protein found in skin and connective tissues, biotin is a B vitamin important for hair, skin, and nail health, and alpha-tocopherol is a form of vitamin E known for its antioxidant properties, but none of them are provitamins or precursors for other vitamins.

Question 20

Which of the following statements is true?

Accepted Answer

Vitamins are indeed organic micronutrients.

Quiz 8: Vitamins: Nutrients That Multitask

Why is taking excess amounts of fat-soluble vitamins more likely to cause toxicity than taking excesses of water-soluble vitamins?

_____ are water-soluble vitamins.

_____ are fat-soluble vitamins.

_____ are fat-soluble vitamins.

_____ is added to refined grain products as part of the enrichment process.

The body can store large amounts of

The human body can absorb some of the _____ that is synthesized by intestinal bacteria.

Which of the following statements is true?

A(An) _____ is a substance that protects vulnerable molecules from free radicals.

Damon has a chronic illness,and to treat the condition,he takes an antibiotic every day.Despite his illness,Damon's diet is nutritionally adequate,and he exercises regularly.Based on this information,Damon may need to

______ prevent or limit the ability of free radicals to damage polyunsaturated fatty acids and DNA in cells.

A(An) _____ is a chemically unstable substance that can damage vulnerable molecules,such as DNA.

The human body can absorb some _____ that is synthesized by intestinal bacteria.

Which of the following substances enhances fat-soluble vitamin absorption in the small intestine?

_____ are fat-soluble vitamins.

_____ are water-soluble vitamins.

Which of the following statements is true about vitamins?

Which of the following substances is a provitamin or a precursor for a vitamin?

Which of the following statements is true?