FCS 331 - Test 2

*Sherita ate some whole-wheat crackers with grape jelly for a snack. As this snack passed through her digestive tract, discuss what happened to the starch, sucrose, and fiber in the food.

The small intestine is the main site for carbohydrate digestion and absorption, but a minor amount of starch digestion begins in the mouth, as salivary amylase converts some of the oat starch molecules into maltose. Starch digestion, however, stops soon after the food enters the acidic environment of the stomach. The fiber in the oats slows the rate at which chyme empties from the stomach, and this delay promotes fullness and satiety (the feeling that one has eaten enough).

*Explain the function of an emulsifier in food preparation and manufacturing.

An emulsifier is a substance that keeps water-soluble and water-insoluble compounds mixed together so in foods it keeps oily and watery ingredients from separating during storage

*What is gluten?

type of protein found in many grains; provides texture and shape to baked products

*List at least two strategies for reducing trans fat intake.

eating fewer solid fats, especially foods made with partially hydrogenated oils, such as stick margarine.

*What happens to a fatty acid during beta-oxidation?

fatty acid molecules are cleaved into two-carbon segments that are converted into acetyl CoA

*List four kinds of grains that contain gluten and four that are gluten-free.

g= Wheat, Wheat-enriched flour, Durum flour, Graham flour g-f = rice flour, potato starch flour, or soy flour, or buckwheat

*Explain why ketoacidosis can occur under certain conditions.

glucose cannot enter cells and be converted to pyruvate; high concentrations of acetoacetate and beta-hydroxybutyrate in the bloodstream lower the blood's pH and cause ketoacidosis;

*What are the components of a phospholipid?

glycerol backbone, a phosphorus (P), a nitrogen (N), and they have a hydrophilic and hydrophobic portion

*Name the monosaccharides that comprise each molecule of maltose, lactose, and sucrose.

maltose = glucose x2 lactose = glucose & galactose sucrose = glucose & fructose

*What is the primary advantage of aerobic metabolism over anaerobic metabolism?

more energy is made

*Identify at least three common food allergens.

peanuts, tree nuts, shellfish, milk, fish, wheat, soybeans, eggs

*Identify the type of bond that links amino acids in a protein.

peptide bond

*What happens in the catabolism of glucose under anaerobic conditions?

pyruvate is converted to lactic acid

*List five rich food sources of omega-3 fatty acids.

salmon, shrimp, tuna, canola oil, walnuts

*Identify at least two foods that are rich sources of (a) saturated fat, (b) monounsaturated fat, and (c) polyunsaturated fat.

saturated fat - coconut oil, butter fat, monounsaturated fat - olive oil, canola oil, polyunsaturated fat - Soybean oil, Garpeseed oil

*Explain the ways in which apple slices or whole-grain crackers that are topped with a tablespoon of peanut butter provide a more nutritious snack than a 1-½-ounce milk chocolate bar.

soluble fiber, protein, carbs from whole wheat?

*List potential health benefits of vegetarian diets.

tend to have a lower risk of obesity, type 2 diabetes, hypertension, and certain cancers

*What do plants need to make carbohydrates?

the sun's energy

*List the three major classes of lipids.

triglycerides, phospholipids, sterols

*What is reactive hypoglycemia and how can it be treated?

-Reactive hypoglycemia, also called postprandial hypoglycemia, is low blood glucose that occurs within 4 hours of eating. -avoid eating large amounts of sugary foods and eat smaller and eat more frequent meals that contain a mixture of macronutrients

*What are the signs and symptoms of type 1 and type 2 diabetes?

-Regardless of the type of diabetes, the primary sign of the disease is hyperglycemia, abnormally elevated blood glucose levels. -excessive thirst, excessive urination, and weight loss

*A healthy young woman weighs 136 pounds. Calculate her RDA for protein.

48

Blood Glucose Level (Fasting) _____-99 mg/dL = Normal 100-_____ mg/dL = Pre-diabetes _____ mg/dL or more = Diabetes

70, 125, 126

*What conditions stimulate insulin secretion? What conditions stimulate glucagon secretion?

After a carbohydrate-containing meal, the beta cells detect the rise in blood glucose levels (absorptive state) and secrete insulin. intense exercise, extreme stress, or starvation

* The monosaccharide is the simple sugar that is the basic molecule of carbohydrates. ___________ - Monosaccharide that is a primary fuel for muscles and other cells; "dextrose" or "blood sugar" __________ - Monosaccharide in fruits, honey, and certain vegetables; "levulose" or "fruit sugar" ___________ - Monosaccharide that is a component of lactose

Glucose, Fructose, Galactose

*What process must an amino acid undergo before it can be used for energy?

