A & P CH 24

Glucose serves as the initial reactant.
A) Krebs cycle and electron transport chain.
B) Glycolysis
C) Krebs cycle and electron transport chain

B) Glycolysis

Involves the removal of hydrogen
electrons and CO2 from the substrate
molecule.
A) Krebs cycle and electron transport chain.
B) Glycolysis
C) Krebs cycle and electron transport chain

C) Krebs cycle and electron transport chain

Occurs in the cytosol of a cell.
A) Krebs cycle and electron transport chain.
B) Glycolysis
C) Krebs cycle and electron transport chain

B) Glycolysis

Produces the most ATP
A) Krebs cycle and electron transport chain.
B) Glycolysis
C) Krebs cycle and electron transport chain

A) Krebs cycle and electron transport chain.

Involves the use of oxygen to pick up
excess hydrogen and electrons.
A) Krebs cycle and electron transport chain.
B) Glycolysis
C) Krebs cycle and electron transport chain

C) Krebs cycle and electron transport chain

Breakdown of glycogen to release
glucose.

glycogenolysis

Formation of glucose from proteins or
fats.

gluconeogenesis

Storage of glucose in the form of
glycogen.

glycogenesis

Breakdown of glucose to pyruvic acid.

glycolysis

Synthesis of lipids from glucose or
amino acids.

lipogenesis

Splitting of triglycerides into glycerol
and fatty acids.

lipolysis

Conversion of fatty acids into acetyl
groups.

beta oxidation

Formation of ketone bodies.

ketogenesis

Beta oxidation is the initial phase of fatty acid oxidation, and it occurs in the cytoplasm.

F

The increased use of noncarbohydrate molecules for energy to conserve glucose is called glucose sparing.

T

Except for lactose and some glycogen, the carbohydrates we ingest are mainly from animals

F

The term essential nutrient refers to the chemicals that can be interconverted in the liver so that the body can maintain life and good health.

F

The most abundant dietary lipids in the diets of most Americans are triglycerides.

T

There are no complete proteins. All animal products should be eaten with plant material to make a complete protein.

F

The body is considered to be in nitrogen balance when the amount of nitrogen ingested in lipids equals the amount excreted in urine.

F

The amount of protein needed by each person is determined by the age, size, and metabolic rate of the person.

T

Vitamins are inorganic compounds that are essential for growth and good health.

F

Cellular respiration is an anabolic process.

F

Glycolysis is a series of six chemical steps, most of which take place in the mitochondria.

F

Glycogenesis begins when ATP levels are high, and glucose entering cells is phosphorylated to glucose-6-phosphate and converted to its isomer, glucose-1-phosphate.

T

All athletes require diets high in protein and calories in order to perform and to maintain their muscle mass.

F

In order for amino acids to be oxidized for energy, the amine group (NH2) must be removed.

T

Including the ATP from glycolysis, the cell gains 34 ATP molecules from aerobic metabolism of one 35)
glucose molecule.

F

The body requires adequate supplies of only three minerals (calcium, sodium, chloride) and trace 36)
amounts of all others.

F

Processes that break down complex molecules into simpler ones are anabolic.

F

For use as fuel, all food carbohydrates are eventually transformed to glucose.

T

Triglycerides and cholesterol do not circulate freely in the bloodstream.

T

Normal body temperature range is 98.6-100°F, regardless of external temperature.

F

A deficit of potassium can cause rickets.

F

It would not be healthy to eliminate all fats from your diet because they serve a useful purpose in maintaining the body.

T

The body’s thermoregulatory centers are located in the thalamus.

F

Carbohydrate and fat pools are oxidized directly to produce cellular energy, but amino acid pools must first be converted to a carbohydrate intermediate before being sent through cellular
respiration pathways.

T

High levels of HDLs are considered good.

T

Diets high in cholesterol and saturated fats tend to produce high HDL concentrations.

F

Ghrelin, produced by the stomach, is a powerful appetite stimulant.

T

Peptides called NPY and AgRP are powerful appetite enhancers.

T

The primary function of carbohydrates is energy production within cells.

T

The molecule that serves as the major source of readily available fuel for neurons and blood cells is
________.

D) glucose

Which of the choices below is not a fate of carbohydrate taken into the body?
A) lipogenesis
B) glycogenesis
C) conversion to a nucleic acid
D) ATP production
E) amino acid synthesis

C) conversion to a nucleic acid

Dietary fats are important because they ________.

