Anatomy and Physiology Chapter 23 Mastering Questions
What is the correct general equation for cellular respiration?
C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + ATP energy
__________ refers to reactions in which large molecules are broken down into smaller molecules.
Catabolism
Trace the flow of electrons through the electron transport chain (the yellow arrows) in Focus Figure 24.8. Arrange the following electron acceptors in the order they participate in electron transport, from left to right.
Complex I or II ; Coenzyme Q ; Complex III ; Cytochrome c ; Complex IV ; Oxygen
Drag the appropriate labels to their respective targets: Involves the use of oxygen to pick up excess hydrogen and electrons.
Electron transport chain
T or F? A growing child is likely to exhibit negative nitrogen balance.
F
T or F? All athletes require diets high in protein and calories in order to perform and to maintain their muscle mass.
F
T or F? Beta oxidation is the initial phase of fatty acid oxidation, and it occurs in the cytoplasm.
F
T or F? Cellular respiration is an anabolic process.
F
Oxidative phosphorylation is the process by which ATP is formed as a result of the transfer of electrons from NADH or FADH2 to O2 (molecular oxygen) by a series of electron carriers. Where does oxidative phosphorylation take place in human cells?
Inner mitochondrial membrane
Which of the following is not true of beta oxidation?
It involves the anabolism of fats.
Drag the appropriate labels to their respective targets: Involves the removal of hydrogen, electrons, and CO2 from the substrate molecule.
Krebs cycle
__________ are considered "bad" cholesterol; high blood levels are believed to increase the risk of cardiovascular disease.
LDLs
Lipogenesis occurs when ________.
cellular ATP and glucose levels are high
Which food type is considered to be the most important for athletes to eat to improve performance?
complex carbohydrates
Prostaglandins play a role in ________.
control of blood pressure
Glycolysis is best defined as a catabolic reaction based upon the ________.
conversion of glucose into two molecules of pyruvic acid
Which of the choices below is not a fate of carbohydrate taken into the body?
conversion to a nucleic acid
The term basal metabolic rate reflects the ________.
energy the body needs to perform only its most essential activities
Which of the following nutrients yield the highest amount of energy per gram when metabolized?
fats
When ketone bodies are present in the blood and urine in large amounts, it usually indicates increased metabolism of ________.
fatty acids
Although both conditions share the common characteristic of elevated body temperature, hyperthermia is technically different from fever because ______.
fever is a condition in which there is a change in the body's temperature set-point
What is the outcome of ketosis?
metabolic acidosis
In what organelle would you find acetyl CoA formation, the citric acid cycle, and the electron transport chain?
mitochondrion
It is important to ensure that your diet is adequately rich in vitamins because ________.
most vitamins are coenzymes needed to help the body utilize essential nutrients
Which of the following is a common feature of the processes indicated by both letters D and E?
movement of hydrogen atoms associated with NADH
What process primes a molecule to change in a way that increases its activity, produces motion, or does work?
phosphorylation
Which of the following is a normal consequence of the activation of the heat-promoting center?
release of epinephrine
Which of the choices below is not a mechanism of heat production?
sweating
The "proton pumps" indicated in the figure are physically associated with ______.
the electron transport chain
During ketosis caused by inadequate ingestion of carbohydrates, ______.
the glycogen content of the liver is reduced
Many factors influence BMR. What is the most critical factor?
the ratio of surface area to volume (weight) of the body
One of the reasons why statins are effective in reducing the risk of cardiovascular disease is ______.
they decrease the incidence of cholesterol deposition in arterial walls
The amount of ________ produced is probably the most important hormonal factor in determining BMR.
thyroxine
Which hormone is called the "metabolic" hormone?
thyroxine
What is the primary function of cellular respiration - its end-purpose?
to generate ATP
The body's rate of kilocalorie consumption needed to fuel all ongoing activities is called the __________.
total metabolic rate
Transamination is the process whereby the amine group of an amino acid is ________.
transferred to a keto acid
Which of the following is not a function of LDLs?
transport cholesterol from the peripheral tissues to the liver
Which of the following is a characteristic of the electron transport chain (ETC)?
The ETC occurs in the mitochondria.
Which of the following statements is a false or incorrect statement?
The amino acid pool is the body's total supply of amino acids in the body's proteins.
Which statement describes glycolysis?
This process splits glucose in half and produces 2 ATPs for each glucose.
Which nutrients are the most important anabolic nutrients?
amino acids
In the liver, the amine group of glutamic acid is removed as ________ in the oxidative state.
ammonia
Gluconeogenesis is the process in which ________.
glucose is formed from noncarbohydrate precursors
In gluconeogenesis, during the postabsorptive state, amino acids and ________ are converted to glucose.
glycerol
Which of the following statements best describes complete protein?
must contain all the body's amino acid requirements for maintenance and growth
Which of the choices below happens during the absorptive state?
Anabolic processes exceed catabolic ones.
Which of the following is following is a true statement regarding the reactions indicated by the letters F and G?
Both reactions F and G involve the transfer of a phosphate group from an organic substrate to ADP.