Before an amino acid can be used for ATP production, the nitrogen group must be removed by deamination or transamination

____________ are a class of nutrients that is a major source of energy for the body and is classified as simple and complex. Plants are rich sources of this.

Carbohydrates

*Does drinking sugar-sweetened soda contribute to obesity? Explain.

Findings from some scientific studies suggest that people who drink regular soft drinks do not reduce their energy intake from solid food accordingly.55 The reasons are unclear, but the fructose in these beverages may not reduce the urge to eat as does solid food. As a result, consumers of regular soft drinks ("liquid candy") are likely to overeat and have excessive energy intakes that contribute to weight gain. By contributing to unwanted weight gain, consumption of regular soft drinks may increase the risk of type 2 diabetes.

*According to the Dietary Guidelines, how much saturated fat, cholesterol, and trans fat should an adult consume?

Saturated fat - Less than 10% of total calories, Cholesterol - As little as possible while consuming a healthy diet, Trans fat - Keep intake as low as possible

*Distinguish between glycogen and starch, including similarities and differences.

Similarities - both are polysaccharides that contain hundreds of glucose molecules bound together into large, chainlike structures Differences - Starch is composed of amylose, a linear chain of glucose molecules, and amylopectin, a branched chain of glucose molecules; The chains of glycogen are more highly branched than those of starch (I need to finish this question)

*Identify at least two food sources of soluble fiber and two sources of insoluble fiber.

Soluble: Apples, bananas, citrus fruits, carrots, oats, barley, psyllium seeds, beans, and thickeners added to foods Insoluble: All plants, especially whole wheat, rye, brown rice, vegetables, whole grains, wheat bran

*Identify the consequences of untreated gestational diabetes.

-the fetus gains weight rapidly and can be abnormally heavy at birth, giving birth to such a large infant is risky for the mother as well as the infant, because it may prolong the birth process and cause the baby to be injured during delivery -more likely to have miscarriages, have a stillbirth, and premature labor -more likely to give birth to babies who have difficulty controlling their own blood glucose levels than mothers who do not have diabetes or develop the condition during pregnancy

*a healthy adult's RDA for protein is ___g/kg of body weight

0.8

*Hien is 24 years old and consumes approximately 3200 kcal per day. Calculate the range of calories he needs from protein, based on the AMDR for adult protein intake.

10 - 35% = 320 - 1120

*According to the Dietary Guidelines, people should limit their added sugar intake to less than ____% of total calories.

10%

*Recommended limit of added sugars (from 2015-2020 Dietary Guidelines)

10%

*"One CHO" = ___ grams of CHO*

15

*Calculate how many grams of total fat, saturated fat, linoleic acid, and alpha-linolenic acid an adult should consume who is eating 2300 kcal daily.

20 to 35% so 805 to 460kcal

*What percentage of total energy intake does fat contribute in the "average" American's diet?

20-35%

*How many carbons are needed to make glucose?

3

*In a typical triglyceride, how many atoms can become part of glucose?

3

*What structural characteristic distinguishes a trans fatty acid from a cis fatty acid?

A cis fatty acid has the two carbon atoms that are connected by a double bond, each having a hydrogen atom on the same side of the hydrocarbon chain. Trans fats have at least one trans double bond in their chemical structure and the hydrogen atoms of the double-bonded carbons within the hydrocarbon chain are on opposite sides of the chain.

*Explain the difference between essential, conditionally essential, and nonessential amino acids.

A healthy human body can make 11 of the 20 amino acids. These compounds are the nonessential amino acids. The remaining nine amino acids are essential amino acids that must be supplied by foods, because the body cannot synthesize them or make enough to meet its needs. Several nonessential amino acids are conditionally essential, which means they become essential under certain conditions.

*Explain the difference between a high-quality protein and a low-quality protein.

A high-quality or complete protein contains all essential amino acids in amounts that support protein deposition in muscles and other tissues, as well as supporting the growth of a young child. A low-quality or incomplete protein lacks or contains inadequate amounts of one or more of the essential amino acids.

*Trace the path of triglycerides from the liver to storage in adipose tissue.

After a fatty meal, the absorption of triglycerides results in an influx of triglycerides into the liver. Some of the fat remains in the liver, but a considerable amount of the lipid is incorporated into very-low-density lipoproteins (VLDLs). After the liver releases VLDL into the bloodstream, adipocytes and other cells can access the lipoproteins' lipid contents, particularly fatty acids, through the action of lipoprotein lipase. This enzyme cleaves the three fatty acids from the glycerol backbone of a triglyceride molecule in lipoproteins. As a result, the free fatty acids and glycerol can enter cells. After entering, three fatty acids can be attached to a glycerol molecule, re-creating a triglyceride molecule. Making triglycerides from fatty acids and glycerol molecules requires very little energy input. Therefore, triglyceride synthesis is the primary route for storing excess fatty acids, especially in adipocytes.