A) help the body absorb fat-soluble vitamins

Cholesterol, though it is not an energy molecule, has importance in the body because it ________.

is a stabilizing component of the plasma membranes and is the parent molecule of steroid hormones

Which of the following statements best describes complete protein?
A) derived from meat and fish only
B) must meet all the body’s amino acid requirements for maintenance and growth
C) meets all the minimum daily requirements for a healthy diet
D) derived only from legumes and other plant material

B) must meet all the body’s amino acid requirements for maintenance and growth

The term metabolism is best defined as ________.
A) biochemical reactions involved in building cell molecules or breaking down molecules for energy
B) a measure of carbohydrate utilization, typically involving measurement of calories
C) the number of calories it takes to keep from shivering on a cold day
D) the length of time it takes to digest and absorb fats

A) biochemical reactions involved in building cell molecules or breaking down molecules for energy

The term metabolic rate reflects the ________.
A) energy needed to make all organic molecules
B) loss of energy to perspiration
C) energy the body needs to perform only its most essential activities
D) loss of organic molecules in urine

C) energy the body needs to perform only its most essential activities

When proteins undergo deamination, the waste substance found in the urine is mostly________.
A) ketone bodies
B) acetyl CoA
C) ammonia
D) urea

D) urea

It is important to ensure that your diet is adequately rich in vitamins because ________.
A) all vitamins are water soluble and pass out of the body too quickly to ensure utilization
B) very few foods contain vitamins
C) most vitamins are coenzymes needed to help the body utilize essential nutrients
D) vitamins provide protection against the common cold

C) most vitamins are coenzymes needed to help the body utilize essential nutrients

Oxidation-reduction reactions are catalyzed by which of the following enzymes?
A) dehydrogenases and oxidases
B) synthetases and lipases
C) kinases and phosphorylases
D) phosphatases and kinases

A) dehydrogenases and oxidases

Which of the choices below describes the pathway of cellular respiration (the complete oxidation of glucose)?
A) lipolysis, glycogenolysis, beta oxidation
B) glycogenesis, lipogenesis, electron transport chain
C) glycolysis, Krebs cycle, electron transport chain, oxidative phosphorylation
D) gluconeogenesis, Krebs cycle, lipolysis

C) glycolysis, Krebs cycle, electron transport chain, oxidative phosphorylation

Anabolism includes reactions in which ________.
A) larger molecules or structures are built from smaller ones
B) carbohydrate utilization increases
C) ketone bodies are formed
D) structural proteins are used as a potential energy source

A) larger molecules or structures are built from smaller ones

Catabolism would be best described as a process that ________.
A) builds up triglycerides during the postabsorptive state
B) causes a decline in circulating ketone bodies
C) elevates glucagon levels
D) breaks down complex structures to simpler ones

D) breaks down complex structures to simpler ones

The primary function of cellular respiration is to ________.
A) break down food molecules and generate ATP
B) determine the amount of heat needed by the human body
C) efficiently monitor the energy needs of the body
D) provide the body with adequate amounts of vitamins and minerals

A) break down food molecules and generate ATP

The process of breaking triglycerides down into glycerol and fatty acids is known as ________.
A) lipolysis
B) fat utilization
C) lipogenesis
D) gluconeogenesis

A) lipolysis

Which of the following mechanisms produces the most ATP during cellular respiration?
A) oxidation-reduction reactions
B) oxidative phosphorylation
C) substrate-level phosphorylation
D) oxidation reactions

B) oxidative phosphorylation

Lipogenesis occurs when ________.
A) there is a shortage of fatty acids
B) cellular ATP and glucose levels are high
C) glucose levels drop slightly
D) excess proteins are transported through the cell membrane

B) cellular ATP and glucose levels are high

Oxidative deamination takes place in the ________.

liver

Transamination is the process whereby the amine group of an amino acid is ________.
A) transferred to acetyl CoA
B) converted to ammonia
C) transferred to a keto acid
D) converted to urea

C) transferred to a keto acid

Glycogen is formed in the liver during the ________.
A) starvation period
B) absorptive state
C) period when the metabolic rate is lowest
D) postabsorptive state

B) absorptive state

Which of the following is a normal consequence of the activation of the heat-promoting center?
A) sympathetic sweat gland activation
B) release of epinephrine
C) vasodilation of cutaneous blood vessels
D) increase in ADH production

B) release of epinephrine

Gluconeogenesis is the process in which ________.
A) glycogen is formed
B) glucose is converted into carbon dioxide and water
C) glycogen is broken down to release glucose
D) glucose is formed from noncarbohydrate precursors

