Deck 4: Nutrition, Culture, and Metabolism of Microorganisms

Question 1

Allosteric enzymes have two important binding sites. These are the

A) allosteric and passive sites.
B) allosteric and effector sites.
C) active and allosteric sites.
D) active and inhibitory sites.

Answer 1

C

Question 2

The net gain of ATP per molecule of glucose fermented is

A) 1.
B) 2.
C) 4.
D) 8.

Answer 2

B

Question 3

The rising of bread dough is the result of

A) oxygen being released.
B) fermentation.
C) flour gaining electrons.
D) biotin production.

Answer 3

B

Question 4

From the standpoint of the microorganism, in glycolysis the crucial product is

A) not relevant because glycolysis is not a major pathway.
B) ATP; the fermentation products are waste products.
C) CO2; ATP is a waste product.
D) ethanol or lactate; ATP is a waste product.

Question 5

During electron transport reactions,

A) OH- accumulates on the outside of the membrane while H+ accumulates on the inside.
B) OH- accumulates on the inside of the membrane while H+ accumulates on the outside.
C) both OH- and H+ accumulate on the inside of the membrane.
D) both OH- and H+ accumulate on the outside of the membrane.

Question 6

Which statement is NOT true?

A) Most bacteria are capable of using ammonia as their sole nitrogen source.
B) Most available nitrogen is in organic forms.
C) Nitrogen is a major component of proteins and nucleic acids.
D) Some bacteria are able to use nitrates or nitrogen gas as their nitrogen source.

Question 7

Siderophores

A) help maintain osmotic balance in seawater microbes.
B) develop when errors in membrane synthesis occur.
C) bind iron and transport it into the cell.
D) are a key component in the cytochromes.

Question 8

The citric acid cycle

A) produces NADH as it progresses.
B) delineates the oxidation of pyruvate.
C) allows for the complete oxidation of glucose.
D) does all of the above.

Question 9

Regulation of an enzyme's activity occurs

A) before the enzyme is produced.
B) at any point on the enzymatic production pathway.
C) when the enzyme already exists in the cell.
D) during the production of the enzyme.

Question 10

Covalent modification of an enzyme often includes

A) addition or deletion of some small molecule.
B) rearrangement of the components of the enzyme proper.
C) binding of the enzyme to specific cytoplasmic ribosomes.
D) none of the above.

Question 11

The joining of an enzyme and substrate(s) depends on weak bonds, such as

A) hydrophobic interactions.
B) van der Waals forces.
C) hydrogen bonds.
D) all of the above.

Question 12

When writing half reactions,

A) the units are in joules for OE0'.
B) the pH of the reaction should be described because it cannot be assumed to be 7.0.
C) the reduction potentials are by convention described in terms of oxidation.
D) the final product(s) must be atomically balanced with the beginning substrate(s).

Question 13

The sum of all biosynthetic reactions in a cell is known as

A) anabolism.
B) synthatabolism.
C) catabolism.
D) metabolism.

Question 14

The process by which glucose is synthesized within the cell is

A) pentose.
B) gluconeogenesis.
C) peptidogenesis.
D) glycolysis.

Question 15

All organisms require the macronutrients

A) potassium, magnesium, and sodium.
B) calcium, potassium, and magnesium.
C) phosphorus, potassium, and magnesium.
D) phosphorus, potassium, and sodium.

Question 16

NAD+/NADH are involved primarily in reactions, while NADP+/NADPH are involved in reactions.

A) biosynthetic (anabolic) / energy- generating (catabolic)
B) energy- generating (catabolic) / both energy- generating (catabolic) and biosynthetic (anabolic)
C) energy- generating (catabolic) / biosynthetic (anabolic)
D) both energy- generating (catabolic) and biosynthetic (anabolic) / both energy- generating (catabolic) and biosynthetic (anabolic)

Question 17

A catalyst

A) changes the rate of the reaction but does not change the end amount of products.
B) changes both the rate of a reaction and the amount of the product that will be obtained as the reaction is completed.
C) makes possible otherwise impossible reactions.
D) increases the amount of reactants produced but does not change the rate.