*What are the definitions of saturated, monounsaturated, and polyunsaturated fatty acids ?

An unsaturated fatty acid has at least two neighboring carbons within the chain that are missing two hydrogen atoms, and a double bond holds the two particular carbons together. A monounsaturated fatty acid has one double bond linking two carbon atoms. Polyunsaturated fatty acids have have two or more double bonds in their hydrocarbon chains.

*Describe the conversion of excess protein into glucose or fatty acids.

As mentioned earlier, cells preferentially use amino acids for protein synthesis rather than for energy. What happens if the diet provides an excess of amino acids and cells do not need energy? Under these conditions, the amino acids will be stripped of their nitrogen group and used to make either glucose or fat.

*Explain the difference between catabolism and anabolism.

Catabolism refers to metabolic pathways that break down larger molecules into smaller ones. Examples of catabolic reactions include the breakdown of glucose, fatty acid, and amino acid molecules to form carbon dioxide (CO2) and water (H2O). Catabolic reactions are considered "downhill," because they result in the release of more energy than is used to initiate the reactions. Heat comprises some of the energy that is released: "Heat of metabolism" helps the body maintain its normal temperature. Cells use the remaining energy to power chemical reactions. Anabolism refers to metabolic pathways that build larger molecules from smaller ones. Anabolic reactions include building glycogen from glucose molecules, triglycerides from glycerol and free fatty acids, and proteins from amino acids. Anabolic reactions are "uphill," because they require the input of more energy than is released by the reactions. The newly formed molecules store this extra "input" energy for later use by the body.

*Explain why one must be careful when planning vegan meals for children.

Children have higher protein and energy needs per pound of body weight than an adult. Because plant foods add bulk to the diet, vegan children are likely to eat far less food than adult vegans because they become full sooner during meals. Thus, very young vegans may be unable to eat enough plant foods to meet their protein and energy needs.

*Review information about measles on page 206 of the text

Children with protein-energy malnutrition do not grow and are very weak, irritable, and vulnerable to dehydration and infections, such as measles, that can kill them

*What is a coenzyme?

Coenzymes are a particular group of organic cofactors that often have B vitamins in their chemical structures; they release energy from macronutrients

***Discuss the importance of dietary fiber, and specific ways that it can be included in a healthy diet. Include the amount that is recommended, as well as types and their actions in the body.***

Dietary Fiber has extreme importance on an individual's health. The recommended daily allowance (RDA) for fiber is 25 to 30 g per day. For men, the Adequate Intake (AI) is 38 g per day. However for women, the AI is 25 g per day. However, the average American consumes only 16 grams which is half of the maximum recommended amount of daily fiber. Basically, fiber is a carbohydrate known as cellulose that cannot be digested by the human body due to its beta linkages. There are two types of fiber: insoluble and soluble. Insoluble fiber cannot be dissolved in water, which is going to be foods like oats and whole grains. They are going to provide bulk in the stool which prevents constipation. Soluble fiber can dissolve in water and is found in foods such as fruits. They slows down stomach emptying and glucose absorption. Additionally, soluble fiber lowers the blood cholesterol by interfering with the bile recycling process. Increasing your intake of fiber can also lower your likelihood of developing metabolic syndrome, colon cancer, and cardiovascular disease.

*List the major components of an amino acid.

Each amino acid has a carbon atom that anchors a hydrogen atom and three different groups of atoms: the amino or nitrogen-containing group, the R group (sometimes called the side chain), and the carboxylic acid group.

*List at least three ways to increase one's fiber intake.

Eat brown rice instead of white rice, Substitute whole-wheat pasta for regular pasta, Snack on pieces of fresh, frozen, or dried fruit, Include more nuts, beans, and seeds in your diet, Eat veggies as a snack

*List three food sources of cholesterol.

Eggs, Ice Cream, Beef

*Identify two causes each for high BUN and low BUN.

High - Congestive heart failure, heart attack, shock, kidney disease; Low - Liver failure, malnutrition, inadequate protein intake

*Identify at least three dietary sources of high-quality protein and three dietary sources of low-quality protein.

High = meat, fish, poultry, eggs, and milk; Low = quinoa, soy protein, beans, lentils, spinach

*Describe how cells utilize fatty acids as a source of energy when glucose is in short supply.

If cells do not have enough glucose to "burn" for energy, beta-oxidation of fatty acids increases, which produces excessive amounts of acetyl CoA

*Identify the major function of carbohydrate in the body

In addition to being a source of energy, certain carbohydrates serve as the "glue" that holds cells together in tissues.

