Principles of Dietetics

Question 1

_______ is a nutrient needed in large quantities, and _______ is a nutrient needed in smaller quantities

Answer 1

Macronutrient is a nutrient needed by the body in larger quantities and usually measured in grams. Examples include carbohydrates, proteins, and fats

Micronutrient is a nutrient needed by the body in smaller quantities. These are usually measured in milligrams (mg) or micrograms (mcg). Examples include vitamins and minerals

Question 2

Distinguish between organic and inorganic molecules

Answer 2

Organic: Chemically speaking, this refers to molecules which contain carbon atoms. Glucose is an example of an organic molecule with the chemical structure of C6 H12 O6

Inorganic: This refers to molecules which do not contain a carbon atom. Water is an example of an inorganic molecule with the chemical structure of H2O

Question 3

Define macronutrient and micronutrient and provide examples of each

Answer 3

Macronutrient: Nutrient needed by the body in larger quantities and usually measured in grams. Examples include carbohydrates, proteins, and fats

Micronutrient: Nutrient needed by the body in smaller quantities. These are usually measured in milligrams (mg) or micrograms (mcg). Examples include vitamins and minerals

Question 4

Define nutrigenomics

Answer 4

Nutrigenomics is the study of nutrient-gene reactions. This looks at how food affects a person’s genes as well as how a person’s genes affect the way the body responds to food. This is an important field with regards to the prevention or treatment of disease

Question 5

H2O is the chemical structure for a molecule of water. Is this an organic or an inorganic molecule?

Answer 5

H2O, a molecule of water, is an inorganic molecule because of the lack of a carbon atom. Chemically speaking, an organic molecule is one which contains at least one carbon atom. Glucose, with the chemical structure of C6 H12 O6, is an example of an organic molecule

Question 6

The study of how food affects a person’s genes is known as what?

Answer 6

Nutrigenomics is the study of nutrient-gene reactions. This looks at how food affects a person’s genes as well as how a person’s genes affect the way the body responds to food. This is an important field with regards to the prevention or treatment of disease

Question 7

Rate the following as either an essential or a non-essential nutrient:
* Vitamin B12
* Vitamin K
* Vitamin D
* Vitamin C
* Vitamin A
* Biotin

Answer 7

An essential nutrient is one which must be obtained by food. Of the list in the question, the essential nutrients include vitamins A, C, and B12

A non-essential nutrient can be made in the body. Biotin can be produced by GI bacteria. Vitamin D can be synthesized by sunlight and cholesterol. Vitamin K can be produced by intestinal bacteria

Question 8

Distinguish between essential, non-essential, and conditionally-essential nutrients

Answer 8

Essential: Nutrient that must be obtained from food because the body cannot manufacture sufficient quantities or any at all. Many amino acids are considered essential

Non-essential: Nutrient which can be made by the body or obtained by sources other than foods and beverages. Vitamin D is an example of a non-essential nutrient. With the help of sunlight and cholesterol in the body, vitamin D can be synthesized

Conditionally-essential: Under normal circumstances, the body can produce adequate supplies of the nutrient. However, during times of stress or illness, the nutrient cannot be made to meet demands, and therefore becomes essential. The amino acids arginine, glutamine, cysteine, tyrosine, glycine, proline, and serine are examples of conditionally-essential nutrients

Question 9

List some food sources of prebiotics

Answer 9

Prebiotics are a special plant fiber that help healthy bacteria in the gut grow. Prebiotics can be found in foods, such as apples, bananas, berries, artichokes, asparagus, garlic, green vegetables, onions, tomatoes, legumes, soybeans, wheat, oats, and flaxseed

Question 10

Compare gluconeogenesis to glycogenolysis

Answer 10

Gluconeogenesis is the formation of glucose from a non-carbohydrate source, such as pyruvate, lactate, glycerol, glucogenic amino acids, and some fatty acids. This process primarily takes place in the liver, and to a much smaller extent in the cortex of the kidneys. The purpose of this process is to maintain blood glucose levels

Glycogenolysis is the process of breaking down glycogen to glucose. This process if increased in times of starvation, extreme exercise, and in high adrenaline situations

Question 11

Fruits, oats, barley, and legumes are food sources of which type of fiber?

Answer 11

Soluble fibers are those which dissolve in water. These are usually found in fruits, oats, barley, and legumes. Some important features of soluble fibers include:
* Delays gastric emptying and transit of chyme through the intestines
* Delays glucose absorption
* Can help lower serum cholesterol

Question 12

Ketone bodies are produced when _____ are broken down

Answer 12

Fats

Carbohydrates are the preferred fuel source of the body. When there is a lack of available carbohydrates, fat and protein will be broken down. The byproduct of fat metabolism is known as ketones, or ketone bodies

Question 13

Wheat grains, bran rice, cabbage, Brussels sprouts, nuts, and seeds are food sources of which type of fiber?

