chapter 26 metabolism and nutrition

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1) The sum of all of the biochemical processes going on within the human body at any given time is called
A) Anabolism.
B) Oxidative phosphorylation.
C) Metabolism.
D) Glycolysis.
E) Catabolism.

C) Metabolism.

2) Cells synthesize new organic components for which of the following reasons?
A) Growth and repair
B) To perform structural maintenance
C) To produce secretions
D) all of the above
E) A and B only

D) all of the above

3) During glycolysis
A) A molecule of glucose is converted into two molecules of pyruvic acid.
B) 6 molecules of ATP are produced.
C) More energy is used than is released.
D) NADH2 molecules attach to the cytochromes.
E) Carbon dioxide is produced

A) A molecule of glucose is converted into two molecules of pyruvic acid.

4) Inside the mitochondrion, each pyruvic acid molecule
A) Forms a molecule of citric acid.
B) Directly enters the electron transport system.
C) Is phosphorylated.
D) Attaches to NAD.
E) Loses a carbon atom.

E) Loses a carbon atom.

5) Most of the carbon dioxide of respiration is formed during
A) Electron transport.
B) The formation of pyruvic acid.
C) The TCA cycle.
D) Glycolysis.
E) The formation of water

C) The TCA cycle

6) In the electron transport chain
A) Oxidative phosphorylation takes place and ATP is formed.
B) Oxidized molecules gain energy at the expense of reduced molecules.
C) Coenzymes receive hydrogen atoms from NADH2 and FADH2.
D) all of the above
E) A and C only

E) A and C only

7) In glycolysis, each molecule of glucose that is metabolized releases how many molecules of ATP?
A) 2
B) 4
C) 30
D) 36
E) 38

B) 4(but 2 invested)

8) In the process of cellular respiration, each molecule of glucose that is metabolized yields enough energy to form ________ molecules of ATP.
A) 2
B) 4
C) 30
D) 37
E) 38

E) 38

9) During lipolysis
A) Lipids are converted into glucose molecules.
B) Triglycerides are converted into molecules of acetyl-CoA.
C) Lipids are metabolized to yield ATP.
D) Lipids are formed from excess carbohydrates.
E) Triglycerides are broken down into glycerol and fatty acids.

E) Triglycerides are broken down into glycerol and fatty acids.

10) All of the following are true of beta-oxidation, except that
A) It occurs in the mitochondria.
B) It requires coenzyme A, NAD, and FAD.
C) It yields large amounts of ATP.
D) Excess lipids are converted into glycogen molecules.
E) It is the process that breaks down fatty acids into two-carbon fragments that can be metabolized by the TCA cycle.

D) Excess lipids are converted into glycogen molecules.

11) Lipids
A) Are easily mobilized from their reserves.
B) Are difficult to store since they are not water soluble.
C) Provide energy for cells with modest energy demands and for skeletal muscle when energy demands are low.
D) Release less energy than an equivalent amount of glucose.
E) both B and C

C) Provide energy for cells with modest energy demands and for skeletal muscle when energy demands are low.

12) Lipogenesis generally begins with
A) Fatty acids.
B) Amino acids.
C) Glucose.
D) Succinyl-CoA.
E) Acetyl-CoA

E) Acetyl-CoA

13) Linoleic acid, linolenic acid, and arachidonic acid are examples of
A) vitamines.
B) transport proteins.
C) Essential amino acids.
D) Lipoproteins.
E) Essential fatty acids.

E) Essential fatty acids.

14) Lipoproteins containing triglycerides manufactured in the liver are transported to peripheral tissues and are called
A) Very high-density lipoproteins (VHDLs).
B) Low-density lipoproteins (LDLs).
C) Intermediate-density lipoproteins (IDLs).
D) High-density lipoproteins (HDLs).
E) Very low-density lipoproteins (VLDLs).

E) Very low-density lipoproteins (VLDLs).

15) Lipoproteins carrying mostly cholesterol and phospholipids from peripheral tissues to the liver are called
A) High-density lipoproteins (HDLs).
B) Low-density lipoproteins (LDLs).
C) Intermediate-density lipoproteins (IDLs).
D) Very high-density lipoproteins (VHDLs).
E) Very low-density lipoproteins (VLDLs

A) High-density lipoproteins (HDLs).

