Ch. 18- Prep for Exam

Indicate the functions of cholesterol. Check all that apply.

-Precursor for some hormones -Precursor for bile salts -Structural component of cell membranes

Beta-carotene is a precursor for vitamin __________.

A

What is a complete protein?

A dietary protein that provides adequate amounts of all essential amino acids to maintain life and support growth

What structure regulates appetite?

Hypothalamus

Define the term gluconeogenesis.

Production of glucose from non-carbohydrates, like proteins and fats

What occurs during the series of reactions called beta oxidation?

Removal of two-carbon segments from fatty acids

Neuropeptide Y __________ appetite.

Stimulates

Indicate the vitamins that function as antioxidants. Check all that apply.

Vitamin A and E

What does body mass index (BMI) measure?

Weight relative to height

Indicate which of the following are complex carbohydrates (polysaccharides). (Check all that apply.)

-Glycogen -Starch -Cellulose

For each kilogram of body weight, an individual requires __________ of energy to maintain their basal metabolic rate.

1 calorie per hour

1. The inorganic portion of bone tissue consists of what two minerals? 2. Vitamin __________ functions in the absorption of minerals needed for bone formation. 3. In children, deficiency of this vitamin results in deformity of bones. What is this condition called?

1. Calcium and phosphorus 2. D 3. Rickets

Complete the sentences and place them in order to describe the process of protein metabolism.

1. Dietary proteins are digested to amino acids (the subunits of peptides, polypeptides, and proteins) by the digestive system. 2. Amino acids are absorbed into the blood and delivered to cells. Most amino acids are used by cells to form proteins, guided by DNA. 3. Amino acids can be used for energy, or to produce glucose or fat. First, however, the amino acid must undergo deamination, which is the removal of the nitrogen group. 4. The nitrogen groups removed from amino acids are converted to a molecule called urea by the cells of the liver. This waste molecule is then excreted in the urine.

Name the hormone that regulates sodium levels in the blood by altering kidney reabsorption of sodium.

Aldosterone

Name the body's main use for triglycerides.

As an energy source

The absorption of vitamin __________ from the small intestine requires intrinsic factor, produced by stomach cells.

B12

Complete the sentences describing how different nutrients can be used to produce ATP.

Carbohydrates can be used as an energy source. The monosaccharide that enters the cellular respiration pathway is glucose. Other monosaccharides in the diet are converted to this form by cells of the liver. In order to use proteins as an energy source, they must first be digested into amino acids. These digestion products then must undergo deamination, removing the -NH2 groups. The remaining parts of these molecules can enter various points of the respiratory pathway, resulting in the production of ATP. Triglycerides can be used as an energy source. They must first undergo the process of hydrolysis, producing glycerol and fatty acids. The fatty acids are further broken down into 2-carbon units by the process of beta oxidation. The 2-carbon units enter the respiratory pathway as acetyl CoA molecules.

Name the process that an amino acid must undergo in order for it to be used for fuel or to produce glucose.

Deanimation

Several vitamins have roles in keeping epithelial and connective tissues healthy. Their deficiency results in symptoms involving these tissues. Complete the sentences describing these vitamins.

Deficiency of vitamin C, needed for collagen production, leads to scurvy. This condition is associated with bleeding gums, painful joints, and slowed healing. Deficiency of vitamin A leads to night blindness due to its role in forming visual pigments. It also is associated with degeneration of epithelial tissues. A type of dermatitis called pellagra is due to deficiency of niacin. Gastrointestinal effects and mental disorders also can occur. Deficiency of another B vitamin called riboflavin is also associated with dermatitis.

Complete the sentences describing complete and incomplete proteins. Labels can be used more than once.

Dietary proteins that are complete proteins provide adequate amounts of all essential amino acids. Other proteins, classified as incomplete proteins, cannot support life, growth, and development because of a lack of an essential amino acid. If cells are missing a(n) essential amino acid, they are unable to produce any protein that incorporates that particular amino acid. Meats, dairy, and eggs contain complete protein. Plant-based foods (with the exception of soy) have inadequate quantities of at least one essential amino acid. Vegetarians, especially vegans, need to eat combinations of plant-based foods. By combining the incomplete proteins in plants, they should get all needed essential amino acids.

Isoleucine, leucine, and lysine are three examples of amino acids that the body can not make in sufficient quantity. How are these compounds classified?

Essential amino acids

Cholesterol, a type of lipid, is abundant in plant-based foods.

FALSE

The B vitamins and vitamin C are fat-soluble vitamins.