D) glucose is formed from noncarbohydrate precursors

Glycolysis is best defined as a catabolic reaction based upon the ________.
A) conversion of pyruvic acid into carbon dioxide and water
B) formation of sugar
C) conversion of glucose into carbon dioxide and water
D) conversion of glucose into two molecules of pyruvic acid
Answer: D

D) conversion of glucose into two molecules of pyruvic acid

What is the outcome of ketosis?
A) water retention and edema
B) glycogen buildup
C) metabolic alkalosis
D) metabolic acidosis
E) glucogenesis

D) metabolic acidosis

Which of the choices below happens during the absorptive state?
A) Anabolic processes exceed catabolic ones.
B) Only glucose metabolism occurs.
C) Catabolic processes exceed anabolic ones.
D) No metabolism occurs.

A) Anabolic processes exceed catabolic ones.

In the case of a person who consumes a normal, balanced diet, proteins are essential to the body for all of the following except ________.
A) production of energy
B) production of enzymes, clotting factors, and antibodies
C) formation of functional molecules like hemoglobin and cytochromes
D) production of some hormones

A) production of energy

The most abundant dietary lipids are ________.
A) triglycerides
B) fatty acids
C) cholesterol
D) phospholipids

A) triglycerides

Loss of heat in the form of infrared waves is termed ________.
A) convection
B) radiation
C) evaporation
D) conduction

B) radiation

Which hormone directs essentially all the events of the absorptive state?
A) insulin
B) growth hormone
C) epinephrine
D) thyroid hormone

A) insulin

Prostaglandins play a role in ________.
A) skeletal muscle contraction
B) noninflammatory responses
C) control of blood pressure
D) control of blood volume

C) control of blood pressure

Which of the following is the most important function of the liver?
A) carbohydrate and lipid metabolism
B) synthesis of bile salts
C) protein metabolism
D) processing of drugs and hormones and activation of vitamin D

C) protein metabolism

As the body progresses from the absorptive to the postabsorptive state, only the ________ continues to burn glucose while every other organ in the body mostly switches to fatty acids.
A) spleen
B) pancreas
C) liver
D) brain

D) brain

In gluconeogenesis, during the postabsorptive state, amino acids and ________ are converted to glucose.
A) glycogen
B) glycerol
C) glyceraldehyde
D) glucagon

B) glycerol

In the liver, the amine group of glutamic acid is removed as ________ in the oxidative state.
A) pyruvic acid
B) glyceraldehyde
C) oxaloacetic acid
D) ammonia

D) ammonia

Which of the choices below is not a mechanism of heat production?
A) vasoconstriction of cutaneous blood vessels
B) enhanced thyroxine release
C) shivering
D) sweating

D) sweating

Heat-loss mechanisms do not include ________.
A) the evaporation of sweat
B) reducing activity
C) behavior measures such as wearing light, loose clothing
D) vasoconstriction of peripheral blood vessels

D) vasoconstriction of peripheral blood vessels

The amount of ________ produced is probably the most important hormonal factor in determining BMR.
A) prolactin
B) ADH
C) thyroxine
D) norepinephrine

C) thyroxine

When ketone bodies are present in the blood and urine in large amounts, it usually indicates increased metabolism of ________.
A) fatty acids
B) glycogen
C) lactic acid
D) amino acids
Answer: A

A) fatty acids

Many factors influence BMR. What is the most critical factor?
A) the way an individual metabolizes fat
B) an individual’s body weight
C) the ratio of surface area to volume (weight) of the body
D) the way skeletal muscles break down glycogen

C) the ratio of surface area to volume (weight) of the body

The primary reason elderly people should decrease their caloric intake is that ________.
A) they have a higher metabolic rate and do not need large amounts of food
B) muscle mass and metabolism decline with age
C) their appetite begins to diminish
D) they spend most of the day at rest, and their food will quickly turn to fat

B) muscle mass and metabolism decline with age

Which of the choices below is not a major route of heat exchange?
A) radiation
B) evaporation
C) conduction/convection
D) shivering

D) shivering

Which of the following statements is a false or incorrect statement?
A) The amino acid pool is the body’s total supply of amino acids in the body’s proteins.
B) Amino acids can be used to supply energy only after being converted to a carbohydrate
intermediate.
C) Excess carbohydrate and fat can be stored as such, whereas excess amino acids are oxidized
for energy or converted to fat or glycogen for storage.
D) Fats and carbohydrates are oxidized directly to produce cellular energy.

