DH 209 Nutrition Exam

Correct Answer:

A. Triglycerides

Explanation of the Correct Answer:

Triglycerides are fats, not carbohydrates. They are the main form of lipids (fats) found in the body and food. A triglyceride is made up of one molecule of glycerol and three molecules of fatty acids. They are primarily used for energy storage and provide more energy per gram than carbohydrates. Since triglycerides are fats and not carbohydrates, they do not fall into any classification of carbohydrates.

Why the Other Options Are Correct Classifications of Carbohydrates:

B. Polysaccharides

Polysaccharides are complex carbohydrates made up of many sugar molecules (monosaccharides) bonded together. Common examples include starch, glycogen, and cellulose. They are the body's primary way of storing energy (e.g., in muscles and the liver for glycogen). They are classified as carbohydrates because they consist of sugar units linked together.

C. Disaccharides

Disaccharides are simple carbohydrates made up of two monosaccharide units. Examples include sucrose (table sugar), lactose (milk sugar), and maltose (found in some grains). Disaccharides are broken down into their monosaccharide components by enzymes in the digestive system.

D. Monosaccharides

Monosaccharides are the simplest form of carbohydrates, consisting of a single sugar molecule. Examples include glucose, fructose, and galactose. These are the building blocks for more complex carbohydrates (like disaccharides and polysaccharides) and provide the body with quick energy.

Correct Answer:

D. First is true, second false

Explanation of the Correct Answer:

Xylitol is indeed a sugar alcohol, and it does not contribute to tooth decay because oral bacteria are not able to ferment it. While other sugars can be fermented by oral bacteria, leading to acid production and potential tooth decay, xylitol is different. Oral bacteria cannot ferment xylitol, so it does not contribute to the production of acid that causes decay. In fact, xylitol can actually inhibit the growth of bacteria that cause cavities.

Why the Other Options Are Incorrect:

A. First is false, second true

This option is incorrect because the first statement is true: xylitol is a sugar alcohol. However, the second part is false because xylitol does not contribute to tooth decay.

B. Both are false

This option is incorrect because the first statement is true: xylitol is a sugar alcohol. However, the second statement is false because xylitol does not contribute to tooth decay.

C. Both are true

This option is incorrect because, while xylitol is a sugar alcohol, it does not contribute to tooth decay as oral bacteria cannot ferment it.

Summary:

Xylitol is a sugar alcohol, but it does not contribute to tooth decay because oral bacteria are unable to ferment it. Therefore, the correct answer is D: the first statement is true, and the second is false.

Correct Answer:

A. First true, second false

Explanation of the Correct Answer:

Glossitis, an inflammation of the tongue, does result in slight atrophy of the circumvallate papillae, which can lead to a smooth appearance of the tongue due to the loss of these papillae. It can cause pain, redness, and swelling. However, the second part of the statement regarding the "magic mouthrinse" is inaccurate. Magic mouthrinse typically refers to a solution that may include ingredients like lidocaine, an antihistamine, and/or a corticosteroid, but it does not generally include Listerine and baking soda. The combination of Listerine and baking soda is not a standard or recommended treatment for glossitis or its associated pain.

Why the Other Options Are Incorrect:

B. Both are false

This option is incorrect because the first statement about glossitis resulting in slight atrophy of the circumvallate papillae is true, though the second statement about the use of Listerine and baking soda is false.

C. Both are true

This option is incorrect because the second part of the statement about magic mouthrinse being a combination of Listerine and baking soda is false. Magic mouthrinse typically includes other ingredients.

D. First false, second true

This option is incorrect because the first statement about glossitis causing atrophy of the circumvallate papillae is true, but the second statement about using Listerine and baking soda as magic mouthrinse is false.

Summary:

Glossitis does cause slight atrophy of the circumvallate papillae, resulting in a smooth appearance of the tongue. However, the statement about magic mouthrinse being a combination of Listerine and baking soda is false. Magic mouthrinse typically involves different ingredients for pain relief.

Correct Answer: A. Men

Explanation of the Correct Answer:

A is correct because men generally have the lowest Recommended Dietary Allowance (RDA) for iron. Iron requirements are lower in men than in women due to differences in physiological processes. Men do not have the monthly menstrual losses that women in their reproductive years experience, so their iron needs are comparatively lower. The RDA for men is about 8 mg per day.

Why the Other Options are Incorrect:

B. Perimenopausal women

This is incorrect because perimenopausal women generally have an increased iron requirement due to hormonal changes. Although they may still experience menstrual cycles during perimenopause, they begin to lose less iron than during their reproductive years. However, their needs still tend to be higher than those of men, as their iron stores may be gradually decreasing.

C. Adolescent girls

This is incorrect because adolescent girls have one of the highest iron requirements due to growth and the onset of menstruation. The RDA for iron in adolescent girls is about 15 mg per day to support increased blood volume, muscle growth, and menstruation.

D. Menopausal women

This is incorrect because menopausal women typically have iron needs similar to those of men. Since they no longer experience menstruation, their iron requirements decrease significantly, but they are still slightly higher than the needs of men in their age group. The RDA for iron in menopausal women is 8 mg per day, similar to men, but often slightly adjusted based on individual health factors.

Correct Answer:

B. Mechanical and chemical

Explanation of the Correct Answer:

The process of digestion involves both mechanical and chemical actions. Mechanical digestion refers to the physical breakdown of food into smaller pieces, such as chewing and the churning action of the stomach. Chemical digestion involves the breakdown of food by enzymes and acids, which chemically alter the food into smaller molecules that the body can absorb.

