Deck 7: Microbial Nutrition, Ecology, and Growth

Question 1

Which of the following is an important mineral ion of the cytochrome pigments used in cellular respiration?

A) iron
B) zinc
C) calcium
D) magnesium
E) potassium

Answer 1

A

Question 2

The methanogens, producers of methane gas, require environments that

A) have sunlight.
B) are very acidic.
C) have abundant oxygen and CO₂.
D) are extremely cold.
E) are anaerobic with hydrogen gas and CO₂.

Answer 2

E

Question 3

Which of the following is not a major element of a microbial cell?

A) copper
B) carbon
C) hydrogen
D) nitrogen
E) oxygen

Answer 3

A

Question 4

Which of the following is the largest component of the dry weight of a cell?

A) inorganic compounds
B) minerals
C) water
D) organic compounds
E) salts

Question 5

Aerobic respiration is an example of

A) photosynthesis.
B) methanoheterotrophy.
C) photoheterotrophy.
D) chemoheterotrophy.
E) photoautotrophy.

Question 6

What compound has the highest concentration in a cell?

A) CO₂
B) CH₄
C) H₂O
D) glucose
E) NH₃

Question 7

The term heterotroph refers to an organism that

A) uses CO₂ for its carbon source.
B) must obtain organic compounds for its carbon needs.
C) gets energy from sunlight.
D) gets energy by oxidizing inorganic compounds.
E) does not need a carbon source.

Question 8

Why do bacterial cells require calcium?

A) It stabilizes the cell wall.
B) It stabilizes the ribosomes.
C) It stabilizes the nucleoid.
D) It maintains cellular pH.
E) It makes strong bones.

Question 9

Organisms that feed on dead organisms for nutrients are called

A) saprobes.
B) parasites.
C) autotrophs.
D) lithoautotrophs.
E) phototrophs.

Question 10

An organism that uses CO₂ for its carbon needs and sunlight for its energy needs would be called a/an

A) heterotroph.
B) photoautotroph.
C) chemoheterotroph.
D) saprobe.
E) halotroph.

Question 11

The term phototroph refers to an organism that

A) uses CO₂ for its carbon source.
B) must obtain organic compounds for its carbon needs.
C) gets energy from sunlight.
D) gets energy by oxidizing chemical compounds.
E) does not need a carbon source.

Question 12

Which of the following is an important mineral ion that is a component of chloroplasts and stabilizer of membranes and ribosomes?

A) iron
B) zinc
C) calcium
D) magnesium
E) potassium

Question 13

The type of photosynthesis that does not produce oxygen

A) occurs in cyanobacteria.
B) does not require CO₂ as a reactant.
C) occurs in purple and green sulfur bacteria.
D) does not require sunlight.
E) occurs in algae and plants.

Question 14

Growth factors

A) are inorganic.
B) are synthesized by the organism.
C) contain elemental oxygen.
D) cannot be synthesized by the organism.
E) All of these choices are correct.

Question 15

The term autotroph refers to an organism that

A) uses CO₂ for its carbon source.
B) must obtain organic compounds for its carbon needs.
C) gets energy from sunlight.
D) gets energy by oxidizing chemical compounds.
E) does not need a carbon source.

Question 16

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

A) element
B) macronutrient
C) water
D) growth factors
E) trace element

Question 17

Which term refers to a nutrient that is required by a microorganism in large quantities for use in cell structure and metabolism?

A) element
B) macronutrient
C) growth factor
D) trace element

Question 18

An organic nutrient that cannot be synthesized by the organism and must be provided is called a/an

A) element.
B) macronutrient.
C) water.
D) growth factor.
E) trace element.

Question 19

Archaea as a group are not pathogens. This is because

A) they evolved without mammals.
B) mammals evolved special defenses against them.
C) mammalian hosts do not meet their environmental requirements.
D) they are out-competed by natural flora.

Question 20

The term chemotroph refers to an organism that

A) uses CO₂ for its carbon source.
B) must obtain organic compounds for its carbon needs.
C) gets energy from sunlight.
D) gets energy by oxidizing chemical compounds.
E) does not need a carbon source.

Question 21

The movement of substances from lower to higher concentration across a semipermeable membrane that must have a specific protein carrier and cell expenditure of energy is called

A) facilitated diffusion.
B) diffusion.
C) active transport.
D) osmosis.
E) endocytosis.

Question 22

Cultures of a bacterial species were incubated on the shelf of a refrigerator, out on a lab bench top, on the shelf of a 37°C incubator and on the shelf of a 50°C incubator. After incubation, there was no growth at 37°C and 50°C, slight growth out on the bench top and abundant growth at refrigeration. What term could be used for this species?

A) Halophile
B) Mesophile
C) Anaerobe
D) Psychrophile
E) Capnophile

Question 23

Which of the following microorganisms would find hypotonic conditions most detrimental?