*List the primary sources of added sugars in the typical American diet.

Regular soft drinks and energy drinks, cookies, chips, and many other types of processed snack

*What is a ketone body, and under what conditions does the body form excessive ketone bodies?

Ketone bodies are chemicals that result from the incomplete breakdown of fat. Muscle and brain cells can use ketone bodies for energy, but a condition commonly called KETOSIS occurs when these compounds accumulate in the blood.

*List the major metabolic responses that occur in muscle, adipose tissue, and the liver during starvation.

Liver and muscle glycogen stores become depleted with extended fasting. When that situation occurs, muscle cells begin to rely more on fatty acids for energy. Adipose tissue responds to starvation by increasing lipolysis, and as a result, the level of fatty acids increases in the bloodstream. The fatty acids supply some energy for muscle tissue, and they are also taken up by the liver. Eventually, the rapid influx of fatty acids into the liver becomes too much for the organ's cells to handle. When this occurs, liver cells rely on ketogenesis to convert acetyl CoA into ketone bodies.

*Describe the two pathways that metabolize alcohol.

Main- alcohol dehydrogenase pathway, for low to moderate amounts of alcohol, most of the alcohol is converted to acetaldehyde, a highly toxic substance then the enzyme aldehyde dehydrogenase helps convert acetaldehyde to acetate, a less toxic substance. Acetate can then be converted to acetyl CoA Secondary- microsomal ethanol-oxidizing system, for excessive drinking, also produces acetaldehyde that must be further processed to yield acetyl CoA

* A disaccharide is a simple sugar comprised of two monosaccharides. __________ - Disaccharide composed of two glucose molecules; "malt sugar" __________ - Disaccharide composed of a glucose and a fructose molecule; "table sugar" _________ - Disaccharide composed of a glucose and a galactose molecule; "milk sugar"

Maltose, Sucrose, Lactose

*What is ATP, and what is its role in living cells?

Most of the energy released by the break down of macronutrients is captured in chemical form as adenosine triphosphate (ATP). ATP is comprised of adenosine bound to three (tri-) inorganic phosphate groups (Pi). Cells can use the energy released in this reaction for anabolic activities.

*Can fatty acids make glucose?

No

*List at least three major risk factors for developing CVD that are nonmodifiable and at least five that are modifiable.

Nonmodifiable Risk Factors: -Family history of CVD (especially before 60 years of age) -Increasing age -Race/ethnic background -Male sex Modifiable Risk Factors: -Hypertension -Diabetes mellitus -Elevated blood cholesterol (especially LDL cholesterol) -Excess body fat -Physical inactivity -Tobacco use or exposure to tobacco smoke -Untreated sleep apnea

*What is the difference between a nutritive sweetener and a nonnutritive sweetener? _________ sweeteners are substances that sweeten and contribute energy to foods. Each gram of mono- or disaccharide supplies 4 kcal. ___________ sweeteners are a group of synthetic compounds that are intensely sweet tasting compared to sugar. Very small amount is needed to sweeten food. Supply no energy per serving. Can help control energy intake.

Nutritive, Nonnutritive

*Describe four health benefits of omega-3 fatty acid consumption.

Omega-3 Fats May Reduce the Risk of Developing: Heart disease Preterm birth Depression, including postpartum depression Dental disease Alzheimer's disease Certain cancers Arthritis Omega-3 Fats May Improve: Immune function Cognitive development in infants

*Consequences of poorly controlled Type I or Type II Diabetes Mellitus

Over time, untreated or poorly controlled hyperglycemia damages nerves, organs, and blood vessels. In fact, poorly controlled diabetes is a major cause of heart disease; kidney failure; blindness; and poor blood circulation, particularly of the lower limbs, which can require amputation.

*Compare and contrast the different types of vegetarian diets.

Pescavegetarian - Milk, milk products, and eggs; fish but no other animal foods *Semivegetarian - All except red meats *Lactovegetarian - Milk and milk products; no animal flesh or eggs Ovovegetarian - Eggs but no other animal foods *Lactoovovegetarian - Milk and milk products and eggs but no other animal foods *Vegan - No animal foods

*Explain conditions that can cause the body to be in positive nitrogen balance and in negative nitrogen balance.

Positive balance occurs during periods of rapid growth such as pregnancy, infancy, and puberty, and when people are recovering from illness or injury. Negative balance occurs during starvation, serious illnesses, and severe injuries

*How are proteins chemically different from carbohydrates or lipids?