Oxygen is consumed during which of the lettered processes?
C
T or F? Diets high in cholesterol and saturated fats tend to produce high HDL concentrations.
F
T or F? Leptin is a short-term regulator of food intake.
F
T or F? Most ATP in cellular respiration is generated in glycolysis.
F
T or F? Processes that break down complex molecules into simpler ones are anabolic.
F
T or 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
T or F? The major role of HDLs is to store energy in the form of fat.
F
T or F? The preferred energy fuel for the brain is fat.
F
T or 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
T or F? There are no complete proteins. All animal products should be eaten with plant material to make a complete protein.
F
T or F? Vitamins are inorganic compounds that are essential for growth and good health.
F
T or F? When blood glucose levels are low, the body begins to use more noncarbohydrate fuels for energy production. This process is called glucose activation.
F
Which energy-rich molecule produced by cellular respiration directly powers cell work?
ATP
Drag the labels onto the equation to identify the inputs and outputs of cellular respiration
Fuel: glucose Gas we inhale: O2 Gas we exhale: CO2 Water: H2O Energy packets that cells use to do work: ATP
Drag the appropriate labels to their respective targets: Glucose serves as the initial reactant.
Glycolysis
Drag the appropriate labels to their respective targets: Occurs in the cytosol of a cell.
Glycolysis
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?
He suffered from familial hypercholesterolemia.
Which of the following molecules is most directly involved in the transfer of "energy from food" to the "proton pumps" depicted in this figure?
NADH
Which of the following best defines negative nitrogen balance?
Protein breakdown exceeds protein synthesis.
If cyanide entered cells, the result would be ______.
a net gain of only 4 ATP molecules produced from each glucose molecule
Which of the following is NOT a pathway in the oxidation of glucose?
gluconeogenesis
Which nutrient molecule is the pivotal fuel molecule in the oxidative pathways?
glucose
The hyperglycemia that occurs during diabetes mellitus is accompanied by ______.
ketosis
Anabolism includes reactions in which ________.
larger molecules or structures are built from smaller ones
The process of breaking triglycerides down into glycerol and fatty acids is known as ________.
lipolysis
The primary goal during the postabsorptive state is to __________.
maintain blood glucose levels within an adequate range
Oxidation reduction reactions ________.
may involve the loss of hydrogen and electrons
T or F? Triglycerides and cholesterol do not circulate freely in the bloodstream.
T
__________ is a substance in food used by the body to promote normal growth, maintenance, and repair.
A nutrient
Which statement best describes the function of ATP synthase?
ATP synthase utilizes energy of the proton gradient to attach phosphate groups to ADP.
Heavy sweating can induce heat cramps due to ______.
All of the listed responses are correct.
Which of the following is a common feature of the both sets of reactions represented by the letters A and B in the figure?
Both include steps involving the oxidation of organic molecules.
How is the chemiosmotic process shown in the figure similar to secondary active transport (cotransport) of solutes discussed in Chapter 3 in the textbook?
Both processes use an electrochemical gradient to store energy.
Which of the following is correct?
Each FADH2 yields about 1 1/2 ATP via oxidative phosphorylation.
Which of the following statements regarding the electron transport chain is FALSE?
Each enzyme complex in the electron transport chain catalyzes the conversion of oxygen to water.
Drag the appropriate labels to their respective targets: Produces the most ATP.
Electron transport chain
__________ is the key hormone regulator of the absorptive state.
Insulin
The following figure represents a section of a mitochondrion. Drag and drop the + and - charges onto the figure to represent the charges after the proton gradient is established.
Intermembrane space: Positive (+) Mitochondrial matrix: Negative (-)
Focus your attention on the two phases of oxidative phosphorylation in Focus Figure 24.8. Sort the events into the appropriate phase of oxidative phosphorylation.
Phase 1: Generation of proton gradient ; Transfer of electrons ; Generation of water ; NADH donates e− ; O2 is final electron acceptor Phase 2: Flow of H+ into mitochondrial matrix ; Chemiosmosis ; Synthesis of ATP ; Phosphorylation of ADP Neither: Oxidation of food fuels
Select the correct statement about proteins.
Proteins will be used by most cells for ATP synthesis if insufficient carbohydrates are ingested.
T or 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
T or F? For use as fuel, all food carbohydrates are eventually transformed to glucose.
T
T or F? Ghrelin, produced by the stomach, is a powerful appetite stimulant.
T
T or 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
T or F? High levels of HDLs are considered good.
T
T or F? In order for amino acids to be oxidized for energy, the amine group (NH2) must be removed.
T
T or F? It would not be healthy to eliminate all fats from your diet because they serve a useful purpose in maintaining the body.
T
T or F? Peptides called NPY and AgRP are powerful appetite enhancers.
T
T or F? The amount of protein needed by each person is determined by the age, size, and metabolic rate of the person.
T
T or F? The body is able to form glucose from non-carbohydrate precursors.
T
T or F? The increased use of noncarbohydrate molecules for energy to conserve glucose is called glucose sparing.
T
T or F? The most abundant dietary lipids in the diets of most Americans are triglycerides.