A) bacteria
B) protozoa
C) fungi
D) algae
E) cyanobacteria

Question 24

Bacteria living in a freshwater stream that are moved to salty seawater would

A) now be in a hypotonic solution.
B) gain water as a result of the move.
C) now be in a isotonic solution.
D) shrivel as a result of the move.

Question 25

When whole cells or large molecules in solution are engulfed by a cell, this endocytosis is specifically termed

A) pinocytosis.
B) phagocytosis.
C) facilitated transport.
D) facilitated diffusion.
E) exocytosis.

Question 26

The use of energy by a cell to enclose a substance in its membrane by forming a vacuole and engulfing it is called

A) facilitated diffusion.
B) diffusion.
C) active transport.
D) osmosis.
E) endocytosis.

Question 27

Cultures of a bacterial species were incubated out on the incubator shelf, in an anaerobic jar and in a candle jar. After incubation there was moderate growth of cultures in the candle and anaerobic jars, but heavy growth of the culture on the incubator shelf. This species is a/an

A) aerobe.
B) anaerobe.
C) facultative anaerobe.
D) microaerophile.
E) capnophile.

Question 28

Microorganisms that live in severe habitats, such as very hot, acidic or salty environments, are called

A) thermophiles.
B) halophiles.
C) psychrophiles.
D) extremophiles.
E) barophiles.

Question 29

Which of the following terms refers to microorganisms that live in or on the body and cause harm?

A) mesophiles
B) thermophiles
C) commensals
D) pathogens
E) halophiles

Question 30

The term facultative refers to

A) the ability to exist in a wide range of conditions.
B) existing in a very narrow niche.
C) using chemicals for energy production.
D) using light for energy production.
E) using oxygen for metabolism.

Question 31

Which term refers to the diffusion of water through a semipermeable membrane?

A) facilitated diffusion
B) diffusion
C) active transport
D) osmosis
E) endocytosis

Question 32

The movement of molecules from an area of high concentration to an area of lower concentration is called

A) facilitated diffusion.
B) diffusion.
C) active transport.
D) osmosis.
E) endocytosis.

Question 33

Facilitated diffusion is limited by

A) ATP concentration.
B) the number of carrier proteins in the membrane.
C) size of the pores in the membrane.
D) osmotic pressure.
E) the size of the cell.

Question 34

In _____ conditions, the cell wall will help prevent the cell from bursting.

A) hypertonic
B) hypotonic
C) isotonic
D) mesotonic
E) All of these choices are correct.

Question 35

Which of the following require the cell to use ATP?

A) facilitated diffusion
B) diffusion
C) endocytosis
D) osmosis

Question 36

A microorganism that has an optimum growth temperature of 37°C, but can survive short exposure to high temperatures is called

A) an extremophile.
B) a thermophile.
C) a psychrophile.
D) a facultative psychrophile.
E) thermoduric.

Question 37

Contractile vacuoles are

A) used to expel excess water from cells.
B) found in bacterial cells.
C) important to certain organisms in hypertonic environments.
D) protein carriers in cell membranes.
E) used to bring solutes into a cell.

Question 38

The term obligate refers to

A) the ability to exist in a wide range of conditions.
B) existing in a very narrow niche.
C) using chemicals for energy production.
D) using light for energy production.
E) using oxygen for metabolism.

Question 39

Nutrient absorption is mediated by the

A) cell wall.
B) peptidoglycan layer.
C) proteins in the periplic space.
D) cell membrane.
E) nuclear membrane.

Question 40

The movement of substances from higher to lower concentration across a semipermeable membrane that must have a specific protein carrier but no energy expenditure is called

A) facilitated diffusion.
B) diffusion.
C) active transport.
D) osmosis.
E) endocytosis.

Question 41

An organism that can use gaseous oxygen in metabolism and has the enzymes to process toxic oxygen products is an)

A) aerobe.
B) obligate aerobe.
C) facultative anaerobe.
D) microaerophile.
E) obligate anaerobe.

Question 42

An organism that cannot tolerate any oxygen gas in its environment is an)

A) aerobe.
B) obligate aerobe.
C) facultative anaerobe.
D) microaerophile.
E) obligate anaerobe.

Question 43

The

A) parasitic
B) saprobic
C) commensal
D) mutualistic
E) coli that normally live in the human large intestines and produce vitamin K that the body uses would be best termed a _____ relationship.

Question 44

An organism that can exist in both oxygen and oxygen-free environments is an)

A) aerobe.
B) obligate aerobe.
C) facultative anaerobe.
D) microaerophile.
E) obligate anaerobe.

Question 45

When microbes in close nutritional relationship and one benefits but the other is not harmed, it is called

A) symbiosis.
B) satellitism.
C) commensalism.
D) mutualism.
E) synergism.

Question 46

Which location would best support the growth of a halophile?

A) acid pools
B) freshwater ponds
C) hot geyser springs
D) arid desert soil
E) salt lakes

Question 47

A microorganism that does not have catalase or superoxide dismutase would find it difficult to live in an environment with

A) carbon dioxide.
B) oxygen.
C) high salt.
D) temperatures above 37°C.
E) high acidity.