Answer 13

Insoluble fiber does not dissolve in water. Some important features of this type of fiber include:
* Accelerates the transit of chyme through the intestine
* Increases fecal weight
* Slows starch breakdown and delays glucose absorption into the blood

Question 14

Compare the different classifications of carbohydrates: monosaccharides, disaccharides, and polysaccharides

Answer 14

Monosaccharides: Made up of only one molecule of sugar. Also referred to as a “simple sugar”. Examples include glucose, fructose, and galactose

Disaccharides: Made up of two monosaccharides chemically joined together. Examples include sucrose (glucose + fructose), lactose (glucose + galactose), and maltose (glucose + glucose)

Polysaccharides: Made up of several to many monosaccharides chemically joined together. Also referred to as a “complex carbohydrate”. Polysaccharides may be digestible or non-digestible (dietary fiber). Examples include starch, dextrin, glycogen, cellulose, hemicellulose, inulin, pectin, amylose, and amylopectin

Question 15

Does insoluble fiber accelerate or delay the transit of chyme through the intestines?

Answer 15

Accelerate

Insoluble fiber accelerates the transit of chyme through the intestines. Contrary, soluble fiber delays gastric emptying and the transit of chyme through the intestines

Question 16

Provide some characteristics of glycogen

Answer 16

Glycogen:
* Branched polysaccharide
* Storage form of carbohydrates in mammals
* Stored in the liver and muscles
* The average human can store approximately 1,500 to 2,000 calories from glycogen

Question 17

______ are a special class of plant fibers which help healthy bacteria in the gut grow

Answer 17

Prebiotics are a special plant fiber that help healthy bacteria in the gut grow. Prebiotics can be found in foods, such as apples, bananas, berries, artichokes, asparagus, garlic, green vegetables, onions, tomatoes, legumes, soybeans, wheat, oats, and flaxseed

Prebiotics are important for the following reasons:
* Feeds the “good” bacteria in the gut, aiding in a healthy bowel system
* Keeps the cells that line the gut healthy
* Improves bouts of diarrhea, such as when caused by antibiotic treatment
* Helps absorb calcium
* Helps to avoid blood sugar spikes
* Improves the immune system

Question 18

Classify each of the following as either a monosaccharide, a disaccharide, or a polysaccharide:
* Starch
* Pectin
* Maltose
* Fructose
* Lactose

Answer 18

Monosaccharides: Made up of only one molecule of sugar. Also referred to as a “simple sugar”. Examples include glucose, fructose, and galactose

Disaccharides: Made up of two monosaccharides chemically joined together. Examples include sucrose (glucose + fructose), lactose (glucose + galactose), and maltose (glucose + glucose)

Polysaccharides: Made up of several to many monosaccharides chemically joined together. Also referred to as a “complex carbohydrate”. Polysaccharides may be digestible or non-digestible (dietary fiber). Examples include starch, dextrin, glycogen, cellulose, hemicellulose, inulin, pectin, amylose, and amylopectin

Question 19

The byproduct of fat metabolism is known as what?

Answer 19

Ketones, or ketone bodies, may be produced when fat is broken down in the body. This may occur when there is a lack of available carbohydrates, possibly during a period of starvation or extreme dieting. The brain prefers glucose as a source of energy but will utilize ketones as an energy source if necessary

Question 20

______ is a process in the body where glycogen is broken down to glucose

Answer 20

Glycogenolysis is the process of breaking down glycogen to glucose. This process if increased in times of starvation, extreme exercise, and in high adrenaline situations

Question 21

Distinguish between glycogen and starches

Answer 21

Glycogen is a branched polysaccharide and is the storage form of carbohydrates in mammals. It is stored in the liver and muscles of mammals. The average human can store approximately 1,500 to 2,000 calories from glycogen

Starches are the storage form of carbohydrates of plants

Question 22

What are some important features of soluble fibers?

Answer 22

Soluble fibers are those which dissolve in water. These are usually found in fruits, oats, barley, and legumes. Some important features of soluble fibers include:
* Delays gastric emptying and transit of chyme through the intestines
* Delays glucose absorption
* Can help lower serum cholesterol

Question 23

A baby is born at 36 weeks. She is now 3 months old. What is her corrected age?

Answer 23

2 months

First find the number of weeks preterm the baby was at birth:
40 weeks for full term - 36 weeks actual gestation = 4 weeks, or one month preterm

Next find the corrected age:
3 months chronological age - 1 month preterm = 2 months corrected age

Question 24

Compare catch-up growth to lag-down growth

Answer 24

Catch-up growth: Infants born at or below the 10th percentile for length may not reach their genetically growth pattern until 1 year of age

Lag-down growth: Infants who are larger at birth and are genetically determined to be smaller, grow at a slower rate and reach their appropriate growth channel around 13 months

Question 25

Compare the following birth weights:
* Normal weight
* Low birth weight
* Very-low birth weight

Answer 25

Normal weight: 5.5 to 8.5 pounds

Low birth weight: Less than 5 pounds, 8 ounces

Very-low birth weight: Less than 3 pounds, 4 ounces