T
T or F? The primary function of carbohydrates is energy production within cells.
T
Which statement describes the citric acid cycle?
This process produces some ATP and carbon dioxide in the mitochondrion.
Which statement describes the electron transport chain?
This process uses energy captured from electrons flowing to oxygen to produce most of the ATPs in cellular respiration.
Drag the labels onto the flowchart to indicate how food molecules reach the body's cells and fuel cellular respiration.
a. Eating food provides fuel and building blocks for your body. b. After food is broken down in the digestive system, it is transported to cells via the circulatory system. c. Fuel molecules are broken down further in glycolysis and the citric acid cycle (also called the Krebs cycle). d. ATP is produced with the help of the electron transport chain.
Which of the choices below is not a source of glucose during the postabsorptive state?
absorption of glucose from the GI tract
Glycogen is formed in the liver during the ________.
absorptive state
Where do the processes indicated by the letter C occur?
along the cristae of the mitochondria
Redox reactions __________.
are characterized by one substance gaining an electron while another substance loses an electron
Which of the following pathways act as a source for the electrons carried by the NADH and FADH2 molecules shown in this figure?
both A and B
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.
brain
The primary function of cellular respiration is to ________.
break down food molecules and generate ATP
Catabolism would be best described as a process that ________.
breaks down complex structures to simpler ones
Which of the following is NOT an end product of the Krebs cycle?
citric acid
Glycolysis occurs in the __________ of cells and is an __________ process.
cytosol; anaerobic
Which of the following would decrease body temperature?
dilation of cutaneous blood vessels
Which of the following food groups are considered good sources of complete proteins?
eggs, milk, yogurt, meat, and fish
Conditions that promote the oxidative deamination and energy use of amino acids include ________.
excessive amounts of protein in the diet
T or F? Except for lactose and some glycogen, the carbohydrates we ingest are mainly from animals.
f
The movement of H+ through the ATP synthase is best described as an example of ______.
facilitated diffusion
Proton pumps within the electron transport chain transport H+ ions ______.
from matrix to intermembrane space
Neurons and red blood cells rely exclusively on __________ to meet their energy needs.
glucose
The molecule that serves as the major source of readily available fuel for neurons and blood cells is ________.
glucose
Which of the following molecules is broken down in cellular respiration, providing fuel for the cell?
glucose
Glucose can be obtained from ________.
glycogenolysis
Which of the following does not occur in the mitochondria?
glycolysis
Which of the following processes takes place in the cytosol of a eukaryotic cell?
glycolysis
Select the correct sequence of steps as energy is extracted from glucose during cellular respiration.
glycolysis → acetyl CoA → citric acid cycle → electron transport chain
Which of the choices below describes the pathway of cellular respiration (the complete oxidation of glucose)?
glycolysis, Krebs cycle, electron transport chain, oxidative phosphorylation
Which brain region is the main integrating center for thermoregulation?
hypothalamus
Which of the following is represented by the "membrane" indicated in the figure?
inner mitochondrial membrane
Which hormone directs essentially all events of the absorptive state?
insulin
Which hormone directs essentially all the events of the absorptive state?
insulin
Minerals required by the body in moderate amounts include all but which of the following?
iron and selenium
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
Frostbite is LEAST likely to occur in the skin of a body region (e.g., abdominal region, finger region, etc.) that ______.
is closer to the heart than skin of a body region that is farther from the heart
Which term describes the breakdown of stored fats into glycerol and fatty acids?
lipolysis
Oxidative deamination takes place in the ________.
liver
Which of the following describes the event depicted on the right side of the figure?
oxidative phosphorylation
Which of the following mechanisms produces the most ATP during cellular respiration?
oxidative phosphorylation
In the case of a person who consumes a normal, balanced diet, proteins are essential to the body for all of the following except ________.
production of energy
Which of the following is the major role of leptin in the body?
protect against weight loss during nutritional deprivation
Which of the following is not an important function of the liver?
protein metabolism
The ingestion of which nutrient type results in the greatest food-induced thermogenesis?
proteins
When a person's hypothalamic thermostat is set to a higher level and the actual body temperature is below that level, the person may ________.
shiver
Which of the choices below is not a major route of heat exchange?
shivering
Metabolism includes both anabolism and catabolism. In hyperthyroidism, the metabolic rate is increased because ______.
the rate of exergonic reactions is increased
The term metabolism is best defined as ________.
the sum of biochemical reactions involved in building breaking down molecules
Which of the following events is NOT depicted in the figure?
transfer of electrons and hydrogen atoms from a food molecule to a coenzyme
The most abundant dietary lipids are ________.
triglycerides
When proteins undergo deamination, the waste substance found in the urine is mostly________.
urea
Which of the following is NOT an essential role of the liver?
urea disposal
Ammonia, which is a byproduct of protein metabolism, is converted to __________ primarily in the __________.
urea; liver
Heat-loss mechanisms do not include ________.
vasoconstriction of peripheral blood vessels
Which of the following is a water-soluble vitamin?
vitamin B
Which nutrients function as coenzymes and are needed in only small amounts?
vitamins