Proteins are complex organic molecules that are chemically similar to lipids and carbohydrates because they contain carbon, hydrogen, and oxygen atoms. Proteins, however, also contain nitrogen, an element cells need to make a wide array of important biological compounds such as enzymes and hormones.

*What are four functions of lipids in the body?

Provide and store energy (triglycerides) Form and maintain cell membranes Produce steroid hormones Insulate the body against cold temperatures Cushion the body against bumps and blows Form body contours Absorb fat-soluble vitamins and phytochemicals

*Suggest at least four ways people can reduce their intakes of saturated fats and increase their intakes of unsaturated fats.

Reduce intake of fried foods. Purchase lean meats and trim visible fat from meat before cooking. Before eating cooked meat, trim and discard any remaining visible fat. Try replacing some fatty foods with reduced-fat or fat-free alternatives. -replace foods that contain saturated fat with nuts -Use less creamy salad dressings on salads. When in restaurants, order oil-and-vinegar salad dressings or creamy dressings "on the side" so the amount added is easy to control. Use one-quarter less butter, oil, or margarine than is indicated in recipes. Use olive or canola oils in recipes that call for vegetable oil.

*List at least four different functions of proteins in the body.

To build new cells and many functional components of cells As a component of hardened structures, such as hair and nails As enzymes to speed chemical reactions As lubricants to ease movement In clotting compounds in blood To build antibodies that fight disease organisms As compounds that help maintain fluid and pH balance As transporters and to make certain hormones As an energy source (a minor function, under usual conditions)

*Compare type 1, type 2, and gestational diabetes.

Type 1 diabetes is an autoimmune disease that occurs when certain immune system cells malfunction and do not recognize the body's own beta cells. As a result, the immune system cells attack and destroy the beta cells, and the affected person must obtain an exogenous ("outside the body") source of insulin regularly. The most common form of diabetes is type 2 diabetes. Beta cells of people with type 2 diabetes usually produce insulin, but the hormone's target cells are insulin-resistant, which means they do not respond properly to the hormone and do not allow glucose to enter them. As a result, the level of glucose in the bloodstream rapidly becomes abnormally elevated, and the signs and symptoms of diabetes occur. gestational diabetes - type of diabetes that develops in some pregnant women, can go away

*Know both the composition and the function of chylomicrons, VLDL, LDL and HDL

Very-low-density lipoprotein (VLDL) is a lipoprotein made in the liver and carries much of the triglycerides in the bloodstream; second biggest, mostly a triglyceride Low-density lipoprotein (LDL) is a lipoprotein that carries cholesterol into tissue. Elevated LDL is strongly linked to increased risk of CVD; mostly cholesterol, third biggest High-density lipoprotein (HDL) is a lipoprotein that transports cholesterol away from tissues to the liver to be eliminated. Low HDL is linked to increased risk of CVD; smallest, mostly protein A chylomicron is a type of lipoprotein formed in enterocytes to transport lipids away from the GI tract; mostly a triglyceride, the biggest of all four All are comprised of protein, cholesterol, triglycerides, and phospholipids

*Explain why protein-energy malnutrition (PEM) is especially devastating for young children.

When food is limited, it is often more difficult for children than for adults to obtain nutritionally adequate diets. Adults may be able to consume enough plant proteins to meet their protein and energy needs, but children have smaller stomachs and higher energy and protein needs per pound of body weight than adults.

*List ways in which you can reduce your intake of protein from animal foods, starting with your usual food choices.

adding sunflower seeds, kidney or black beans, cashews, and bread cubes to the salad boosts the amount of protein and provides a complete mix of amino acids. To increase the essential amino acid content of the salad even further, add a small amount of hard-cooked egg, shredded cheese, or tofu to it.

*egg white protein is called

albumin

*Glucagon is from the _____ cells

alpha

*What body tissues can be converted to glucose?

amino acids and pyruvate? stored fat?

*Insulin if from the _____ cells

beta

*How does excess carbohydrate consumption increase body fat deposits?

carbohydrates converted to glucose and that extra glucose molecules "spare" (conserve) fatty acids by enabling the lipid molecules to be made into triglycerides and stored for ATP production in the future. This process explains why people who eat excess carbohydrates can gain body fat

*Identify substances that the human body can use as fuel.

carbohydrates, lipids, proteins, and alcohol can be utilized for energy

*Which hormone or hormones promote anabolism? Which hormone or hormones promote catabolism?

catabolism- epinephrine, cortisol, glucagon anabolism- insulin

*Which form of energy is stored in macronutrients?

chemical?

*Explain the differences between glycogenesis and glycogenolysis, and lipogenesis and lipolysis. Why is gluconeogenesis repeated in Table 8.8?

glycogenesis: if glycose and ATP are inexcess glycose is converted to glycogen for storage and liver glycogenolysis: glycogen stored in liver is converted to glycose peptides lipogenesis: the metabolic formation of fat lipolysis: break down the fat because it happens with both carbs and proteins?