FALSE

What is the product of the process of lipogenesis?

Fat

What nutrient is absorbed along with other lipids, dissolves in lipids, and can lead to overdose with excess intake?

Fat-soluble vitamins

Which class of vitamin is more likely to be stored in the tissues of the body?

Fat-soluble vitamins

Why is dietary fiber beneficial to the diet?

Fiber provides "bulk" in intestines, allowing better movement of intestinal contents.

What is the product of the process of glycogenesis?

Glycogen

The fat-soluble vitamin __________ can be produced by intestinal bacteria.

K

Match the definition to the correct class of nutrients.

Minerals- inorganic elements needed for metabolism Vitamins- organic essential compounds needed in very small amounts; needed for normal metabolism

Name the B vitamin that can be made from the amino acid tryptophan.

Niacin

Someone consuming more protein than they are losing via excretion are in _______ nitrogen balance.Someone consuming less protein than they are losing via excretion are in ______ nitrogen balance.

Positive; negative

What types of fats are associated with increased risk of cardiovascular disease?

Saturated fats

Indicate which situations lead to primary malnutrition. Check all that apply.

-Lack of available food -Anorexia nervosa Malnutrition is defined as poor nutrition and includes both undernutrition and overnutrition. Primary malnutrition is due to diet alone. Secondary malnutrition occurs because of (secondary to) some other cause or condition.

1. Several B vitamins, including __________ and __________ are necessary to produce DNA. Due to their rapid production, RBCs are affected if these vitamins are deficient; anemia can develop. 2. Production of hemoglobin requires what mineral? 3. Long-term deficiency of __________ and/or __________ leads to pernicious anemia, a condition in which nerve damage has already occurred at the time the anemia becomes symptomatic. 4. Deficiency of __________ leads to megaloblastic anemia, in which abnormal RBCs are very large (megalo-) and nucleated. 5. Deficiency of __________ leads to an anemia in which the RBCs are very pale, due to reduced quantity of hemoglobin.

1. Folic acid; vitamin B12 2. Iron 3. Vitamin B12; cobalt 4. Folic acid 5. Iron

Complete the sentences describing the food sources for the various nutrients. Then place the sentences in order reflecting the percent of daily intake needed from each source (from greatest to least).

1. Plant-based foods such as fruits, vegetables, and grains are good sources of carbohydrates. 2. Oils, beef, whole milk, and many types of junk food provide a source of lipids. 3. Meat and dairy products as well as legumes and nuts provide protein.

1. Cramps and convulsions result from hyperexcitability of neural and muscular tissue. This can be caused by a deficiency in what mineral? 2. Tetany (sustained contractions) can result from deficiency of __________. This mineral also is needed for bone formation. 3. Deficiency in __________ results in muscular weakness due to hyperpolarization of the cell membranes.

1. Sodium 2. Calcium 3. Potassium

Energy Balance

A person in positive energy balance will gain weight. A person in energy balance will maintain weight. A person in negative energy balance will lose weight

The labels describe the eating disorders anorexia nervosa and bulmia. Place the labels into the appropriate box. Labels can be used more than once.

ANOREXIA NERVOSA -Self induced starvation -Eating involves rituals -Extreme weight loss -Vomiting and use of laxatives BULEMIA -Vomiting and use of laxatives -Typically of normal weight -Binge and purge -May eat large quantities of food at one time -Tooth decay; esophageal ulcerations

Complete the sentences describing an adequate diet.

An adequate diet supplies enough calories for energy, and essential nutrients for maintenance, healing, and growth. Actual amounts of nutrients and energy needed varies widely, depending on gender, age, growth rate, and other factors. Recommended Daily Allowances (RDAs) are amounts of nutrients, depending upon age and gender, that will avoid deficiencies or excess conditions. Another type of guideline for determining an adequate diet are those established by the USDA. Models called food pyramids were used in the past. The current model is called My Plate, and is intended to provide a visual reminder of how much of each type of food should be consumed daily.

The vitamin __________ is a coenzyme for reactions involving nitrogen-containing compounds, including proteins and amino acids. Therefore, the dietary need for this vitamin depends on protein intake.

B6

Parathyroid hormone stimulates the production of the active form of vitamin __________, which then increases calcium absorption by the digestive system.

D

Within the skin, ultraviolet (UV) light striking a provitamin derived from cholesterol results in conversion of the provitamin to vitamin __________.

D

With aging, the number of calories needed in the diet gradually increases.

FALSE

Complete the sentences describing fats in the diet.