A) The amino acid pool is the body’s total supply of amino acids in the body’s proteins.

Which of the following molecules are considered key molecules at metabolic crossroads?
A) glucose-6-phosphate, lactic acid, acetyl CoA
B) glucose-6-phosphate, pyruvic acid, acetyl CoA
C) ATP, pyruvic acid, lactic acid
D) acetone, beta-hydroxybutyric acid, ATP

B) glucose-6-phosphate, pyruvic acid, acetyl CoA

Which of the following nutrients yield the highest amount of energy per gram when metabolized?
A) fats
B) proteins
C) foods and beverages high in caffeine
D) vitamins and minerals

A) fats

Which of the following does not occur in the mitochondria?
A) formation of malic acid from fumaric acid
B) glycolysis
C) Krebs cycle
D) electron transport

B) glycolysis

Which of the following is not true of beta oxidation?
A) Fatty acids are broken into acetic acid fragments.
B) It occurs in the mitochondrion.
C) It involves the anabolism of fats.
D) Every second carbon is reduced.

C) It involves the anabolism of fats.

Select the correct statement about proteins.
A) Catabolic steroids (hormones) accelerate the rate of protein synthesis.
B) Proteins can be synthesized in the body if most of the amino acids are present.
C) Proteins will be used by most cells for ATP synthesis if insufficient carbohydrates are
ingested.
D) Strict vegetarians need not worry about adequate protein intake, as most vegetables are
almost perfect sources of amino acids.

C) Proteins will be used by most cells for ATP synthesis if insufficient carbohydrates are ingested.

Oxidation reduction reactions ________.
A) are rarely coupled together
B) occur via the gain of hydrogen or the loss of oxygen
C) utilize hydrogenases
D) may involve the loss of hydrogen and electrons

D) may involve the loss of hydrogen and electrons

What process primes a molecule to change in a way that increases its activity, produces motion, or
does work?
A) glycolysis
B) cellular respiration
C) phosphorylation
D) beta oxidation

C) phosphorylation

Which of the choices below is not a source of glucose during the postabsorptive state?
A) lipolysis in adipose tissues and the liver
B) absorption of glucose from the GI tract
C) glycogenolysis in the liver
D) catabolism of cellular protein
Answer: B

…

Which of the following is correct?
A) Oxidation of FADH2 eventually yields four ATP via oxidative phosphorylation.
B) Most of the ATP are produced by substrate-level phosphorylation.
C) Most ATP from cellular respiration are produced directly in the Krebs cycle.
D) Glycolysis relies on substrate-level oxidation for the four ATP produced in this pathway.
Answer: A

…

Which of the following food groups are considered good sources of complete proteins?
A) lima beans, kidney beans, nuts, and cereals
B) eggs, milk, yogurt, meat, and fish
C) corn, cottonseed oil, soy oil, and wheat germ
D) egg yolk, fish roe, and grains
Answer: B

…

Conditions that promote the oxidative deamination and energy use of amino acids include ________.
A) ammonia combining with oxygen to form urea
B) adequate fat calories to provide adequate ATP formation
C) adequate essential amino acids
D) excessive amounts of protein in the diet
Answer: D

…

When a person’s hypothalamic thermostat is set to a higher level and the actual body temperature is below that level, the person may ________.
A) pant
B) shiver
C) perspire heavily
D) exhibit vasodilation of skin vessels
Answer: B

…

Glucose can be obtained from ________.
A) lipogenesis
B) triglyceride anabolism
C) glycogenolysis
D) protein anabolism
Answer: C

…

Which of the following is not a function of LDLs?
A) make cholesterol available to tissue cells for membrane or hormone synthesis
B) regulate cholesterol synthesis in tissue cells
C) influence cholesterol synthesis in tissue cells
D) transport cholesterol from the peripheral tissues to the liver
Answer: D

…

Which of the following best defines negative nitrogen balance?
A) It is a condition usually caused by having a diet low in fish and meat.
B) Protein breakdown exceeds protein synthesis.
C) It occurs when amino acids are broken down by liver enzymes and carried to the
bloodstream.
D) A negative nitrogen balance is normal and is a way of maintaining homeostasis.
Answer: B

…

The Krebs cycle produces ________ ATP molecules per glucose molecule by
substrate-level phosphorylation.
Answer: two

…

Which nutritional state constitutes the period during and shortly after eating when nutrients are flushing into the bloodstream from the GI tract?
Answer: absorptive

…

Fat burning causes an accumulation of acetyl CoA, which the liver converts to ________. 109)
Answer: ketones