16) Catabolism of amino acids requires vitamin
A) A.
B) B12.
C) B6.
D) C.
E) Niacin.

C) B6

17) In transamination, the amino group of an amino acid is
A) Transferred to acetyl-CoA.
B) Transferred to a keto acid.
C) Transferred to a molecule in the glycolytic pathway.
D) Converted to urea.
E) Converted to ammonia

B) Transferred to a keto acid

18) The process of deamination produces
A) B vitamins.
B) Ammonia.
C) Keto acids.
D) Urea.
E) Acetyl-CoA

B) Ammonia.

19) Urea is formed in the
A) Small intestine.
B) Kidneys.
C) Liver.
D) Large intestine.
E) Stomach.

C) Liver.

20) For adults there are ________ essential amino acids.
A) 2
B) 6
C) 8
D) 11
E) 20

C) 8

21) Nucleotides from RNA
A) Can be used to synthesize proteins.
B) Cannot be used as a source of energy for the production of ATP.
C) Cannot be recycled.
D) Can provide sugars for glycolysis.
E) Are deaminated to form ammonia

D) Can provide sugars for glycolysis.

22) Purines
A) Provide sugars for the TCA cycle.
B) Can be used to form proteins.
C) When degraded produce urea.
D) Are readily catabolized in glycolysis.
E) Are deaminated and excreted as uric acid.

E) Are deaminated and excreted as uric acid.

23) During the absorptive state
A) The liver forms glycogen.
B) Glucagon levels are elevated.
C) Adipocytes contribute fatty acids to the circulation.
D) Skeletal muscle breaks down glycogen.
E) both A and D

A) The liver forms glycogen.

24) During starvation
A) Carbohydrate utilization increases.
B) Gluconeogenesis accelerates.
C) There is a decline in circulating ketone bodies.
D) Structural proteins can be used as a potential energy source.
E) both B and D

E) both B and D

25) A balanced diet should
A) Include adequate substrates for the production of energy.
B) Contain adequate amounts of vitamins and minerals.
C) Provide essential amino acids and fatty acids.
D) all of the above
E) B and C only

D) all of the above

26) The nutrients that yield the most energy per gram when metabolized are
A) Nucleic acids.
B) Vitamins.
C) carbohydrates.
D) fats.
E) proteins.

D) fats.

27) The major cation in extracellular fluid that is essential for normal membrane function is
A) Sodium.
B) Iron.
C) Potassium.
D) Magnesium.
E) Calcium.

A) Sodium.

28) The major cation in cytoplasm that is essential for membrane function is
A) Iron.
B) Sodium.
C) Potassium.
D) Calcium.
E) Magnesium

C) Potassium.

29) The major anion in body fluids is
A) Bicarbonate.
B) Chloride.
C) Iodide.
D) Sulfate.

B) Chloride.

30) A cation that is essential for muscle contraction, nerve function, and blood clotting is
A) Magnesium.
B) Selenium.
C) Potassium.
D) Calcium.
E) Sodium.

D) Calcium.

31) An ion that is a necessary component of high-energy compounds and nucleic acids and a structural component of bone is the ________ ion.
A) phosphate
B) chloride
C) iodide
D) bicarbonate
E) sulfate

A) phosphate

32) A cation that acts as a cofactor for enzymes that are required for normal membrane function is
A) zinc.
B) magnesium.
C) potassium.
D) Calcium.
E) Sodium

B) magnesium.

33) A mineral that is a component of hemoglobin, myoglobin, and cytochromes is
A) Zinc.
B) Magnesium.
C) Iron.
D) Calcium.
E) Cobalt

C) Iron.

34) The mineral that is necessary for the proper function of the enzyme carbonic anhydrase is
A) Iodine.
B) Cobalt.
C) Zinc.
D) Selenium.
E) Iron.

C) Zinc.

35) A mineral that is a necessary cofactor for hemoglobin synthesis is
A) Silicon.
B) Cobalt.
C) Iodine.
D) Zinc.
E) Copper

E) Copper

36) The vitamin that plays a role in maintaining epithelia and is required for the synthesis of visual pigments is vitamin
A) A.
B) B.
C) C.
D) D.
E) E.

A) A.

37) The vitamin that is required for proper bone growth and for calcium absorption and retention is vitamin
A) A.
B) B.
C) C.
D) D.
E) E

D) D

38) The vitamin that prevents the destruction of vitamin A and fatty acids is vitamin
A) A.
B) B.
C) C.
D) D.
E) E.

