DH 209 Nutrition Exam

Correct Answer:

B. Additional calories are needed the first and second trimester

Explanation of the Correct Answer:

The statement that additional calories are needed during the first and second trimester is incorrect. While it is true that pregnant women need additional calories, this increase typically occurs during the second and third trimesters, not the first. During the first trimester, most women do not need a significant increase in caloric intake. Instead, the focus should be on ensuring that the diet provides sufficient nutrients for the developing fetus.

Why the Other Options Are Correct:

A. Additional 21 grams of protein needed each day

This statement is correct. During pregnancy, protein needs increase to support the growth and development of the fetus. It is recommended that pregnant women consume an additional 21 grams of protein daily to meet these needs.

C. Avoid consuming old fish that may contain unsafe levels of mercury

This statement is also correct. Pregnant women are advised to avoid consuming fish that may contain high levels of mercury, as mercury can negatively affect fetal development, particularly the development of the brain and nervous system.

D. Weight gain of 25-35 pounds

This statement is correct as well. A weight gain of 25 to 35 pounds is generally recommended for women with a normal pre-pregnancy weight. This range can vary depending on the individual’s health and pre-pregnancy weight.

Summary:

Additional calories are typically needed during the second and third trimesters of pregnancy, not the first. Pregnant women should aim for an additional 21 grams of protein per day, avoid fish with high mercury levels, and gain a healthy amount of weight (25-35 pounds) during pregnancy.

Correct Answer:

B. Cheese cubes

Explanation of the Correct Answer:

Cheese cubes are an excellent choice to reduce the risk of dental caries. Cheese contains calcium, phosphates, and casein, which help to neutralize acids in the mouth and remineralize tooth enamel. Cheese also stimulates saliva production, which helps to wash away food particles and neutralize harmful acids that can lead to tooth decay. Additionally, cheese has a low sugar content and does not contribute to plaque formation, making it a caries-preventive snack.

Why the Other Options Are Incorrect:

A. Caramel candy:

Caramel candy is high in sugar and sticky, which means it can cling to the teeth for longer periods of time, providing a food source for harmful bacteria in the mouth. These bacteria produce acids that lead to the demineralization of enamel and increase the risk of dental caries.

C. Peanut butter and crackers:

While peanut butter is a relatively healthy snack with healthy fats and protein, crackers are typically high in refined carbohydrates, which can break down into sugars in the mouth. These sugars can contribute to plaque formation and cavities. Also, peanut butter, while nutrient-dense, is sticky and can adhere to the teeth, prolonging the sugar's contact with the enamel, though it's a better choice than highly sugary snacks.

D. Raisins:

Raisins, although they are a natural source of fiber and nutrients, are dried fruit and contain high amounts of natural sugars. They are also sticky, meaning they can adhere to the teeth for longer periods, potentially increasing the risk of tooth decay. The sugar content in raisins can feed bacteria in the mouth, leading to acid production and increased risk of cavities.

Correct Answer:

C. Taste papillae appear on the tongue as large red spots or small bumps.

Explanation of the Correct Answer:

While it's true that taste papillae are small bumps on the tongue, they do not typically appear as large red spots. The description of taste papillae as large red spots is inaccurate because, in reality, the papillae themselves (including fungiform, circumvallate, and foliate papillae) are small and somewhat raised bumps. They are not necessarily red in color, although they may appear slightly more prominent or reddish due to the blood vessels in the underlying tissue. The larger, red spots on the tongue are more likely to be related to certain conditions like infections or inflammation rather than normal papillae.

Why the Other Options Are Correct Descriptions of Taste Papillae:

A. Taste papillae replace themselves every 3 to 10 days.

This statement is true. The taste buds on the papillae regenerate fairly rapidly, with a typical turnover time of 3 to 10 days, although this can slow with age or certain health conditions. This regeneration allows us to maintain the ability to taste over time.

B. Filiform papillae provide no sense of taste.

This is true. The filiform papillae, which are the most numerous type of papillae on the tongue, do not have taste buds and are therefore not involved in taste sensation. Instead, they provide texture to help manipulate food in the mouth and assist with the sense of touch. They are responsible for the rough texture on the surface of the tongue.