Question 18

The portion of an enzyme to which substrates bind is referred to as the

A) catalysis site.
B) junction of van der Waals forces.
C) substrate complex.
D) active site.

Question 19

Which nutrient functions BOTH as an enzymatic cofactor and as a stabilizer of ribosomes and nucleic acids?

A) magnesium
B) calcium
C) phosphorus
D) potassium

Question 20

The macronutrient that comprises about 50% of the dry weight of a typical bacterial cell is

A) protein.
B) carbon.
C) nitrogen.
D) oxygen.

Question 21

If an oxidation reaction occurs, a reduction reaction must also occur because

A) Actually, reduction is not necessary if oxidation occurs.
B) electrons do not generally exist alone in solution.
C) half reactions are written that way.
D) that is what redox means.

Question 22

Which statement is TRUE?

A) Coenzymes bind tightly to their respective enzymes.
B) Coenzymes and prosthetic groups are technically not bound to their respective enzymes.
C) Coenzymes and prosthetic groups both bind tightly to their respective enzymes.
D) Prosthetic groups bind tightly to their respective enzymes.

Question 23

The Embden- Meyerhof- Pamas pathway is another name for

A) electron transport.
B) the citric acid cycle.
C) glycolysis.
D) NADH production.

Question 24

If OG0' is negative, the reaction is

A) endergonic and energy will be released.
B) endergonic and requires the input of energy.
C) exergonic and requires the input of energy.
D) exergonic and energy will be released.

Question 25

Prokaryotic polysaccharides are synthesized from

A) saturated fatty acids.
B) only one of two activated forms of glucose (UDPG and UDPG).
C) negative amino acids.
D) starch/glycogen complexes.

Question 26

The number of protons consumed by an ATPase per molecule of ATP formed is

A) 1.
B) 3- 4.
C) 6- 8.
D) 10.

Question 27

Activation energy is the energy

A) absorbed as OG0' moves from negative to positive.
B) required to transform all reactants into their reactive state.
C) given off as the products in a chemical reaction are formed.
D) sometimes referred to as catabolic energy.

Question 28

Which of the following groups is NOT membrane associated?

A) cytochromes
B) NADH dehydrogenases
C) flavoproteins
D) All of these are membrane associated.

Question 29

The roadblock created by the formation of a reduced electron carrier is overcome in fermentation by the

A) oxidation of NAD+ back to NADH.
B) reduction of NADH back to NAD+.
C) reduction of NAD⁺ back to NADH.
D) oxidation of NADH back to NAD⁺.

Question 30

Phosphorus in microorganisms can be found in

A) organic compounds.
B) inorganic compounds.
C) both organic and inorganic compounds.
D) neither organic nor inorganic compounds but in free elemental form in the cell.

Question 31

Two specific cellular reactions in a cell that require energy from the proton motive force are

A) biosynthesis and polymerization.
B) respiration and fermentation.
C) ion transport and flagellar rotation.
D) communication and metabolism.

Question 32

Chemolithotrophs are

A) heterotrophs.
B) phototrophs.
C) autotrophs.
D) organotrophs.

Question 33

For a carbon source, chemoorganotrophs generally use such compounds as

A) sunlight.
B) carbon dioxide.
C) triglycerides.
D) glucose.

Question 34

As each molecule of pyruvate traverses the citric acid cycle, how many molecules of CO2 are generated?

A) 1
B) 2
C) 3
D) 4

Question 35

Aseptic technique refers to

A) the microbial inoculum placed into a test tube or onto a Petri plate.
B) the prevention of contamination.
C) cleanliness in the laboratory.
D) the autoclave and other sterilizing procedures.

Question 36

Which statement is CORRECT?

A) Micronutrients are organic, but growth factors are metals.
B) Both micronutrients and growth factors are organic compounds essential for cell growth.
C) Both micronutrients and growth factors are essentially metals.
D) Micronutrients are metals, but growth factors are organic.

Question 37

In aerobic respiration, the final electron acceptor is

A) oxygen.
B) water.
C) ATP.
D) hydrogen.