E) E

39) The vitamin that is essential for the production of several clotting factors is vitamin
A) A.
B) C.
C) K.
D) B.
E) E.

C) K.

40) The vitamin that acts as a coenzyme in decarboxylation reactions is
A) Thiamine.
B) Riboflavin.
C) niacin.
D) cobalamin.
E) folacin.

A) Thiamine.(B1)

41) The vitamin that is a constituent of the coenzymes FAD and FMN is
A) Thiamine.
B) Cobalamin.
C) Riboflavin.
D) Folacin.
E) Niacin.

C) Riboflavin.(B2)

42) The vitamin that is a constituent of the coenzyme NAD is
A) Cobalamin.
B) Folacin.
C) Thiamine.
D) Niacin.
E) Riboflavin

D) Niacin.

43) A vitamin that plays the role of a coenzyme in amino acid and lipid metabolism is
A) Riboflavin.
B) Niacin.
C) Folacin.
D) Pyridoxine (B6).
E) Pantothenic acid.

D) Pyridoxine (B6).

44) The vitamin that is a constituent of coenzyme A is
A) Riboflavin.
B) Pyridoxine (B6).
C) Folacin.
D) Pantothenic acid.
E) Niacin.

D) Pantothenic acid.(B5)

45) The vitamin that is a coenzyme in amino acid and nucleic acid metabolism is
A) Folacin.
B) Vitamin K.
C) Pantothenic acid.
D) pyridoxine (B6).
E) vitamine C.

A) Folacin.

46) Factors that influence an individual's BMR (basal metabolic rate) include all of the following, except
A) Body height.
B) Body weight.
C) Genetics.
D) Age.
E) Sex.

A) Body height.

47) When the temperature of the preoptic center exceeds its thermostat setting,
A) Peripheral vasoconstriction occurs.
B) Tidal volume increases.
C) Integumentary blood flow increases.
D) Sweat glands are inhibited.
E) both B and C

E) both B and C

48) All of the following occur when the temperature of the preoptic nucleus drops below acceptable levels, except that
A) Blood returning from limbs is shunted to deep veins.
B) Epinephrine levels rise.
C) Nonshivering thermogenesis occurs.
D) Blood flow to the skin increases.
E) Shivering thermogenesis occurs.

D) Blood flow to the skin increases.

49) Most heat is lost from the body through the process of
A) Radiation.
B) Evaporation.
C) Convection.
D) Conduction.
E) Concentration

A) Radiation.

50) Reactions within ________ provide most of the energy needed by a typical cell.
A) the mitochondria
B) cytoplasm
C) the endoplasmic reticulum
D) the cell wall
E) none of the above

A) the mitochondria

51) Cells expend energy because of their need to
A) Secrete.
B) Contract.
C) Expand.
D) Grow.
E) all of the above

E) all of the above

52) Cells must synthesize new organic compounds
A) To store nutrient reserves.
B) To support growth.
C) To perform structural maintenance or repairs.
D) To produce secretions.
E) all of the above

E) all of the above

53) In order for glycolysis to occur, ________ must be present.
A) NAD
B) appropriate cytoplasmic enzymes
C) glucose molecules
D) ATP and ADP
E) all of the above

E) all of the above

54) The ________ of the mitochondrion contains large-diameter pores that are permeable to ions and small organic molecules such as pyruvic acid.
A) outer membrane
B) inner membrane
C) powerhouse
D) cell wall
E) center

A) outer membrane

55) Each cytochrome contains
A) A protein.
B) A pigment.
C) A coenzyme.
D) both A and B
E) both B and C

D) both A and B

56) A malfunction of the thermoregulatory mechanisms caused by excessive fluid loss in perspiration is known as
A) Afebrile reaction.
B) Hemolytic reaction.
C) Heat exhaustion.
D) Frostbite.
E) Thermoneogenesis

C) Heat exhaustion.

57) A high uric acid level above 7.4 mg/dl can lead to the painful condition known as
A) Rheumatoid arthritis.
B) Lupus.
C) Anorexia.
D) Gout.
E) none of the above

D) Gout.

