Microbiology Chapter 5 and 6 homework PDF

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principles of microbiology...

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Chapter 5 In metabolism, energy that is not used

is given off as heat. is used to build up large compounds from smaller ones. is stored in the form of ATP. is used to break down large molecules into smaller ones. The reactions involved in producing larger compounds from smaller compounds is called

metabolism. anabolism. catabolism. Where does the energy required for anabolic reactions come from?

Unused energy from metabolism Catabolic reactions Heat

The use of amino acids to make proteins

involves the production of ATP. is an example of anabolism. is an example of catabolism. is a completely efficient reaction.

Which of the following is an INCORRECT association?

electron transport: acetyl-CoA glycolysis: glucose 6-phosphate chemiosmosis: ATP synthase the Krebs cycle: oxaloacetic acid Which of the following pathways produces the most NADH and the least ATP?

Krebs cycle Calvin-Benson cycle glycolysis electron transport Which of the following is NOT an electron acceptor in anaerobic respiration?

oxygen SO42NO3CO32Where would you expect to find electron transport chains in a prokaryote?

Along the outer mitochondrial membrane Along the cell wall Free-floating in the cytoplasm Along the inner mitochondrial membrane Along the plasma membrane

According to the animation, which compounds provide electrons to the system?

NADH and FADH2 NADH Oxygen Water FADH2

According to the animation, what does oxygen get reduced to at the end of the electron transport chain?

Water Protons ATP Electrons NADH According to the animation, what does the electron transport chain do to the concentration of hydrogen ions (protons)?

The concentration of protons is higher outside the membrane than inside. The concentration of protons is lower outside the membrane than inside. The concentration of protons inside the membrane is equal to the concentration outside of the membrane.

The process of generating ATP using a proton gradient is referred to as

the electron transport chain. water damming. chemiosmosis.

Why is ATP required for glycolysis?

ATP is used to reduce NAD+ to NADH. ATP is used to convert PEP into pyruvic acid. ATP makes it easier to break apart glucose into two three-carbon molecules. ATP is used to convert DHAP into G3P.

Glycolysis literally means

sugar splitting. Embden-Meyerhof. energy producing. sugar producing. How many net ATPs can be made from one molecule of glucose in glycolysis?

Two Four One Six What carbon molecules remain at the end of glycolysis?

Pyruvic acid Glyceraldehyde 3-phosphate (G3P)

Glucose Dihydroxyacetone phosphate (DHAP)

Which of the following statements about glycolysis is true?

Glycolysis is the main source of NADH in the cell. Glycolysis is also called the Embden-Meyerhof pathway. All cells perform glycolysis. Glycolysis produces glucose.

What occurs at the bridge step?

The production of GTP The formation of succinyl CoA Decarboxylation of pyruvic acid The formation of oxaloacetate Based on the animation, how many electron carriers are reduced in the Krebs cycle only?

Six Five Three Four What is the function of GTP?

An energy carrier A scaffolding for carbon atoms

An oxidizer to produce CO2 An electron carrier

What is the fate of metabolites during respiration?

They are oxidized completely to carbon dioxide and water. They are oxidized completely to form pyruvic acid. They are rearranged to form GTP. They are reduced to from NADH and FADH2.

Which of the following statements concerning glycolysis is TRUE?

The glycolytic pathway is cyclical. Two NADH molecules are reduced during glycolysis. The first step of glycolysis involves oxidative phosphorylation. Ribulose 5-phosphate is an intermediate of glycolysis. Glucose is activated by substrate-level phosphorylation.

Pyruvic acid is a product of

the pentose phosphate pathway. the Krebs cycle. both fermentation and the Krebs cycle. fermentation. glycolysis.

Anaerobic bacteria may use ________ as the final electron acceptor during anaerobic respiration.

carbon dioxide only nitrate only sulfate only both nitrate and sulfate carbon dioxide, nitrate and sulfate

The electron transport chain provides the energy for

oxidative phosphorylation. substrate-level phosphorylation. photophosphorylation. beta-oxidation. anabolic reactions. How many ATP molecules can theoretically be produced from the NADH generated by the catabolism of a molecule of glucose during aerobic respiration?