…

________ is controlled hyperthermia. 110)
Answer: Fever

…

The enzymes that catalyze oxidation-reduction reactions by removing hydrogen are 111)
specifically called ________.
Answer: dehydrogenases

…

The process of splitting glucose through a series of steps that produces two pyruvic acid 112)
molecules is called ________.
Answer: glycolysis

…

In the Krebs cycle, citric acid is followed by ________ acid. 113)
Answer: isocitric

…

Compare and contrast PKU and galactosemia.
Answer: In PKU, the tissue cells are unable to use the amino acid phenylalanine present in all
protein foods. The defect involves a deficiency of the enzyme phenylalanine
hydroxylase that converts phenylalanine to tyrosine. Galactosemia results from an
abnormality or lack of liver enzymes needed to transform galactose to glucose. Both can lead to brain damage.

…

Explain why the elderly more easily gain weight, even though they may actually eat very little.
Answer: The metabolic rate of the elderly declines steadily with age as skeletal muscles begin
to atrophy and activity usually declines. Even eating enough to maintain proper
nutrition, the metabolic rate is so slow that not all of the food is used for energy.

…

What are the four mechanisms of heat exchange and how are they defined?
Answer: (1) Radiation is the loss of heat as thermal energy. (2) Conduction is the transfer of heat between objects that are in direct contact with each other. (3) Convection is the process of replacing the warm air around the body with cooler air and thus removing body heat. (4) Evaporation cools by removing large amounts of heat as water changes state from liquid to gas.

…

Define amino acid pool and explain how the pool is maintained even though we excrete 117)
amino acids daily.
Answer: The amino acid pool consists of the body’s total supply of free amino acids needed to resynthesize body proteins. Even though a small amount of amino acids and proteins is lost daily in urine, these are replaced through diet. If they are not replaced, the amino acids resulting from tissue breakdown become a part of the pool.

…

Hypervitaminosis may have serious consequences. Which vitamin group, water or fat soluble, is most likely to be involved in such cases and why?
Answer: Fat-soluble vitamins are most likely involved in hypervitaminosis, because they are
stored in the body and excesses are not removed.

…

What is obesity, and what health problems accompany or follow its onset?
Answer: Obesity is a BMI (body mass index) greater than 30. Health problems accompanying or following obesity include a higher incidence of arteriosclerosis, hypertension,
coronary artery disease, and diabetes mellitus.

…

How is the postabsorptive state controlled and initiated?
Answer: The postabsorptive state is controlled by the interaction of the sympathetic nervous system and several hormones, especially glucagon. The trigger for initiating postabsorptive events is damping of insulin release, which occurs as blood glucose levels begin to drop. Insulin levels decline, and the insulin-induced cellular
responses are inhibited.

…

What is the significance of the fact that monosaccharides are phosphorylated immediately upon entry into cells?
Answer: Monosaccharides are phosphorylated immediately upon entry into cells so that entry into metabolic pathways is possible. Additionally, phosphorylation, to change the structure of glucose, allows the maintenance of a diffusion gradient for simple glucose. Phosphorylation also prevents glucose from leaving the cell.

…

Explain what happens to pyruvic acid if oxygen is not present in sufficient quantities to support the electron transport system.
Answer: When oxygen is not present in sufficient amounts, the NADH + H+ produced during glycolysis begins to unload its hydrogen "baggage" back onto pyruvic acid, reducing it. This addition of hydrogen atoms to pyruvic acid results in the production of lactic acid.

…

Define nitrogen balance. List three factors that might lead to negative nitrogen balance and three that might result in positive nitrogen balance.
Answer: Nitrogen balance is a state when the amount of nitrogen ingested in proteins equals the amount of nitrogen excreted in urine and feces. Factors leading to negative nitrogen balance, when protein breakdown exceeds the use of protein for building structural or functional molecules, include physical and emotional stress, poor-quality dietary protein, and starvation. Factors leading to positive nitrogen balance, when the rate of protein synthesis is higher than the rate of its breakdown
and loss, include the normal condition in growing children and pregnant women,
periods of rebuilding or repair following illness, and site-specific regeneration
following injury.

…

After chopping wood for about 2 hours, on a hot but breezy afternoon, John stumbled into the house and
immediately fainted. His T-shirt was wringing wet with perspiration, and his pulse was faint and rapid. Was
he suffering from heat stroke or heat exhaustion? Explain your reasoning and note what you should do to help
John’s recovery.
Answer: John was suffering from heat exhaustion due to excessive loss of body fluids (indicated by his wet
T-shirt); his low blood pressure; and cool, clammy skin. To help his recovery, he should be given fluid
and electrolyte replacement therapy and should be cooled down.