*Relationship of protein intake to muscle building

help form tissues such as muscles

*Bernard's total blood cholesterol level is 195 mg/dL, and his HDL cholesterol level is 62 mg/dL. Based on this information, does Bernard have a high risk or low risk of developing CVD? Explain your answer.

high - HDL is over 40, and because he is almost over 200 on total cholesterol

*List three common signs or symptoms of food allergy.

hives, swollen or itchy lips; a scaly skin rash (eczema); difficulty swallowing; wheezing and difficulty breathing; and abdominal pain, vomiting, and diarrhea

*Describe at least two effects of alcohol on the body.

impairment of reasoning, increased sociability, loss of balance, slurred speech

*Explain the basic steps involved in protein synthesis.

in pictures on phone

*What is the FDA definition of a food product labeled "whole grain"?

intact, ground, cracked, or flaked seeds of cereal grains

*alpha-linolenic acid

is an 18-carbon polyunsaturated fatty acid with three double bonds

*Describe the absorption of carbohydrates by the small intestine and their transport to the liver.

Absorption of monosaccharides occurs almost exclusively in the small intestine. The monosaccharides enter the capillary network of the villus. The hepatic portal vein transports the monosaccharides to the liver.

*Compare transamination and deamination.

Deamination is the process of removing the nitrogen-containing group (usually NH2) from an unneeded amino acid. Transamination occurs when the nitrogen-containing group is transferred to another substance to make a nonessential amino acid.

*Explain why insulin resistance may lead to the development of nonalcoholic fatty liver disease and metabolic syndrome.

In cases of obesity, the increase in adipose tissue often results in abnormal metabolic changes in fat and muscle cells. These changes make the cells resistant or unresponsive to the effects of insulin. Insulin resistance in muscle cells and adipocytes occurs because the insulin receptors no longer function properly. Insulin resistant cells do not take up glucose and fatty acids from the bloodstream and store energy effectively. Thus, blood glucose levels stay abnormally elevated (hyperglycemia) long after a meal is consumed. levels of glucose and fatty acids in blood increase dramatically. In the liver, the influx of fatty acids stimulates triglyceride synthesis. The excess fat can accumulate in liver cells and lead to a condition called nonalcoholic fatty liver. When liver cells become insulin resistant, their ability to regulate glycogen synthesis and gluconeogenesis becomes altered. The liver continues to produce glucose and release the monosaccharide into the bloodstream. As the blood glucose level rises even higher, the pancreas secretes more insulin. This vicious cycle results in metabolic syndrome

*Explain the relationship between fiber and normal bacteria of the colon.

The fiber in oats is not digested by the human small intestine, so the fiber eventually enters the large intestine. Then "friendly" intestinal bacteria that reside in the large intestine can break down (ferment) the soluble fiber and metabolize the fermentation products for energy.

*Production of urea

The liver can use the ammonia to make urea, a metabolic waste product that is released into the bloodstream. The kidneys filter urea, small amounts of ammonia, and creatinine (a nitrogen-containing waste produced by muscles) from blood and eliminate the compounds in urine. The process of deamination results in the production of the highly toxic compound ammonia. In an energy-requiring process, the liver converts ammonia to urea and releases it into the blood. The kidneys pick up urea and other nitrogen-containing wastes and eliminate them in urine.

*Compare the composition of a chylomicron, VLDL, LDL, and HDL.

chylomicrons a lipoprotein transports lipids away from GI tract VLDL is a lipoprotein made in liver. Carries much of the triglycerides in blood LDL is a lipoprotein, carries cholesterol into tissue. HDL is a lipoprotein, carries cholesterol away from tissues to liver

*What is dietary fiber?

complex carbohydrates comprised of monosaccharides connected by bonds that humans cannot digest

*What causes anaphylactic shock?

it is caused by a serious drop in blood pressure that affects the whole body when a sensitive person is exposed to a food allergen

*Explain why cholesterol is necessary for health.

it is essential to health as it is an integral component of every cell membrane in the body

*Identify at least three signs of metabolic syndrome.

large waist consumption, hypertension, chronically elevated fasting blood fats, low fasting high-density lipoprotein cholesterol, and high fasting blood glucose

*Which tissues are the primary sites for glycogen synthesis and storage?

liver, muscle and fat cells

*Identify nutrients that can be low or lacking in a vegan's diet.

lower calcium intakes, vitamin B-12, vitamin D, iron, zinc

*Discuss the series of physiological changes that occur in arteries and contribute to the development of CVD.

smooth lining, damage, cholesterol deposited to repair it, plaque roughens surface, slows blood flow, clot forms, then complete blockage occurs

*What is lecithin?

the most abundant phospholipid in food, it contains choline (co'-leen), a water-soluble, vitamin-like compound that has many functions

*Summarize the effects of alcohol on the liver.

