Microbio Final Prep - Exam 3

The phase of the bacterial growth curve where the rate of cell division equals the rate of cell death is the ____.

1. lag phase

2. log phase

3. stationary phase

4. death phase

stationary phase

The time interval going from a single Clostridium difficile parent cell to two new daughter cells is called the _____.

1. binary fission

2. growth curve

3. generation time

4. culture time

generation time

How many amino acids are used to make protein in bacteria?

1. 10

2. 20

3. 30

4. 40

20

Pseudomonas aerginosa, a common biofilm former on urinary catheters, cannot grow without oxygen, it is an example of a(n)___.

1. aerotolerant anaerobe

2. obligate aerobe

3. facultative anaerobe

4. microaerophile

5. obligate anaerobe

obligate aerobe

Campylobacter jejuni, a bacterium that can make people ill with diarrhea, required large quantities of ____ for use in metabolism and growth.

1. trace elements

2. macronutrients

3. micronutrients

4. growth factors

macronutrients

Which of the following is not a major element that makes up microbial cells?

1. Copper

2. Carbon

3. Hydrogen

4. Nitrogen

Copper

An organism that does not use oxygen in its metabolic pathways but can survive in its presence in a(n) ____.

1. aerotolerant anaerobe

2. obligate aerobe

3. facultative anaerobe

4. microaerophile

5. obligate anaerobe

aerotolerant anaerobe

Clostridium tetani does not have catalase or superoxide dismutase and therefore cannot live in an environment with ____.

1. carbon dioxide

2. oxygen

3. salt

4. temperatures above 25^o C

5. nitrogen

oxygen

All the following microbial groups could find a location in or on humans suitable for growth except ____.

1. psychrophiles

2. anerobes

3. facultative anaerobes

4. mesophiles

5. obliate aerobes

psychrophiles

In redox reactions, gain of electrons is ____.

1. phosphorylation

2. oxidation

3. fermentation

4. reduction

reduction

Which of the following molecules is not considered a polymer?

1. Carbohydrate

2. DNA

3. Protein

4. Lipid

Lipid

Microbes living on a slice of bread break down carbohydrates into ___ to use their metabolism.

1. glucose

2. amino acids

3. nucleotides

4. fatty acids

5. glycerol

Glucose

The term chemoheterotroph refers to an organism that ____.

1. uses CO₂ for its carbon source

2. must obtain inorganic compounds for its energy source

3. gets energy from sunlights

4. does not need a carbon source

5. gets energy by oxidizing organic compounds

gets energy by oxidizing organic compounds

An essential nutrient is any nutrient that ____.

1. is required for normal functioning that cannot be synthesized by the microbe

2. a microbe can synthesize and dies bit require from its diet

3. a microbe requires large quantities for growth

4. a microbe requires small quantities for growth

5. makes microbes grow faster

is required for normal functioning that cannot be synthesized by the microbe

Microorganisms living in biofilms use molecules to communicate via a process called ____.

1. quorum sensing

2. remote sensing

3. conjugation

4. bacterial therapy

5. microbial telepathy

quorum sensing

Halobacterium salinarum, a halophile grows best in ____.

1. acid pools

2. freshwater ponds

3. hot geyser ponds

4. acid, desert soil

5. salt lakes

salt lakes

Frozen shakes served in nursing homes and hospitals were recalled in February 2025 after being linked to the largest outbreak of listeriosis since 2011. Listeria monocytogenes, the causative agent of listerosis, is an example of a ____ due to its ability to grow at refrigerator temperatures.

1. psychedelic

2. thermophile

3. psychortoph

4. mesophile

5. thermophile

psychrotroph

In Mycobacterium tuberculosis, when a glucose molecule is completely oxidized in aerobic cellular respiration, the maximum number of ATP that can be granted is ____?

1. 2

2. 6

3. 24

4. 38

5. 100

38

During which phase of cellular respiration is the majority of ATP formed?

1. Krebs cycle

2. Glycolysis

3. Processing of pyruvic acid for the Krebs cycle

4. Electron transport

5. All phases produce the same number of ATP molecules

Electron transport

As electron carries shuttle electrons in the electron transport chain, the actively pump ____ into the outer membrane compartment setting up a concentration gradient called the proton motive force.

1. ATP

2. phosphate

3. hydrogen ions

4. oxygen

5. NADH

hydrogen ions

In E. Coli, the electron transport system is located in the ___.

1. cell membrane

2. mitochondria

3. chloroplasts

4. ribosomes

5. cytoplasm

cell membrane

Enzymes that are always present, regardless of the amount of substate, are ____.