…

Harry is hospitalized with bacterial pneumonia. When you visit him, his teeth are chattering, his skin is cool
and clammy to the touch, and he complains of feeling cold, even though the room is quite warm. Explain his
symptoms.
Answer: Harry’s symptoms indicate a fever caused by his bacterial pneumonia. The white cells battling the
pneumonia release pyrogens that act directly on the hypothalamus, causing its neurons to release prostaglandins. The prostaglandins reset the hypothalamic thermostat to a higher temperature, causing the body to initiate Heat-promoting mechanisms. Vasoconstriction causes a decline of heat loss from the body surface, cooling of the skin, and shivering.

…

Hank, a 17-year-old high school student, suffered a heart attack during a recreational swim. An autopsy
revealed that he had had atherosclerosis and that his death had been caused by coronary artery disease. What
might have been the cause of this disease that usually strikes a person much older than Hank?
Answer: Hank suffered from a genetic disorder known as "familial hypercholesterolemia," a condition in which the LDL receptors are absent or abnormal, the uptake of cholesterol by tissue cells is blocked, and the
total concentration of cholesterol and LDLs in the blood is enormously elevated. Victims of the disease
usually die in adolescence of coronary artery disease.

…

A young athlete is admitted to the hospital with diarrhea, vomiting, bone and joint pain, hyperglycemia, and
tingling sensations. What is the problem?
Answer: When asked what he had been taking, the athlete confessed that he was taking megadoses of vitamins to
"help his body get stronger." Overdoses of vitamins A, D, E, C, B6, and niacin can be toxic.

…

The patient is a 28-year-old female with insulin-dependent diabetes. She developed viral gastroenteritis with
nausea and vomiting. She did not take her insulin and she became increasingly nonresponsive. Her husband
called 911 and she was taken to the emergency room. Her pulse rate was 128 and her respiratory rate was 28,
deep, and smelled fruity (Kussmaul breathing). Her urinary glucose and ketone levels were both 4+. Her pH
was dangerously low. Explain how the body attempted to compensate for the low serum pH.
Answer: The deep, rapid respirations were the body’s attempt to compensate for the extremely low pH.

…

) The patient is 45 years old and is obese. He states he has been on the Atkins diet and has lost 20 pounds. What
are the dangers inherent in following fad diets for quick weight loss?
Answer: Many fad diets are nutritionally unhealthy, particularly if they limit certain groups of nutrients. Some of
the liquid high-protein diets contain poor-quality protein and are actually dangerous.

…

What are the possible complications of obesity from a medical standpoint?
Answer: The obese have a higher incidence of arteriosclerosis, hypertension, coronary artery disease, and diabetes mellitus.

…

The patient is 52 years old and has a history of hypertension. His cholesterol level is 245. He states his job is
very stressful and he is recently going through a divorce. He admits to being overweight and has an inactive
lifestyle. His father died of a stroke at age 60. He is worried about having a heart attack and/or stroke and
wishes to change his lifestyle. The nurse encourages the patient to eat more fish. Explain why eating more fish
would be of benefit for this patient.
Answer: The omega-3 fatty acids in cold-water fish have a powerful antiarrhythmic effect on the heart and also make blood platelets less sticky, thus helping to prevent spontaneous clotting that can block blood
vessels and lower blood pressure.

…

1.1 Beta oxidation

Results in fatty acid chains being broken down

1.2 Glycolysis

Results in pyruvic acid

1.3 Krebs cycle

Initial metabolite is citric acid

1.4 Oxidative phosphorylation

Requires ATP synthase at end

2.1 Carbohydrate

Comprised of simple sugars; used as the major fuel source for cellular respiration

2.2 Protein

Comprised of amino acids; used to build structural components of cells as well as functional components (enzymes)

2.3 Lipids

Comprised of fatty acids and glycerol; should be 20%-35% of caloric intake

2.4 Minerals

Comprised of electrolytes; important as cofactors

2.5 Vitamins

Small organic molecules; important as coenzymes; fat-soluble forms are A, D, E, and K

3.1 Carbohydrates

Provide primary source of fuel for ATP synthesis

3.2 Lipids

Act as an accessory fuel; component of membranes

3.3 Proteins

Important structural material (keratin, collagen, etc.) and functional material (enzymes, etc.)