38 4 36 34 30 Where is the majority of ATP generated in prokaryotic cells?

in the inner mitochondrial membrane in the cytosol

in the cytoplasmic membrane in the thylakoids on ribosomes

The conversion of pyruvic acid to acetyl-CoA can be described as ________, because a molecule of CO2 is produced as a by-product.

phosphorylation amination decarboxylation oxidation respiration

Although glycolysis requires an input of ATP, this pathway results in a net gain of two ATP; therefore it is a(n) ________ pathway.

reductive oxidative endergonic exergonic neither exergonic nor endergonic Which of the following is needed as a reactant for the first step of the citric acid cycle?

Succinyl CoA

Malic acid Oxaloacetic acid Citric acid

Where does the energy come from to power the formation of GTP?

ATP Water Succinyl CoA NADH

Which step involves the release of carbon dioxide?

The third and fourth steps The first and eighth steps The seventh step The second step

How many molecules of ATP can be generated from one molecule of NADH?

Four Two One Three

Which step(s) of the Krebs cycle does (do) not produce any usable energy?

The fifth step The first and eighth steps The second and seventh steps The sixth step The third step

Why does FADH2 yield less ATP than NADH?

Electrons from FADH2 cannot pump hydrogen ions out of the cell. FADH2 electrons enter the electron transport chain at a lower energy level. FADH2 binds directly to the ATP synthase enzyme. FADH2 electrons ultimately do not go to oxygen.

Which of the following can be used as a final electron acceptor for aerobic respiration?

Nitrate ion, sulfate ion and carbonate ion can all be used as a final electron acceptor. Sulfate ion Nitrate ion Molecular oxygen Carbonate ion

What is one difference between ubiquinones and cytochromes?

Ubiquinones cannot carry electrons; cytochromes can.

Ubiquinones are not made of protein; cytochromes are. Ubiquinones can only be reduced; cytochromes can only be oxidized. Ubiquinones can only be oxidized; cytochromes can only be reduced. How does the proton gradient help ATP synthase to make ATP?

Protons are not involved with this step; only electrons are. Protons move from inside the membrane to outside the membrane. Protons move along the membrane. Protons move from outside the membrane to inside the membrane.

Iron is considered an essential element for many bacteria. Based on the animation, how would lack of iron affect energy production of a bacterium?

Lack of iron would mean that most of the oxygen could be reduced to form water, improving energy yields. Lack of iron would not have any affect on this system. Lack of iron would mean lack of heme, and thus lower amounts of functioning cytochrome proteins. This would mean lower energy yields. Which of the following statements about fermentation is true?

It is an alternative way to return electron carriers to their oxidized state. It provides additional protons to allow the electron transport chain to continue. It is an alternative way for a cell to produce oxygen. It allows the electron transport chain to continue in the absence of oxygen.

What is the role of pyruvic acid in fermentation?

It becomes the final electron acceptor for the electron transport chain in the absence of oxygen. It takes the electrons from NADH, oxidizing it back into NAD+.

It provides the protons to be used in the electron transport chain. It is the organic acid end-product of fermentation.

What is the fate of the NAD+ newly regenerated by fermentation?

It is oxidized into carbon dioxide. It is converted into an organic acid. It returns to glycolysis to pick up more electrons. It is converted into ethanol.

Which of the following is an acid produced by fermentation?

Lactic acid Propionic acid Lactic acid and propionic acid Ethanol Pyruvic acid

What is the intermediate product formed by pyruvic acid during alcoholic fermentation?

Acetaldehyde Ethanol Formic acid Carbon dioxide

Lactic acid Glycolysis produces energy in which form?

NADH and ATP ATP NADH, ATP, and pyruvic acid NADH Pyruvic acid

Which step is the step for which glycolysis is named?

First Second Third Fourth Fifth Sixth What is meant by substrate-level phosphorylation?

Reduction of NAD+ to NADH Splitting of glucose into two pyruvic acid molecules Production of ATP using energy from a proton gradient

Production of ATP by transferring phosphates directly from metabolic products to ADP What is the driving force of energy production in steps 6 and 7?

The reduction of NAD+ to NADH The oxidation of three-carbon compounds The energy potential of a proton gradient The reduction of three-carbon compounds What is the net production of ATP in glycolysis?

Eight ATP Four ATP Two ATP Six ATP

Chapter 6

What enables the copied chromosomes to separate during binary fission?

The chromosomes are attached to different parts of cell membrane, which elongates and thus separates the chromosomes. The mitotic spindle drives the separation. The nuclear membrane dissolves. The septum splits the replicated chromosomes.

How long does it take for the daughter cells to initiate or start the next round of replication?