D. Taste papillae are most numerous on the dorsal epithelium of the tongue.

This is true. The dorsal epithelium refers to the top surface of the tongue, where the taste papillae are most concentrated. The fungiform and circumvallate papillae (both containing taste buds) are most numerous here, particularly near the tip and back of the tongue.

Correct Answer:

B. First is true, second false

Explanation of the Correct Answer:

Vitamin C is indeed essential for collagen formation, which is necessary for the strength and integrity of tissues and capillaries. It plays a crucial role in wound healing and maintaining the structure of connective tissues. However, the second statement is false. Vitamin C is not known as the "sunshine vitamin"; that term refers to Vitamin D. Vitamin D is synthesized in the skin through exposure to sunlight, hence its nickname.

Why the Other Options Are Incorrect:

A. First is false, second true

This option is incorrect because the first statement about Vitamin C's role in collagen formation is true, but the second statement about Vitamin C being the "sunshine vitamin" is false; it is Vitamin D that holds that title.

C. Both are false

This option is incorrect because the first statement about Vitamin C's role is accurate, and only the second statement is false.

D. Both are true

This option is incorrect because the first statement about Vitamin C is true, but the second statement regarding Vitamin C being the "sunshine vitamin" is false.

Summary:

Vitamin C is crucial for collagen formation, tissue strengthening, and capillary integrity. However, Vitamin C is not the "sunshine vitamin"; that term refers to Vitamin D.

Correct Answer:

A. First is true, second false

Explanation of the Correct Answer:

It is true that rates of food insecurity are higher for households with children headed by a single father compared to the national average. Food insecurity refers to the lack of access to enough food due to limited financial resources, not a lack of knowledge of food preparation. The second statement is false because food insecurity is not defined by a lack of knowledge on food preparation but rather by the inability to secure enough nutritious food.

Why the Other Options Are Incorrect:

B. Both are false

This option is incorrect because the first statement is true: households headed by a single father indeed experience higher rates of food insecurity. The second statement is false, as food insecurity is related to access, not knowledge of food preparation.

C. First is false, second true

This option is incorrect because the first statement is true, and the second statement is false. Food insecurity is not about food preparation knowledge.

D. Both are true

This option is incorrect because the second statement is false. Food insecurity refers to the inability to access sufficient food, not a lack of food preparation knowledge.

Summary:

Rates of food insecurity are higher for households with children headed by a single father, but food insecurity itself is not related to a lack of knowledge about food preparation. It is about having limited access to enough food.

Correct Answer:

C. It is rare for newborns to receive a single dose of a vitamin K intramuscularly immediately after birth to prevent hemorrhage.

Explanation of the Correct Answer:

This statement is false. In fact, it is standard practice for newborns to receive a single dose of vitamin K intramuscularly immediately after birth to prevent hemorrhagic disease of the newborn (HDN), a condition that can cause serious bleeding due to insufficient vitamin K. Newborns have low vitamin K levels at birth, and vitamin K plays a crucial role in the production of clotting factors. This injection is a routine preventive measure in many countries and is not considered rare.

Why the Other Options Are Correct:

A. It's important in blood clot formation:

This is true. Vitamin K is essential for the synthesis of clotting factors (such as prothrombin) in the liver, which are crucial for blood coagulation. Without sufficient vitamin K, blood clotting would be impaired.

B. No UL has been established:

This is true. As of now, the Tolerable Upper Intake Level (UL) for vitamin K has not been established because there is no known risk of toxicity from excessive intake, especially from food sources. However, excessive intake from supplements may interact with blood-thinning medications.

D. It can be produced in the gut:

This is true. Vitamin K is produced by bacteria in the intestines, and the body absorbs a portion of it from there. This form of vitamin K is called menaquinone (vitamin K2), and it supplements the intake of vitamin K from food sources.

E. It's also known as Quinone:

This is true. Vitamin K is a group of fat-soluble vitamins that share a quinone structure, which is a chemical component that plays a role in its biological activity, including its role in blood clotting.

Correct Answer: A. Calcium within saliva increases the risk for caries.