3.4 Vitamins

Most function as coenzymes; not used as structural components

3.5 Minerals

Incorporation into some body structures; used in conjunction with enzymes

3.6 Water

Solvent for chemical reactions in body

4.1 Vitamin A

Required for synthesis of photoreceptor pigments in vision; integrity of skin, mucosae, and normal bone; and tooth development

4.2 Vitamin E

Primarily an antioxidant preventing oxidative damage to cell membranes and atherosclerosis

4.3 Vitamin D

Enhances absorption of calcium; works in conjunction with hormones regulating calcium blood levels

4.4 Vitamin K

Essential for formation of clotting proteins; intermediate in electron transport; participates in oxidative phosphorylation

5.1 Vitamin C

Important in formation of connective tissues; antioxidant; conversion of tryptophan to serotonin; conversion of cholesterol to bile salts

5.2 Vitamin B1 (thiamine)

Acts as coenzyme in carbohydrate metabolism; required to transform pyruvic acid to acetyl CoA; oxidation of alcohol

5.3 Vitamin B2 (riboflavin)

Acts as hydrogen acceptor in electron transport (FAD and FMN); component of amino-acid oxidases

5.4 Niacin

Acts as hydrogen acceptor in electron transport (NAD) during glycolysis and Krebs cycle; inhibits cholesterol synthesis; peripheral vasodilator

5.5 Folic acid

Basis of coenzymes in formation of certain amino acids, choline, DNA, RBCs, and normal neural tube development in embryo

5.6 Vitamin B12

Functions as coenzyme in all cells; acts in synthesis of DNA; essential for erythrocyte division during RBC production

6.1 Calcium

Milk, milk products, leafy green vegetables, egg yolk, shellfish

6.2 Sulfur

Meat, milk, eggs, legumes

6.3 Potassium

Avocados, dried apricots, meat, fish, fowl, cereals, bananas

6.4 Sodium

Cured meats, sauerkraut, cheese

6.5 Magnesium

Milk, dairy products, whole grain cereals, nuts, legumes, leafy green vegetables

6.6 Phosphorus

Diets rich in proteins; milk, eggs meat, fish, poultry, legumes, nuts, whole grains

7.1 Glycolysis

Two molecules of pyruvic acid and two NADH + H+

7.2 Krebs cycle

Five carbon dioxide molecules and ten molecules of reduced coenzymes (NADH + H+ and FADH2)

7.3 Electron transport chain and oxidative phosphorylation

36 ATP and 12 H2O molecules

8.1 Glycolysis

Breakdown of glucose

8.2 Lipolysis

Breakdown of lipids

8.3 Gluconeogenesis

Production of glucose from a noncarbohydrate source

8.4 Lipogenesis

Triglyceride synthesis

8.5 Glycogenesis

Polymerization of glucose

8.6 Transamination

Removal of NH3

A major means for conserving heat is:

vasoconstriction of cutaneous blood vessels.

In glycolysis, glucose must be activated with the use of how many ATP molecules?

One
Five
Two
Three
Ten

Two

Most vitamins:

function as coenzymes in the body. Coenzymes help catalyze chemical reactions.

One function of vitamin A is to:

form visual pigments.

The hormone responsible for setting the basal metabolic rate is:

thyroxine

The site of electron transport is the:

mitochondrial inner membrane (cristae)

The thermoregulatory center is located in the:

hypothalamus

Which coenzymes are reduced in both glycolysis and the Krebs cycle?

NAD. NAD is derived from niacin

Which element below is considered a trace mineral?
Sodium
Chromium
Potassium
Chlorine
Phosphorus

Chromium is considered a trace mineral. Glucose cannot be metabolized properly without chromium.

Which lipoprotein contains high levels of cholesterol?

LDL is nearly half cholesterol.

A nutritionally incomplete protein lacks:

one of the essential amino acids needed by the body.

Most of the ATP produced during cellular respiration is produced by:

oxidative phosphorylation during electron transport. Most of the ATP produced during cellular respiration is produced by oxidative phosphorylation during electron transport.

A function of the liver during the post-absorptive state is to:

mobilize glucose reserves by glycogenolysis. The liver mobilizes glucose reserves quickly and efficiently to maintain blood sugar levels for about four hours during the post-absorptive state.

The hormone that controls essentially all events of the absorptive state is:

insulin. Rising blood glucose levels after a carbohydrate-containing meal act as a humoral stimulus that prods the beta cells of the pancreatic islets to secrete more insulin.

Which of the following factors makes it harder for an obese person to lose weight?