1. apoenzymes

2. axoenzymes

3. constitutive enzymes

4. regulated enzymes

5. endoenzymes

constitutive enzymes

During aerobic cellular respiration in Micococcus luteus, the final electron acceptor is ____.

1. pyruvic acid

2. oxygen

3. nitrate

4. cytochrome c

5. FAD

oxygen

During competitive enzyme inhibition in Borrelia burgdorferi competitor molecules bind to the ____.

1. regulatory site to inhibit enzyme activity

2. active site to inhibit enzyme activity

3. active and regulatory site to inhibit enzyme activity

4. product to inhibit enzyme activity

active site to inhibit enzyme activity

Enzymes that hydrolyze lipids are called ___.

1. phosphotransferase

2. proteases

3. lipases

4. aminotransferases

5. DNase

lipases

Microorganisms require small quantities of ___ for enzyme function and maintenance of protein structure.

1. carbon

2. macronutrients

3. water

4. growth factors

5. trace elements

trace elements

Which of the following statements regarding glycolysis is false?

1. Glycolysis occurs without the need for oxygen

2. Glycolysis ends with the formation of pyruvic acid

3. Glycolysis is the first step of fermentation

4. Glycolysis uses CO₂ and H₂O as substrates

5. Glycolysis involves the reduction of NAD+

Glycolysis uses CO₂ and H₂O as substrates

The term photoautotroph refers to an organism that ___.

1. is a decomposer

2. must obtain organic compounds for its carbon needs

3. gets energy from sunlight

4. gets energy from oxidizing chemical compunds

5. does not need a carbon source

gets its energy from sunlight

Cultures of bacterial species were incubated in a refrigerator, on a lab bench, in a 37^o C incubator, and in a 50^o C incubator. After incubation, there was no growth at 37^o C and 50^o C, very slight growth on the bench and abundant growth at refrigeration. What term could be used to describe this bacterial species?

1. Halophile

2. Mesophile

3. Anerobe

4. Capnophile

5. Psychrophile

Psychrophile

Which of the following statements about anaerobic respiration is false?

1. Glycolysis is the first step in anaerobic respiration

2. Anaerobic respiration generates ATP

3. Anaerobic respiration utilizes an electron transport system

4. Aerobic respiration uses the same final electron acceptor as aerobic respiration

Aerobic respiration uses the same final electron acceptor as aerobic respiration

Most human pathogens fall into the group termed ___.

1. psychrophiles

2. thermiphiles

3. halophiles

4. acidophiles

5. mesophiles

mesophiles

The reactions of fermentation function to produce ___ molecules used in glycolysis.

1. pyruvic acid

2. NAD+

3. NADH

4. glucose

NAD+

The enzyme that allows some pathogenic bacteria and fungi to resist hydrogen peroxide, by converting toxic peroxide into harmless water oxygen, is called ____.

1. hydrogen peroxide

2. reactive oxygenase

3. superoxide dismutase

4. catalase

catalase

The phase for bacterial growth curve that shows the maximum rate of cell division is the ___.

1. lag phase

2. prophase

3. stationary phase

4. death phase

5. exponential phase

exponential phase

Storing food in brine is an effective way of preserving food because ____.

1. the high salt levels interfere with the enzyme activity of most microbes and inhibits their growth

2. the high salt levels make food less appealing to food spoilage bacteria

3. most food spoilage microbes don’t like salt

4. the high salt levels kill all microbes in food making it sterile and preventing spoilage

the high salt levels interfere with the enzyme activity of most microbes and inhibits their growth

All of the following statements are true except.

1. Enzymes can be reused in chemical reactions

2. Not all enzymes require cofactors

3. Enzymes active sites are substrate specific

4. Enzymes are not consumed or permanently altered by chemical reactions

5. Enzymes increase the activation energy required for a reaction to start

Enzymes increase the activation energy required for a reaction to start

Which of the following is not a product of microbial fermentation?

1. Pyruvate

2. CO₂

3. Vinegar

4. Alcohol

5. Hydrogen

Pyruvate

Enzymes that are produced only when a substrate is present are called ____.

1. exoenzyme

2. endoenzyme

3. constitutive enzymes

4. conjugated enzymes

5. induced enzymes

induced enzymes.

The following are all products of the TCA cycle in Vibro cholerae except ____.

1. carbon dioxide

2. ATP (or GPT)

3. sucrose

4. NADH and FAHD₂

Sucrose

Catabolic reactions are coupled with ATP ____, whereas anabolic reactions are coupled with ATP _____.

1. synthesis; hydrolysis

2. hydrolysis; synthesis

3. amphilbolism; repression

4. demination; beta oxidation

hydrolysis; synthesis