Alcohol directly affects the liver by disrupting the normal metabolism of glucose, fatty acids, and amino acids. (a) NADH accumulates in liver cells, and the amount of NAD+ becomes depleted. (b) When NADH accumulates in liver cells, more pyruvate is converted to lactic acid. (c) Hypoglycemia occurs as a result of the accumulation of NADH. (d) Because of the lack of NAD+, the activity of the citric acid cycle slows. (e) Some acetyl CoA is metabolized for energy, but (f) liver cells use most of the excess acetyl CoA molecules to make fatty acids for triglyceride synthesis.

*Identify the two essential fatty acids, and describe key signs of an essential fatty acid deficiency.

Alpha-linolenic acid (omega-3) and linoleic acid (omega-6) are the two essential fatty acids and signs of an essential fatty acids deficiency include: babies not growing properly, scaly skin, hair loss, and poor wound healing.

*How does an omega-3 fatty acid differ from an omega-6 fatty acid?

An omega-3 fatty acid is a polyunsaturated fatty acid with its first double bond at the third carbon from the omega end of the molecule and an omega-6 fatty acid is a polyunsaturated fatty acid with its first double bond occurring at the sixth carbon from the omega end of the chain.

*Discuss the metabolic processes that occur during an overnight fast.

As blood glucose levels fall during the early part of an overnight fast, the pancreas responds by releasing glucagon. Glucagon instructs liver cells to increase glycogenolysis. This process helps maintain blood glucose levels within normal limits, but the supply of liver glycogen is limited and becomes depleted over the course of about 12 hours. When the liver's glycogen supply is "on empty," glucagon stimulates liver cells to convert certain amino acids derived from muscle tissue into pyruvate and then glucose (gluconeogenesis). During this time, the liver and muscle tissue use mainly fatty acids for fuel.

*Explain how insulin and glucagon regulate blood glucose levels.

As the blood glucose level begins to rise, the pancreas responds by secreting insulin into the bloodstream. Insulin helps reduce blood glucose to normal levels, because the hormone enables glucose to enter most cells. The hormone also enhances energy storage by promoting cellular fat, glycogen, and protein production. If an individual ignores the hunger signals and does not eat, the alpha cells in the pancreas secrete glucagon. Glucagon opposes insulin's effects by promoting the breakdown of glycogen. This process, called glycogenolysis (lysis = break) releases glucose into the bloodstream and, as a result, keeps blood glucose from dropping too low (Fig. 5.14). Glucagon also stimulates liver and kidney cells to produce glucose from certain amino acids, the basic molecules that make up proteins. Furthermore, glucagon stimulates lipolysis (lipo = fat), the breakdown of triglyceride (fat) into glycerol and fatty acids. As a result, glycerol and fatty acids rapidly enter into the bloodstream. The liver uses glycerol to produce glucose, and most cells, including muscle cells, can metabolize fatty acids for energy. Although the body can convert certain amino acids into glucose, it cannot use fatty acids to make glucose.

*Discuss what parents of infants with PKU can do to help their children grow and develop normally.

As the children grow and mature, fruits, vegetables, and special low-protein foods can be added to the formula diet. However, children and adults with the disorder need to avoid foods that are rich sources of phenylalanine, such as nuts, milk products, eggs, meats, and other animal foods. Additionally, people with PKU should not consume diet soft drinks and other foods and beverages containing the alternative sweetener aspartame, because the sweetener is a source of phenylalanine

*Describe what happens to the fat in a piece of fried chicken as it undergoes digestion and absorption; include the roles of bile, CCK, pancreatic lipase, villi, and micelles.