Explanation of the Correct Answer:

A is correct because calcium within saliva does not increase the risk for caries. In fact, calcium in saliva actually plays a protective role against dental caries. It helps to mineralize demineralized enamel, a process that can help repair the tooth enamel that has been softened by acidic conditions in the mouth. Calcium in saliva can help reduce the risk of caries, not increase it.

Why the Other Options are Incorrect:

B. Calcium in saliva provides a buffering action

This is incorrect because calcium does provide a buffering action in the mouth. It helps to neutralize acids and maintain a balanced pH, which reduces the demineralization of tooth enamel and helps to protect against caries

C. Saliva is a source of calcium to mineralize demineralized enamel.

This is incorrect because saliva does indeed act as a source of calcium to help remineralize demineralized enamel. When enamel starts to break down due to acidic exposure, calcium from saliva can help restore the enamel and repair early stages of decay.

D. Saliva is supersaturated with calcium

This is incorrect because saliva is supersaturated with calcium, meaning it contains more calcium than it can hold in a stable form, which makes it effective in preventing demineralization of teeth and promoting remineralization. This helps to protect teeth from the harmful effects of acids and caries.

Correct Answer:

D. Both statements are true.

Explanation of the Correct Answer:

The first statement is true:

The stomach acts as a reservoir that holds food after it enters. The average meal typically stays in the stomach for about 6 to 8 hours before being passed into the small intestine. This time can vary depending on factors such as meal size, composition, and individual factors (e.g., gastric motility). The stomach's role is to store food, start the digestion process, and gradually release food into the small intestine.

The second statement is true:

The rate at which different types of food pass through the stomach varies. In general, the rate of gastric emptying is as follows:

Liquids: Liquids pass through the stomach the fastest, as they are easily absorbed and do not need as much time for digestion or breakdown.

Carbohydrates: Simple carbohydrates typically follow, as they are relatively easy to break down and digest.

Proteins: Proteins take longer to digest and therefore move through the stomach at a slower rate than carbohydrates.

Fats: Fats take the longest to digest, as they require more time for enzymatic breakdown and absorption, and thus pass through the stomach last.

Why the Other Options Are Incorrect:

A. Both statements are false.

This option is incorrect because both statements are true. The stomach functions as a reservoir, and the passage rates for different food types follow the described order (liquids, carbohydrates, proteins, and fats).

B. The first statement is true; the second is false.

This option is incorrect because the second statement is actually true. The passage rates of liquids, carbohydrates, proteins, and fats are well-documented, and they follow the correct order as described.

C. The first statement is false; the second is true.

This option is incorrect because the first statement about the stomach acting as a reservoir to hold food for 6 to 8 hours is accurate. Therefore, both statements are true.

Correct Answer:

C. Saliva extracts calcium and phosphate from demineralized tooth surfaces.

Explanation of the Correct Answer:

While saliva plays a key role in maintaining oral health, it does not directly extract calcium and phosphate from demineralized tooth surfaces. Remineralization is a process where saliva provides calcium and phosphate ions to help repair enamel damage. However, saliva does not extract these minerals from the enamel. Instead, saliva helps remineralize teeth by depositing calcium and phosphate ions onto demineralized enamel, promoting repair, rather than extracting them.

Why the Other Options Are Correct in Relation to the Functions of Saliva:

A. Saliva lubricates oral tissues.

Saliva provides moisture and lubrication for the oral tissues, which helps with swallowing and prevents the mouth and throat from becoming dry. It also helps in speech and the smooth movement of food through the mouth.

B. Saliva buffers bacterial acids.

Saliva plays a critical role in neutralizing acids in the mouth, especially those produced by bacteria after consuming food. The buffering action of saliva helps maintain a neutral pH in the mouth, which helps prevent tooth decay and protects soft tissues from damage.

D. Saliva is essential to gustatory sensations.

Saliva is essential for the taste sensation because it dissolves food particles, allowing the taste receptors on the tongue to detect different tastes (sweet, sour, salty, bitter, and umami). Without saliva, it would be difficult to taste food effectively.

E. Saliva provides antibacterial action.

Saliva contains enzymes such as lysozyme and lactoferrin, which have antibacterial properties. These enzymes help reduce the growth of harmful bacteria in the mouth and protect against infections by controlling bacterial growth.