Why the Other Options Are Incorrect:

A. Chemical and electrical

This option is incorrect because while chemical processes are involved in digestion, electrical is not a primary action. Electrical activity, like nerve impulses, does play a role in controlling digestive processes, but it is not a main action in digestion itself.

C. Mechanical and thermal

Thermal digestion is not a term associated with the digestive process. Mechanical digestion refers to the physical breakdown of food, but thermal does not describe any part of digestion.

D. Thermal and chemical

While chemical digestion is correct, thermal is not related to digestion. Thermal typically refers to heat, which does not have a primary role in the breakdown of food in the digestive process.

Summary:

The process of digestion primarily involves mechanical and chemical actions. Mechanical digestion physically breaks down food, while chemical digestion uses enzymes and acids to chemically break down food into absorbable nutrients.

Correct Answer: D. First is false, second true

Explanation of the Correct Answer:

D is correct because the first statement about women practicing pica typically being from higher socioeconomic groups with more than a high school education is false. In fact, pica is more commonly observed in certain vulnerable populations, such as those from lower socioeconomic groups, or individuals with lower levels of education. Pica can also be seen more frequently in pregnant women and those with certain mental health conditions or nutritional deficiencies.

The second statement, however, is true. Pica is indeed an eating disorder that is characterized by the persistent ingestion of non-food substances, such as dirt, clay, chalk, or hair. It can have serious health consequences, including malnutrition or poisoning.

Why the Other Options are Incorrect:

A. Both are true

This is incorrect because the first statement about socioeconomic status and education level is false, making this option not correct.

B. Both are false

This is incorrect because the second statement about pica being an eating disorder that involves the ingestion of non-food substances is true.

C. First is true, second false

This is incorrect because the first statement about pica being more common in higher socioeconomic groups is false, and the second statement about the definition of pica is true.

Correct Answer: A. Increased urinary output

Explanation of the Correct Answer:

A is correct because increased urinary output is not a classic sign of fluid volume deficit (FVD). In fact, during FVD, the body typically attempts to conserve water, resulting in decreased urinary output, not increased. The kidneys retain as much fluid as possible to compensate for the deficit.

Why the Other Options are Incorrect:

B. Dry skin

This is incorrect because dry skin is a classic sign of fluid volume deficit. As the body loses fluids, it reduces blood flow to the skin, resulting in dryness and a lack of elasticity.

C. Decreased muscular function

This is incorrect because decreased muscular function is a common symptom of FVD. Dehydration can cause muscle weakness, cramping, and fatigue due to the lack of fluid needed for proper muscle function.

D. Fissures in a dry tongue

This is incorrect because fissures in a dry tongue are a typical sign of fluid volume deficit. Dehydration can lead to dryness in the mouth and tongue, causing cracks or fissures.

Correct Answer:

B. Vegan

Explanation of the Correct Answer:

Vegans are most at risk for nutrient deficiencies because they avoid all animal products, including dairy, eggs, and meat. This can lead to potential shortages of essential nutrients such as vitamin B12, iron, calcium, omega-3 fatty acids, vitamin D, and protein. These nutrients are often found in animal-based foods, and a vegan diet requires careful planning to ensure that adequate amounts of these nutrients are obtained through plant-based sources or supplements.

Why the Other Options Are Incorrect:

A. Semi-vegetarian

A semi-vegetarian typically follows a mostly plant-based diet but occasionally consumes small amounts of meat or fish. Since they still consume animal products, they are less likely to experience the nutrient deficiencies that vegans might face.

C. Lacto-ovovegetarian

Lacto-ovovegetarians consume both dairy products and eggs, which help provide essential nutrients like calcium, vitamin B12, and protein. This makes them less at risk for nutrient deficiencies compared to vegans.

D. Pollo-vegetarian

A pollo-vegetarian includes poultry in their diet but avoids red meat. The inclusion of poultry provides a source of important nutrients like protein, iron, and vitamin B12, making them less likely to have nutrient deficiencies compared to vegans.

Summary:

Vegans are most at risk for nutrient deficiencies because their diet excludes all animal products, which are key sources of several essential nutrients. Semi-vegetarians, lacto-ovovegetarians, and pollo-vegetarians are less at risk since they still consume some animal-based products.

Correct Answer: D. Fiber contributes to constipation

Explanation of the Correct Answer:

D is correct because fiber does not contribute to constipation; in fact, it helps to prevent constipation. Fiber, particularly soluble fiber, absorbs water and forms a gel-like substance, which softens stool and promotes regular bowel movements. Insoluble fiber adds bulk to the stool, helping it pass more easily through the intestines. Therefore, fiber is actually beneficial in preventing constipation, not causing it.

Why the Other Options are Incorrect:

A. Fiber increases stool bulk

This is correct because fiber, especially insoluble fiber, adds bulk to stool by absorbing water and helping to move waste through the digestive system more efficiently.

B. Fiber increases muscle tone of digestive muscles

This is correct because fiber promotes regular bowel movements, which can help stimulate the digestive muscles (peristalsis) to work more effectively, increasing their muscle tone and overall function.

C. Fiber slows starch hydrolysis

This is correct because soluble fiber can slow the breakdown of starches into simple sugars by forming a gel-like substance, which can help regulate blood sugar levels and prevent rapid spikes in glucose levels.