58) Many high school athletic teams host dinners the night before a big sporting event to feed the members of the team. Common meals include spaghetti and pastas. This is a common phenomenon termed
A) The Atkins diet.
B) Glycolysis reaction.
C) Carbohydrate craving.
D) Carbohydrate loading.
E) Overeating.

D) Carbohydrate loading.

59) The presence of ketone bodies in the urine is known as
A) Hematuria.
B) Ketonuria.
C) Uremia.
D) Polyuria.
E) Phenylketonuria

B) Ketonuria

60) A disease caused by the ingestion of excessive quantities of one or more vitamins is known as
A) Protein deficiency disease.
B) Hypervitaminosis.
C) Kwashiorkor.
D) Avitaminosis.
E) Carbohydrate loading.

B) Hypervitaminosis.

61) Although other nutrients can be broken down to provide substrates for the TCA cycle, ________ requires the least processing and preparation.
A) carbohydrate
B) protein
C) iron.
D) glycogen
E) both A and C

A) carbohydrate

62) In the human body, cholesterol is important because it
A) Waterproofs the epidermis.
B) Is a lipid component of all cell membranes?
C) Is the precursor of several steroid hormones and vitamin D3?
D) Is a key constituent of bile?
E) all of the above

E) all of the above

63) Which of the following individuals is most likely to have problems as a result of their cholesterol levels?
A) a 19-year-old with a normal LDL and a high total cholesterol level
B) a 25-year-old male with a total cholesterol of 190
C) a 50-year-old who doesn't exercise and has a total cholesterol of 200
D) a 45-year-old male with a total cholesterol of 225 who has had four family members die from coronary artery disease
E) both A and C

D) a 45-year-old male with a total cholesterol of 225 who has had four family members die from coronary artery disease

64) You are working in an outpatient clinic as a volunteer. Today, you are helping a nurse organize lab results from a recent cholesterol screening. The nurse teaches you that anyone with a total cholesterol level between 200 and 239 mg/dl should
A) Lose weight if overweight.
B) Modify his or her diet.
C) Have annual checkups.
D) Not worry about it if he or she exercises.
E) A, B, and C

E) A, B, and C

65) Glucocorticoids have which of the following effects on general peripheral tissues?
A) They decrease the use of glucose.
B) They increase the reliance on ketone bodies and fatty acids.
C) They increase use of glucose.
D) both A and B
E) both B and C

D) both A and B

66) Which of the following is a complement of glucocorticoids?
A) growth hormone
B) androgens
C) epinephrine
D) insulin
E) glucagon

A) growth hormone

67) The essential fatty acids that cannot be synthesized by the body, but must be included in the diet, are
A) HDLs and LDLs.
B) Cholesterol and glycerol.
C) Linoleic acid and linolenic acid.
D) Leucine and lysine.
E) all of the above

C) Linoleic acid and linolenic acid.

68) The lipoproteins that carry absorbed lipids from the intestinal tract to the bloodstream are the
A) chylomicrons.
B) VLDLs.
C) LDLs.
D) HDLs.
E) none of the above

A) chylomicrons

69) When the body is relying on internal energy reserves to continue meeting its energy demands, it is in the
A) Starvation state.
B) Preabsorptive state.
C) Absorptive state.
D) Deprivation state.
E) Postabsorptive state

E) Postabsorptive state

70) In oxidative phosphorylation, energy for the synthesis of ATP is provided by
A) The oxidation of acetyl-CoA.
B) The movement of hydrogen ions through channels in the respiratory enzymes.
C) The breaking of the covalent bonds in glucose.
D) The splitting of oxygen molecules.
E) The combination of two atoms of hydrogen and one atom of oxygen to form water.

B) The movement of hydrogen ions through channels in the respiratory enzymes.

71) A drug that blocks the action of lipoprotein lipase would
A) Raise blood levels of VLDLs.
B) Interfere with fat digestion.
C) Provide more fatty acids for adipocytes.
D) Increase the synthesis of cholesterol by the liver.
E) Decrease the emulsifying action of bile

A) Raise blood levels of VLDLs.

72) Catabolism of protein is not a practical source of quick energy because of all of the following, except that
A) Extensive destruction of protein would threaten homeostasis at the cellular and organismal levels.
B) One of the by-products of protein catabolism is a toxin.
C) Proteins are more difficult to break apart than lipids or carbohydrates.
D) Most cells do not contain the enzyme necessary to break the peptide bonds.
E) The energy yield from protein is less than the yield from lipids.