As the food enters the stomach, the organ's acidic environment activates the lipase, enabling some lipid breakdown to occur. The small intestine, however, is the primary site of lipid digestion. As the fatty chyme leaves the stomach and enters the small intestine, it stimulates certain intestinal cells to secrete the hormones cholecystokinin (kol'-e-sis'-toe-kye'-nin) (CCK) and secretin. Secretin stimulates the liver to produce bile and causes the pancreas to secrete bicarbonate-rich pancreatic juice, which is necessary to create an alkaline environment in the small intestine. CCK signals the pancreas to secrete digestive enzymes, including pancreatic lipase, into the duodenum of the small intestine. CCK also triggers the gallbladder to release stored bile and the sphincter that controls the flow of bile and pancreatic juice into the duodenum to open. Bile contains bile salts, compounds that enhance digestion and absorption by emulsifying lipids in the watery environment of the small intestine. The majority of lipid absorption occurs in the small intestine, particularly in the duodenum and jejunum. Glycerol, fatty acids, monoglycerides, cholesterol, and phospholipid fragments are the end products of lipid digestion. Short- and medium-chain fatty acids diffuse into the absorptive cells of villi, where they enter the capillary network (bloodstream). Absorption of long-chain fatty acids, however, requires additional steps. When exposed to watery digestive juice, hydrophobic long- chain fatty acids, along with bile, cholesterol, fat-soluble vitamins, and other products of lipid digestion, pack together into round structures called micelles (my'-cells). The bile salts create a shell around each micelle, which allows the small lipid clusters to remain suspended in the watery digestive juices. When micelles come close to the villi, their contents diffuse into absorptive cells (enterocytes).

*Explain why consuming foods or beverages that contain aspartame may be dangerous for certain people.

Aspartame consists of phenylalanine and aspartic acid, two amino acids (the molecules that comprise proteins). Some people must avoid aspartame and certain protein-rich foods because they have phenylketonuria (PKU) (fen′-nul-keet′-en-yur′-e-ah), a rare inherited disorder that results in abnormal phenylalanine metabolism.

*Explain why some lactose-intolerant individuals are able to consume yogurt, cheese, and small amounts of milk without experiencing intestinal discomfort.

Because milk loses most of its lactose content when it is processed to make aged cheeses, such as cheddar and Swiss, and the bacteria used to make yogurt convert much of the lactose in milk to lactic acid, and the microbes assist with the digestion of the remaining lactose even after the yogurt is eaten

*Discuss the health benefits of including soluble and insoluble fiber in diets.

Eating high-fiber foods may reduce a person's risk of obesity, type 2 diabetes, certain intestinal tract disorders, and cardiovascular disease, which includes heart disease and stroke. People who often eat foods that contain insoluble fiber have easier and more regular bowel movements, and they are less likely to strain while having bowel movements than people whose diets lack fiber. Diets rich in fiber, particularly soluble types of fiber, can reduce the risk of cardiovascular disease by reducing blood cholesterol levels. People who are trying to lose excess body fat may find it helpful to add more fiber-rich foods to their diets. High-fiber foods tend to be "filling" by increasing the volume of food eaten, which results in satiety.

*Describe the roles of diet, exercise, and medication in the treatment of diabetes.

Either multiple daily insulin injections and insulin pumps enable people with type 1 diabetes to manage their condition efficiently. Some people with type 2 diabetes can take oral medication to stimulate their bodies' insulin production. Regular physical activity improves diabetes control as well as overall health and well-being. Physical activity increases glucose uptake by muscles, reducing blood glucose levels and improving the body's insulin response. Regular physical activity also can also help overweight people with type 2 diabetes lose weight. By losing even a small amount of excess body fat, people with type 2 diabetes can often reduce their insulin resistance. People may reduce their risk of type 2 diabetes by avoiding excess body fat, exercising daily, and improving their diets. Avoiding high amounts of red meat, processed meats, French fries, high-fat dairy foods, and refined sugars and starches can reduce your risk.Eat more more poultry, fish, and fiber-rich whole grains, fruits, and vegetables.

*Explain the differences between the glucogenic and ketogenic pathways for using proteins for energy.

Glucogenic amino acids are those that are broken down into either pyruvate or intermediates of the citric acid cycle. Amino acids that enter the catabolic energy pathways as acetyl CoA are ketogenic. The amount of ATP formed by the catabolism of a carbon skeleton depends on where it entered into the catabolism pathways.

*What can/cannot be made from acetyl CoA molecules or fatty acids?

Two-carbon molecule formed from pyruvate?

*linoleic acid

is an 18-carbon polyunsaturated fatty acid with two double bonds

*Police bring a 2-year-old child into a clinic; the child is weak and has has arms and upper legs that are so thin, the skin hangs from them. The police report indicates the child was severely neglected by the parents. According to this information, is this child suffering from kwashiorkor, marasmus, or anorexia nervosa? Choose one of these conditions and explain why you selected it.

marasmic - a form of undernutrition that results in a child with kwashiorkor who then starts to not consume enough energy; characterized by edema and wasting

*Explain why an egg white changes its appearance when it is cooked.

the protein becomes denatured

*Name two pancreatic enzymes that break down protein in the small intestine.

trypsin and chymotrypsin

*fatty acids - ______ carbons come apart at a time

two

*What happens if excess CHO is consumed?

we shift to using that excess CHO for energy instead of using fat that we have stored