Fats should account for 30% or less of the calories consumed daily, with saturated fats accounting for no more than 10% of the total fat intake. Saturated fats tends to increase blood cholesterol levels, are solid at room temperature, and are found mostly in meat and dairy products. Unsaturated fats tends to lower blood cholesterol levels and are found mostly in plant sources. Dietary cholesterol is found only in foods from animal sources, including meat, milk, eggs, and butter.

After absorption from the digestive tract, all monosaccharides are converted by liver enzymes to what compound?

Glucose

Match each description with the correct type of lipoprotein.

High concentration of protein; low concentration of lipid- High-density lipoproteins (HDLs) High concentration of cholesterol- Low-density lipoproteins (LDLs) High concentration of triglycerides- Very-low-density lipoproteins (VLDLs)

Complete the sentences describing energy balance and weight.

If caloric intake equals caloric expenditure, an individual is in energy balance. This person will have a steady body weight. When calories consumed are greater than the amount of calories burned, a person will be in positive energy balance. Excess energy will be stored as fat. A pound of adipose tissue stores 3500 calories. This person will gain weight. In order to create a negative energy balance, energy expenditure needs to be greater than the amount of calories consumed. Increased physical activity can help achieve this balance, allowing the person to lose weight.

Complete the sentences regarding protein and its turnover.

In the body, proteins are continually being made and broken down. Ideally, the amount of protein made equals the amount of protein broken down, a situation called nitrogen balance. Because a high percentage of the body's nitrogen is in protein, nitrogen balance gives an idea of protein balance as well. Proteins are being produced using the guidance of the nucleic acids, which contain genetic information. For proteins to be assembled, all the necessary amino acids must be available. If any essential amino acid (those the body cannot make) is lacking, proteins that require them for assembly will not be produced. If protein intake is inadequate, the body will undergo wasting as the structural proteins, particularly of muscle, are broken down but not replaced.

Which hormone, if it were to be used clinically, could help in weight loss?

Leptin

The hormone called ______ suppresses appetite. It does so by inhibiting the release of ______, a neurotransmitter released from the hypothalamus. This compound ______ eating.

Leptin; neuropeptide Y; stimulates

In comparing the classes of macronutrients, name the class that provides the most energy per gram.

Lipids

Substances called __________ consist of a surface layer of phospholipid, cholesterol, and protein that surrounds a core consisting of triglycerides and other lipid-soluble compounds.

Lipoproteins

Carbohydrates, lipids, and proteins are __________ that provide energy and are required in large amounts. Vitamins and minerals are __________ that do not provide energy and are required in smaller amounts.

Macronutrients; micronutrients

Complete the sentences defining nutrition and the classification of nutrients.

Nutrition is the study of compounds called nutrients, their chemistry, and how they are used in the body. A nutrient is any element or compound necessary for or contributing to an organism's metabolism, growth, or other functions. The six classes of compounds are divided into those needed in greater quantities, called macronutrients, and those needed in very small quantities, called micronutrients. Three classes of nutrients, the carbohydrates, proteins, and fats, provide the body with energy (calories). Other nutrients support metabolic processes in the body and include the vitamins, minerals, and water. Some nutrients are classified as essential nutrients because they cannot be synthesized in the body and must be obtained from a food source.

Match each organic molecule with the mineral that forms part of its structure.

Phosphorus- ATP Sulfur- insulin, biotin, thiamine Iodine- thyroid hormone Cobalt- vitamin B12 Iron- hemoglobin

Of the six classes of nutrients, name the type of nutrient that provides nitrogen for the body.

Protein

Name the minerals that are important electrolytes for muscle and nerve function. Check all that apply.

Sodium, potassium, and calcium

Complete the sentences, then put the steps of lipid metabolism in order.

Stored triglycerides are hydrolyzed to form glycerol and fatty acids. Glycerol can (1) be converted to glucose, (2) be used to re-form triglycerides, or (3) enter the cellular respiration pathway to produce ATP. Fatty acids go through the process of beta-oxidation to form two-carbon molecules that can be converted to acetyl CoA. Acetyl-CoA enters the citric acid cycle of the cellular respiration pathway and ATP is produced.

Why are some nutrients classified as essential nutrients?

The body cannot produce them in adequate amounts, so it is essential that they be in the diet.

Medical and socioeconomic conditions of many elderly leads to __________.

Undernutrition

Drop each vitamin into the box describing its major function(s). Boxes may end up with one item, more than one item, or none.

Vitamin K- affect blood clotting Vitamin A and E- acts as antioxidants Vitamin D- needed for healthy bones