D) Most cells do not contain the enzyme necessary to break the peptide bonds.

73) A diet that includes just enough carbohydrate and lipid to meet daily needs would
A) Not maintain homeostasis.
B) Be inefficient from an energy standpoint.
C) Be incomplete.
D) Be a potential cause of dehydration.
E) Be protein sparing.

E) Be protein sparing.

74) A growing child is in a state of
A) Negative nitrogen balance.
B) Nitrogen equilibrium.
C) Positive nitrogen balance

C) Positive nitrogen balance

75) Inadequate exposure to sunlight could result in decreased amounts of vitamin _____ in the body.
A) A
B) B12
C) C
D) D
E) E

D) D

76) Impaired fat absorption in the intestine would interfere with the absorption of
A) Vitamin B12.
B) Vitamin C.
C) Vitamin A.
D) Riboflavin.
E) Niacin.

C) Vitamin A.

77) Which of the following individuals would have the greater BMR?
A) a nursing mother 34 years old
B) a nonpregnant, non-nursing woman 34 years old
C) Neither would be greater.

A) a nursing mother 34 years old

78) Two individuals are the same age, sex, and ethnic background. While being tested for their BMR, Bill consumes 20 liters of oxygen/hour and Randy consumes 16 liters of oxygen/hour. Which of the two needs to consume more calories in order to maintain proper health and constant weight?
A) Randy
B) Bill
C) neither Bill nor Randy

B) Bill

79) Which of the following individuals would lose heat fastest in a cold room?
A) a child
B) an adolescent male
C) an adult woman
D) a newborn infant
E) an adult man

D) a newborn infant

80) Which of the following is false regarding brown fat?
A) is innervated by the sympathetic nervous system
B) functions in nonshivering thermogenesis
C) is found in infants
D) contains a rich vascular supply
E) is concentrated around visceral organs in the adult

E) is concentrated around visceral organs in the adult

81) Which of the following would lose heat faster?
A) an obese person
B) a tall thin person

B) a tall thin person

82) In a disease that causes the destruction of a large number of cells and their nuclei, it would not be unusual to see an elevation in the blood levels of
A) Ammonia.
B) Ketone bodies.
C) RNA.
D) Uric acid.
E) DNA.

D) Uric acid.

83) If you were in a desert without water, which nutrient would you like to have stored in your body in a large amount?
A) protein
B) complex carbohydrates
C) sugars
D) fat
E) amino acids

D) fat

84) Mary is 18 years old. She is severely underweight, her skin is dry, and there are signs of peripheral edema. Her heart rate and blood pressure are unusually low and she has trouble concentrating on things. She tells her physician that she believes she is 30 pounds overweight and that she needs to diet. Mary probably has
A) Phenylketonuria.
B) Gout.
C) Hepatitis.
D) Lactose intolerance.
E) Anorexia nervosa

E) Anorexia nervosa

85) On a tour of African countries, Don contracts a bad case of traveler's diarrhea. Because he can't eat very much, his body starts to use energy sources other than carbohydrates. This would result in
A) Increased gluconeogenesis in the liver.
B) Ketosis and an increased blood pH.
C) Decreased levels of urea in the blood.
D) all of the above
E) B and C only

A) Increased gluconeogenesis in the liver.

86) Wally decides to go on a hunger strike to further one of his favorite causes. After 7 days of nothing but water you would expect to observe
A) Elevated levels of glucocorticoids.
B) Decreased respiratory minute volume.
C) Elevated blood pH.
D) Elevated levels of insulin.
E) Decreased urine output.

A) Elevated levels of glucocorticoids.

87) The process of synthesizing glucose from lipids, amino acids, or other carbohydrates is called ________.
A) Gluconeogenesis
B) Glycogenesis

A) Gluconeogenesis

88) The process of glycogen formation is known as ________.
A) Gluconeogenesis
B) Glycogenesis

B) Glycogenesis

89) Unsaturated fatty acids that are necessary for proper health but cannot be synthesized by the body are called ________.
A) essential fatty acids
B) Chylomicrons

A) essential fatty acids

90) ________ are lipoproteins that are formed in the intestine to carry lipids into circulation.
A) Chylomicrons
B) intermediate-density lipoproteins (IDLs)
C) low-density lipoproteins (LDLs)