An increase in alpha receptors (the kind that favor fat accumulation) in fat cells
An increase in heat loss from the body that requires more food intake
An increase in taste receptors
An increase in metabolism that increases the appetite
An increase in thyroxine levels as fat levels accumulate

An increase in alpha receptors (the kind that favor fat accumulation) in fat cells Fat cells of overweight people sprout more alpha-receptors, making it easier for fat cells to accumulate fat.

Which of the following is the amount of energy the body needs to maintain life?

BMR The BMR is only the amount of energy required for "housekeeping" activites, which keep us alive.

Which of the following is a physiological response to hypothermia?

Shivering
Covering up with a blanket
Increasing physical activity
Drinking warm fluids

Shivering. A physiological response is one that occurs subconsciously and is internally monitored.

A kilocalorie is the amount of energy needed to:

move one kilogram of water one meter.
heat one kilogram of water one degree Fahrenheit.
amount of energy locked up in one kilogram of water
heat one kilogram of water one degree Celsius.

heat one kilogram of water one degree Celsius. A kilocalorie is the amount of energy needed to heat one kilogram of water one degree Celsius.

Essential nutrients refer to nutrients that are:

obtained from an outside source because the body cannot make them. "Essential" here means that these substances cannot be made in the human body.

Prolonged high protein intake can lead to:

loss of bone mass. Prolonged high protein intake would lead to a positive nitrogen balance

Which of the following substances is considered a provitamin?

Beta-carotene Vitamin D can be made in the skin and is not a provitamin. Beta-carotene is considered a provitamin because the body can convert it to vitamin A through digestion.

Which of the following fat-soluble vitamins is not stored in the body?

Vitamin K
Vitamin A
Vitamin E
Vitamin D

Vitamin K Vitamin E is a fat-soluble vitamin that is stored in the body.

The final product of glycolysis is:

two molecules of pyruvic acid, two molecules of NAD+, and a net gain of two ATP. Acetyl coenzyme A is produced in the Krebs cycle, not by glycolysis.

Cyanide acts as a poison by:

interfering with the flow of electrons in the electron transport chain. Cyanide acts as a poison by interfering with the flow of electrons in the electron transport chain.

During fasts lasting several weeks, blood glucose is maintained by:

gluconeogenesis. Fatty acids cannot be used to bolster blood glucose levels. During fasts lasting several weeks, blood glucose is maintained by gluconeogenesis by the kidney and liver.

A low-density lipoprotein would contain:

a high lipid content. The higher the percentage of a lipid in a lipoprotein, the lower the density.

The role of _____________ is to transport excessive cholesterol from peripheral tissue to the liver, where it is broken down and becomes part of bile.

high-density lipoproteins The role of high-density lipoproteins is to transport excessive cholesterol from peripheral tissue to the liver, where it is broken down and becomes part of bile.

The official medical measurement of obesity is the:

body mass index The official medical measurement of obesity is the body mass index.

___________ acts to suppress appetite by inhibiting _____, which is the most-powerful known appetite stimulant.

Leptin; neuropeptide Y Leptin acts to suppress appetite by inhibiting neuropeptide Y, which is the most-powerful known appetite stimulant.

Which of the following statements about a "redox" reaction is correct?

Coenzymes accept hydrogen. Enzymes do not accept hydrogen. In a "redox" reaction coenzymes accept hydrogen.

Ascorbic acid (vitamin C) is an antioxidant.

T

Conduction is the same as radiation heat loss.

F

Fermentation occurs when oxygen is NOT available.

T

In glycolysis, glucose is initially cleaved into three, two-carbon groups.

F

In order for amino acids to be converted into lipids, they must be deaminated.

T

Most required nutrients can be obtained by eating bread and meats.

F

Oxidative phosphorylation is coupled to chemiosmosis.

T

The role of oxygen in cellular respiration is to combine with carbon during the Krebs cycle.

F

When blood glucose levels fall, glucagon is released and causes glycogenesis.

F

Anabolism is a building process in which larger molecules are built from smaller ones, while catabolism is a tearing down process in which complex structures are degraded to simpler ones.

T

The Krebs cycle is the partial breakdown of pyruvic acid.

F

Before lipids can be metabolized, the fatty acids must undergo beta oxidation to be converted into two-carbon acetic acid fragments.

T

Gluconeogenesis occurs during cell respiration in the mitochondria.

F

The major function of HDL is to transport excess cholesterol from peripheral tissues to the liver.

T

Calcium is a mineral.

T