Question 38

One example of an electron acceptor that can be used in anaerobic respiration is

A) water.
B) pyruvate.
C) NADH.
D) nitrate.

Question 39

Chemoorganotrophs use which of the following as an energy source?

A) organic compounds
B) inorganic compounds
C) both organic and inorganic compounds
D) either organic or inorganic compounds, depending on the environment

Question 40

The most important high- energy phosphate compound in living organisms is

A) RNA.
B) GTP.
C) ATP.
D) glucose.

Question 41

The tendency to become oxidized or reduced is expressed as the reduction potential in Volts.

Question 42

An enriched medium is a complex medium to which additional nutrients, such as
_ or , are added.

Question 43

The enzyme that catalyzes the conversion of the proton motive force into ATP is , a molecule that contains two major parts, _ and _. This reaction is known as .

Question 44

is the term used to describe the temporary combination of the enzyme and the reactant.

Question 45

Coenzymes increase the diversity of chemical reactions possible in a cell.

Question 46

In biochemistry, oxidations and reductions frequently involve the transfer of a(n) along with a(n) .

Question 47

If the name of a compound ends in "- ase," it is likely an enzyme.

Question 48

The term used to refer to all the chemical processes taking place within a cell is .

Question 49

are different enzymes that catalyze the same reaction but are subject to different regulatory controls.

Question 50

Controlling the activity of an enzyme is an inefficient use of the organism's energy.

Question 51

The enzyme responsible for splitting fructose 1,6- bisphosphate into two three- carbon molecules is .

Question 52

is the ability to do work.

Question 53

With regard to oxygen, glycolysis is a(n) process.

Question 54

Metabolic diversity in respiration and photosynthesis revolves around a common process, which is generation of a(n) .

Question 55

The process by which organisms synthesize the chemical substances of which they are composed is .

Question 56

The required or released to form a given molecule from its constituent elements is called .

Question 57

An enzyme that moves an amino group from one molecule to another is known as a(n)
.

Question 58

The Pasteur effect involves metabolically versatile microbes such as Saccharomyces cerevisiae that first perform metabolism. After this process, the yeast switches to
metabolism where two byproducts are and _ .

Question 59

Energy released as a result of oxidation- reduction reactions is usually conserved in the
.

Question 60

Two mechanisms for energy conservation in chemoorganotrophs are and
.

Question 61

Amino acids can be grouped into structurally related families that have similar biosynthetic steps.

Question 62

Most microorganisms have the same general nutritional requirements, so most microorganisms can grow on the same media.

Question 63

The theoretical maximum yield from each molecule of glucose during aerobic respiration is between 30 and 35 molecules of ATP.

Question 64

In electron transport systems, the electron carriers are membrane associated.

Question 65

Enzymes are biological catalysts.

Question 66

Inhibitors block both electron flow and the establishment of the proton motive force.

Question 67

Regulation of the amount of enzyme synthesized occurs only at the gene level.

Question 68

Energy can be measured in kilojoules.

Question 69

Feedback inhibition or covalent modification is generally sufficient for the regulation of gene expression.

Question 70

In substrate- level phosphorylation, ATP storage is depleted during the steps in catabolism of the fermentable compounds.

Question 71

Each molecule of NADPH+ yields 3 molecules of ATP.

Question 72

All prokaryotes require an organic carbon source.

Question 73

The energy released from the hydrolysis of coenzyme A is conserved in the synthesis of ATP.

Question 74

Heme prosthetic groups are involved in electron transfer with quinones.

Question 75

The third carbon of a glycerol backbone usually contains a polar group in the Bacteria and the
Eukarya.

Question 76

Whenever a bacterium undergoes fermentation, ethanol is a byproduct.

Question 77

Oxalacetate, generated in the citric acid cycle, is important both in the generation of certain amino acids and in the formation of phosphoenolpyruvate.

Question 78

A chemotroph uses chemicals for energy, while a phototroph uses light for energy.

Question 79

Inosinic acid is the precursor of the pyrimidines.

Question 80

AMP and methyl groups can play a part in covalent modification; ADP does not function in covalent modification.