No time is needed -- the daughter cells cannot replicate further. After the cells have matured fully. No time is required -- they are ready to divide immediately after DNA replication and separation of the daughter cells is complete if conditions are right. 20 minutes

Put the following steps of bacterial replication in the correct order, starting from a parent cell. 1. 2. 3. 4.

Cell elongation Septum formation Chromosome replication Separation of daughter cells

2, 4, 3, 1 3, 1, 2, 4 1, 4, 3, 2 4, 3, 1, 2 3, 2, 1, 4

What would happen if the septum did not form during binary fission?

The parent cell would now have two copies of the chromosome. Nothing; the septum is not required for binary fission. The daughter cells would not be genetically identical. The chromosome could not replicate.

Starting with three cells, how many cells would result from three rounds of replication?

Six Nine Twelve Twenty-four Forty-eight Cannot be determined What results when a single bacterium reproduces?

One parent cell and a genetically different cell Two genetically unique daughter cells Two genetically identical daughter cells One parent cell and a genetically identical daughter cell

If you begin with six cells, how many cells would you have after three rounds of division?

Twelve cells Nine cells

Eighteen cells Twenty-four cells Forty-eight cells It is impossible to determine.

Which of the following is NOT a step in bacterial cell division?

Disappearance of nuclear envelope Replication of the genetic material Splitting apart of two new daughter cells Cell elongation Which step of binary fission is the reason for genetically identical daughter cells?

Elongation of the cell Replication of the bacterial chromosome Splitting of the two daughter cells There are four new daughter cells that result from one parental cell

Which of the following organisms would be most likely to contaminate a jar of pickles?

a neutrophile an obligate anaerobe a mesophile

an acidophile a thermophile A chemoheterotroph obtains its energy from __________ and its carbon from __________ sources.

redox reactions; inorganic light; inorganic light; organic redox reactions; organic A cell that uses an organic carbon source and obtains energy from light would be called a

photoautotroph. lithoautotroph. photoheterotroph. chemoautotroph. chemoheterotroph. An aquatic microbe that can grow only near the surface of the water is probably which of the following?

a chemotroph a lithotroph an anaerobe a heterotroph a phototroph A microbe that grows only at the bottom of a tube of thioglycollate medium is probably a(n)

aerotolerant anaerobe. obligate anaerobe. obligate aerobe.

microaerophile. facultative anaerobe. Ted heats some food just to boiling, and stores some of it immediately in a container which he places in the refrigerator. A week later he takes the food out and finds it has spoiled. The microbes responsible are probably

thermoduric. psychrophiles. hyperthermophiles. thermophiles. mesophiles.

The most commonly used isolation technique in microbiology laboratories is the __________.

pour-plate method streak-plate method enrichment culture viable plate count method Which type of media is used to prevent the growth of certain microbes while allowing the growth of others?

differential media enriched media synthetic media selective media

An epidemiologist is investigating a new disease and observes what appear to be bacteria inside tissue cells in clinical samples from victims. The scientist wants to try to isolate the bacteria in the lab. What culture conditions are most likely to be successful?

inoculation of EMB plates inoculation of a minimal medium broth culturing on blood agar plates inoculation of cell cultures incubation in an anaerobic culture system A clinical sample labeled as "sputum" was collected from

a piece of tissue. the central nervous system. the blood. the skin. the lungs. Microbes in the __________ phase of the microbial growth curve are most susceptible to antimicrobial drugs.

stationary lag death log Which of the following techniques is most useful for measuring microbial reproduction when the density of a microbial population is very small?

membrane filtration microscopic counts viable plate counts

turbidity The events of binary fission are I. the cell doubles in size II. the DNA is replicated III. the cell forms a septum IV. the cell separates from its offspring The CORRECT order of these events is

II, I, III, IV. II, III, I, IV. I, III, II, IV. I, II, IV, III. IV, I, III, II.

Which of the following toxic forms of oxygen is IMPROPERLY paired with the detoxifying enzyme or molecule?

hydroxyl radical: peroxidase peroxide anion: catalase singlet oxygen: carotenoids superoxide radical: superoxide dismutase Fermented foods such as sauerkraut or pickles are kept from spoiling by the effects of which of the following?

low oxygen levels pH temperature

hydrostatic pressure Which of the following represent the majority of pathogenic bacteria?

thermophiles psychrophiles mesophiles hyperthermophiles Which of the following does NOT happen above the maximum growth temperature of a microorganism?

Lipids become too fluid. Membranes become rigid and fragile. Proteins become denatured. Hydrogen bonds break....