Question 1

Which of the following statements is true?

Accepted Answer

Foods generally contain much smaller amounts of vitamins than proteins or carbohydrates. While vitamins are essential micronutrients, they are required in smaller quantities compared to macronutrients such as proteins and carbohydrates. Therefore, foods tend to contain smaller amounts of vitamins per serving.

Question 2

Which of the following statements is true?

Accepted Answer

Option A is true - Vitamins are organic micronutrients. Option B is false because foods generally supply larger amounts of proteins and carbohydrates than vitamins. Option C is false because vitamins D and A are fat-soluble, not water-soluble. Option D is false because the body excretes water-soluble vitamins through urine more easily than fat-soluble vitamins.

Question 3

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

The fact that the chemical supplies no energy for cells but protects cell membranes from damage by certain environmental factors suggests that it may be an antioxidant. Antioxidants are molecules that can prevent or slow damage to cells caused by free radicals, which are unstable molecules that can cause harm to cells. Since the chemical is water-soluble and organic, it is possible that it is a type of polyphenol, which are often found in plant-based foods and are known for their antioxidant properties.

Question 4

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 can build up in the body over time, leading to toxicity. In contrast, water-soluble vitamins are excreted through the kidneys and excess amounts are eliminated in the urine, making it less likely to cause toxicity.

Question 5

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

Accepted Answer

Antioxidants prevent or limit the ability of free radicals to damage polyunsaturated fatty acids and DNA in cells. Carcinogens are substances that can cause cancer. Megadoses refer to extremely high doses of a substance, which can also have negative effects. Coenzymes are molecules that help enzymes function properly.

Question 6

Which of the following statements is true about vitamins?

Accepted Answer

Compared to proteins and carbohydrates, your body requires very small quantities of vitamins. While it is true that vitamins occur naturally in foods, and some vitamins are fat-soluble (such as vitamins A, D, E, and K), it is not safe to consume megadoses of vitamins as they can be toxic.

Question 7

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

Since Damon is taking an antibiotic every day, it may affect the absorption of vitamin K, which is necessary for blood clotting. Therefore, he may need to take a dietary supplement that contains vitamin K to ensure adequate levels. There is no evidence to suggest that he needs to eat more vitamin-C rich foods, consume fewer foods that contain omega-3 fatty acids, or reduce his protein intake.

Question 8

_____ are fat-soluble vitamins.

Accepted Answer

The fat-soluble vitamins are vitamins D, E, A, and K. Option A includes two water-soluble vitamins, and options B and C contain only one fat-soluble vitamin.

Question 9

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

Accepted Answer

Free radicals are unstable molecules that can damage DNA and other molecules by stealing electrons from them. This can lead to oxidative stress and various diseases. Coenzymes are substances that assist enzymes in biochemical reactions, carotenoids are pigments that provide color to fruits and vegetables, and intrinsic factor is a protein that helps with vitamin B12 absorption.

Question 10

_____ 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 help replace some of the nutrients lost during refining.

Question 11

_____ are fat-soluble vitamins.

Accepted Answer

Vitamins K, D, and A are fat-soluble vitamins, which means they are absorbed and stored in the body's fatty tissues. Niacin, riboflavin, thiamin, B-12, B-6, E, pantothenic acid, and choline are all water-soluble vitamins, which means they are not stored in the body and excess amounts are typically eliminated in urine.

Question 12

_____ are water-soluble vitamins.

Accepted Answer

Vitamins such as pantothenic acid, vitamin C, and thiamin are water-soluble, meaning they dissolve in water and are not stored in the body in significant amounts, requiring regular intake through diet.

Question 13

_____ are water-soluble vitamins.

Accepted Answer

Niacin, riboflavin, and thiamin are all water-soluble vitamins. Vitamins B-12, B-6, and E are all also vitamins, but they are not water-soluble. Vitamins K, D, and E are fat-soluble vitamins. Pantothenic acid and choline are also vitamins but are not water-soluble.

Question 14

_____ are fat-soluble vitamins.

Accepted Answer

Vitamins K, E, and D are fat-soluble vitamins. This means that they are stored in the body's fatty tissue and liver and are not excreted as easily as water-soluble vitamins. They require the presence of dietary fat to be absorbed and utilized by the body.

Question 15

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

Accepted Answer

An antioxidant is a substance that protects vulnerable molecules from free radicals. Free radicals are unstable molecules that can damage cells, leading to aging and disease. Antioxidants neutralize free radicals by donating an electron, preventing them from damaging other molecules.

Question 16

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

Accepted Answer

Bile breaks down large fat globules into smaller droplets, increasing the surface area for enzymes to break down and enhancing the absorption of fat-soluble vitamins (A, D, E, and K) in the small intestine. Pancreatic amylase breaks down carbohydrates, pepsin breaks down proteins, and hydrochloric acid helps activate enzymes but does not directly enhance the absorption of fat-soluble vitamins.

Question 17

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

Accepted Answer

Beta-carotene is a provitamin for Vitamin A.

Question 18

The human body can absorb some _____ that's made by intestinal bacteria.

Accepted Answer

Biotin is a vitamin that is produced by bacteria in the large intestines of humans. While some biotin is made in the body naturally, it's believed that most people get the majority of their biotin from intestinal bacteria. Vitamin C, beta-carotene, and riboflavin are not produced by intestinal bacteria and must be obtained through the diet or supplements.

Question 19

The body can store large amounts of ____ in the liver.

Accepted Answer

The body can store large amounts of vitamin B-12 in the liver, but it cannot store large amounts of vitamin C, riboflavin, or thiamin.

Question 20

The human body can absorb some of the _____ that's made by intestinal bacteria.

Accepted Answer

Intestinal bacteria produce vitamin K, which can be absorbed by the human body.

Quiz 8: Vitamins: Nutrients That Multitask

Which of the following statements is true?

Which of the following statements is true?

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

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

Which of the following statements is true about vitamins?

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

_____ are fat-soluble vitamins.

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

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

_____ are fat-soluble vitamins.

_____ are water-soluble vitamins.

_____ are water-soluble vitamins.

_____ are fat-soluble vitamins.

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

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

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

The human body can absorb some _____ that's made by intestinal bacteria.

The body can store large amounts of ____ in the liver.

The human body can absorb some of the _____ that's made by intestinal bacteria.