A) Chylomicrons

91) Lipoproteins that contain smaller amounts of triglycerides and relatively more phospholipid and cholesterol than VLDLs are called ________.
A) Chylomicrons
B) intermediate-density lipoproteins (IDLs)
C) low-density lipoproteins (LDLs)

B) intermediate-density lipoproteins (IDLs)

92) Lipoproteins that contain large amounts of cholesterol that is being transported in peripheral tissues are called ________.
A) Chylomicrons
B) intermediate-density lipoproteins (IDLs)
C) low-density lipoproteins (LDLs)

C) low-density lipoproteins (LDLs)

93) ________ is an unhealthy state resulting from inadequate intake of one or more nutrients that becomes life-threatening as the deficiencies accumulate.
A) Malnutrition
B) Good nutrition

A) Malnutrition

94) A (n) ________ contains all of the ingredients necessary to maintain homeostasis.
A) Balanced diet
B) Undernutrition
C) over nutrition

A) Balanced diet

95) A (n) ________ contains all of the essential amino acids.
A) Complete protein
B) Incomplete protein

A) Complete protein

96) A (n) ________ is deficient in one or more of the essential amino acids.
A) Incomplete protein
B) Complete protein

A) Incomplete protein

97) ________ are inorganic ions released through the dissociation of electrolytes.
A) Minerals
B) Vitamins
C) amino acids

A) Minerals

98) The energy content of a material can be measured by a device called a (n) ________.
A) Calorimeter
B) Fat meter
C) Glucose meter

A) Calorimeter

99) The unit of measurement used for the energy content of food is the ________.
A) Calorie or kilocalorie
B) Centimeter
C) Calorimeter
D) Meter

A) Calorie or kilocalorie

100) The ________ represents the minimum resting energy expenditures of an awake, alert individual.
A) Basal metabolic rate
B) Resting metabolic rate
C) Metabolic rate

A) Basal metabolic rate

101) ________ is the homeostatic process that allows us to maintain a constant body temperature.
A) Thermoregulation
B) Calorie regulation
C) Metabolic regulation
D) Neural regulation

A) Thermoregulation

102) ________ is the direct transfer of heat energy from one object to another.
A) Conduction
B) Convection
C) Evaporation
D) radiation

A) Conduction

103) ________ is the transfer of heat energy to air.
A) Convection
B) Conduction
C) Evaporation
D) radiation

A) Convection

104) ________ is the loss of heat energy by vaporizing water.
A) Evaporation
B) Conduction
C) Convection
D) radiation

A) Evaporation

105) ________ is the most important mechanism for the generation of ATP.
A) Oxidative phosphorylation
B) Glycolysis
C) Lypolysis

A) Oxidative phosphorylation

106) Eating disorders are common among young adolescent girls. They result from a psychological problem that causes inadequate or excessive food consumption. Two major eating disorders are ________ and ________.
A) Anorexia; bulimia
B) Starvation; overeating
C) Gout; arthritis

A) Anorexia; bulimia

107) Eating a diet high in fats, oils, and sweets provides numerous ________ but deficient________.
A) Calorie; vitamins and minerals
B) vitamins and minerals; calorie
C) Calorie; glucose
D) Glucose; calorie

A) Calorie; vitamins and minerals

108) Mitochondria are not picky metabolizers. They will accept any molecules for energy production.
A) True
B) false

B) false

109) Catabolism within mitochondria provides the ATP needed to sustain cell functions.
A) True
B) false

A) True

110) In a condition known as gout, blood levels of uric acid are higher than normal. Since uric acid is not as soluble as urea, some of the uric acid will precipitate out in joint capsules, causing local inflammation, pain, and ultimately damage to the joint. Individuals with gout are frequently treated by altering their diet. How can this help?
Answer
Uric acid is produced when purine nucleotides are degraded. Since many people with gout cannot properly metabolize these nucleotides; they end up producing excessive amounts of uric acid. Keeping the level of purine nucleotides in the diet low would help reduce the levels of uric acid and the problems associated with gout.

...

111) What happens during protein catabolism? How is this related to nitrogen balance?
Answer
Protein catabolism is the breakdown of proteins into constituent amino acids. These amino acids can be either reused or broken down via deamination. Deamination removes the nitrogen group from the amino acid, which is then excreted from the body (nitrogen loss).