Question 48

An organism that cannot grow without oxygen is an)

A) aerobe.
B) obligate aerobe.
C) facultative anaerobe.
D) microaerophile.
E) obligate anaerobe.

Question 49

Which location would best support the growth of a barophile?

A) acid pools
B) deep oceans
C) hot geyser springs
D) arid desert soil
E) salt lakes

Question 50

A microaerophile

A) grows best in an anaerobic jar.
B) grows with or without oxygen.
C) needs normal atmospheric levels of oxygen.
D) requires a small amount of oxygen but won't grow at normal atmospheric levels.

Question 51

When microbes share a habitat, with each providing a necessary nutrient for the other, the relationship is called

A) syntrophy.
B) satellitism.
C) antibiosis.
D) antagonism.
E) autotrophy.

Question 52

The time interval from parent cell to two new daughter cells is called the

A) binary fission.
B) growth curve.
C) generation time.
D) death phase.
E) culture time.

Question 53

An organism with a temperature growth range of 45°C to 60°C would be called

A) an extremophile.
B) a thermophile.
C) a psychrophile.
D) a facultative psychrophile.
E) thermoduric.

Question 54

A change in one partner in a close relationship that leads to a change in the other partner is

A) symbiosis.
B) coevolution.
C) antibiosis.
D) mutualism.
E) synergism.

Question 55

The production of antibiotics is a form of amensalism called

A) symbiosis.
B) satellitism.
C) antibiosis.
D) mutualism.
E) synergism.

Question 56

An organism that grows slowly in the cold but has an optimum growth temperature of 32°C is called

A) an extremophile.
B) a thermophile.
C) a psychrophile.
D) a facultative psychrophile.
E) thermoduric.

Question 57

All of the following could find a location in or on body tissues suitable for growth except

A) psychrophiles.
B) anaerobes.
C) facultative anaerobes.
D) mesophiles.
E) capnophiles.

Question 58

What type of media is used to demonstrate oxygen requirements of microbes?

A) blood agar
B) thioglycollate
C) sulfite polymyxin sulfadiazine
D) sodium chloride

Question 59

Which two enzymes catalyze the steps converting the toxic superoxide ion to less harmful oxygen gas?

A) catalase and hydrogen peroxidases
B) superoxide dismutase and hydrogen peroxidase
C) superoxide dismutase and catalase
D) catalase and oxidase
E) superoxide dismutase and oxidase

Question 60

Which term describes human pathogens?

A) psychrophiles
B) thermophiles
C) halophiles
D) mesophiles
E) acidophiles

Question 61

Inorganic nitrogen must be converted to ammonia to be used by a cell.

Question 62

The phase of the bacterial growth curve during which microbial growth slows and the rate of multiplication equals the rate of cell death is the

A) lag phase.
B) log phase.
C) stationary phase.
D) death phase.
E) telophase.

Question 63

A saprobe with a cell wall will utilize extracellular digestion.

Question 64

In a commensal relationship, the commensal benefits but the cohabitant is neither harmed nor benefited.

Question 65

Bacteria have an average generation time of 24 hours.

Question 66

The time that it takes for a freshly inoculated agar culture to develop visible colonies is principally governed by that species'generation time.

Question 67

Whether an organism is an autotroph or heterotroph depends on its source of nitrogen.

Question 68

Facilitated diffusion and active transport require a carrier protein to mediate the movement across the pla membrane.

Question 69

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

A) lag phase.
B) log phase.
C) stationary phase.
D) death phase.
E) prophase.

Question 70

Obligate saprobes can adapt to a living host.

Question 71

Whether an organism is a phototroph or a chemotroph depends on its source of energy.

Question 72

Lithoautotrophs use inorganic nutrients for carbon and energy sources.

Question 73

When it is important to count the number of cells, determine cell size and differentiate between dead and live cells a ___ is used.

A) Coulter counter
B) flow cytometer
C) SEM
D) methylene dye indicator
E) plate count

Question 74

In the viable plate count method, a measured sample of a culture is evenly spread across an agar surface and incubated. Each _____ on the agar surface represents one _____ from the sample.

A) cell; cell
B) cell; colony
C) colony; cell
D) species; colony
E) generation; cell

Question 75

Saprobes do not need a carbon source for growth and metabolism.

Question 76

The phase of the bacterial growth curve in which newly inoculated cells are adjusting to their new environment, metabolizing but not growing is the

A) lag phase.
B) log phase.
C) stationary phase.
D) death phase.
E) prophase.

Question 77

The majority of microbes live and grow in habitats between pH 7 and 9.

Question 78

Most microorganisms on Earth can only live and survive in habitats that are similar to human body conditions.

Question 79

Anaerobes can be cultured in a CO₂ rich environment, as long as O₂ gas is excluded.

Question 80

Phosphorus is one of the major elements needed in larger quantities by microorganisms.