...

112) Why is the TCA cycle called a cycle? What substances enter the cycle, and what substances leave it?
Answer
The TCA reaction sequence is a cycle because the four-carbon starting compound (oxaloacetic acid) is regenerated at the end. Acetyl-CoA and oxaloacetic acid enter the cycle, and CO2, NADH, ATP, FADH2, and oxaloacetic acid leave the cycle.

...

113) Why is a starving person more susceptible to infectious disease than one who is well nourished?
Answer
During starvation the body must use fat and protein reserves to supply the energy necessary to sustain life. Some of the protein that is metabolized for energy is the gamma globulin fraction of the blood, which is mostly composed of Antibodies. This loss of antibodies, coupled with a lack of amino acids to synthesize new ones (as well as protective molecules such as interferon and complement proteins), renders an individual more susceptible than usual to contracting a disease and less likely to recover from it.

...

114) Anorexia nervosa is an eating disorder characterized by self-induced starvation. Individuals with this condition typically exhibit bradycardia, hypotension, and a decreased heart size. These problems can eventually lead to death from heart failure. How does anorexia cause such symptoms?
Answer
The response to anorexia is the same as in starvation. To supply the needed energy, the body utilizes reserves of fat and protein. Once the heart has exhausted its available fat reserves, it begins to break down contractible fibers to use the amino acids from the protein as an energy source. Eventually, the size of the heart and the force of cardiac contraction decrease. The weakened heart cannot contract as quickly as before, and Bradycardia results. The combination of Bradycardia and a decreased force of contraction contribute to hypotension. Ultimately, the heart will pump so inefficiently that it will not be able to serve the needs of the body's tissues; death will occur as the result of

...

115) The drug cholestipol binds bile salts in the intestine, forming complexes that cannot be absorbed. How would this drug affect cholesterol levels in blood?
Answer
Cholestipol would lead to a decrease in the plasma levels of cholesterol. Bile salts are necessary for the absorption of fats. If bile salts could not be absorbed, the absorption of fats namely, cholesterol and triglycerides would decrease. The result would be a decrease in fatty acids that could be used to synthesize new cholesterol. In addition, the body would have to replace the bile salts that are being lost with the feces. The drop in cholesterol levels would be further Enhanced because bile salts are formed from cholesterol.

...

In aerobic respiration carbohydrates are ultimately broken down into:

a.acetyl-CoA
b.CO2
c.O2
d.H2O
e.heat

b.CO2

Most ATP in eukaryotic cells is produced in the:

a.mitochondria
b.nucleus
c.cytoplasm
d.rough endoplasmic reticulum
e.peroxisom

a.mitochondria

Most ATP produced in aerobic respiration occurs in the process of:

a glycolysis
b.the formation of acetyl-CoA
c.the Krebs cycle
d.chemiosmosis
e.substrate-level phosphorylation

d.chemiosmosis

In glycolysis the most reduced compound formed is:

a.pyruvate
b.NAD+
c.lactate
d.O2
e.H2O

a.pyruvate

In glycolysis, the activation of glucose is accomplished by:
a.NADH
b.coenzyme A
c.ATP
d.CO2
e.O2

c.ATP

Which stage of aerobic respiration produces ATP and NADH and releases CO2?
a.glycolysis
b.Krebs cycle
c.electron transport chain
d.fermentation
e.none of the above

b.Krebs cycle

The high concentration of protons in the inner mitochondrial space relative to the mitochondrial matrix represents:
a.magnetic energy
b.kinetic energy
c.potential energy
d.photonic energy
e.none of the above

c.potential energy

As protons flow through the ______ , energy is released and exploited to combine ADP and inorganic phosphate to form ATP.
a.electron transport chain
b.outer mitochondrial membrane
c.cytochrome oxidase
d.ATP synthase
e.NADH

d.ATP synthase

In anarobic respiration, lactic acid is released into the blood from the skeletal muscle. When oxegen is available, most of the lactic acid is converted back to pyruvic acid and glocose in here:
a) liver
b) skeletal muscle
c) heart
d) lung
e) kidneys

a) liver

which is the healthiest ratio?
a) high HDL: low LDL
b) high LDL: low HDL
c) high LDL: Low chylomicron
d) high SFA: low HDL
e) high chylomicron: low LDL

a) high HDL: low LDL

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