Deck 6: Microbial Nutrition and Growth

Question 1

The term photoheterotroph refers to an organism that ________.

A) uses CO₂ for its carbon source
B) utilizes inorganic compounds for its carbon needs
C) gets energy from sunlight
D) gets energy by metabolizing organic matter of dead organisms
E) does not need a carbon source

Answer 1

gets energy from sunlight

Question 2

Aerobic respiration is an example of ________.

A) photosynthesis
B) methanoheterophy
C) photoheterotrophy
D) chemoheterotrophy
E) photoautotrophy

Answer 2

chemoheterotrophy

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

Copper

Question 4

Organisms that feed on dead organisms for nutrients are called ________.

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

Question 5

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 outcompeted by natural flora
E) None of the choices are correct

Question 6

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

A) carbon
B) macronutrients
C) water
D) growth factors
E) trace elements

Question 7

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 8

What compound is the most abundant in a cell?

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

Question 9

Most of the dry weight of a microbial cell is from ________.

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

Question 10

Organisms called ________ live on or in the body of a host and cause some degree of harm.

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

Question 11

An important mineral ion that is a component of chloroplasts and stabilizer of membranes and ribosomes is ________.

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

Question 12

Calcium is required for bacteria because it ________.

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

Question 13

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 14

Microorganisms require large quantities of ________ for use in cell structure and metabolism.

A) elements
B) macronutrients
C) water
D) growth factors
E) trace elements

Question 15

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 16

An organism that uses CO₂ for its carbon needs would be called a(n) ________.

A) heterotroph
B) autotroph
C) chemoheterotroph
D) saprobe
E) halotroph

Question 17

The term chemoheterotroph refers to an organism that ________.

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

Question 18

The term photoautotroph refers to an organism that ________.

A) is a decomposer
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 19

An important mineral ion of the cytochrome pigments of cellular respiration is ________.

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

Question 20

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 21

Which of the following require the cell to use ATP?

A) Facilitated diffusion
B) Diffusion
C) Endocytosis
D) Osmosis
E) None of the choices are correct.

Question 22

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 23

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

A) be in a hypotonic solution
B) gain water
C) be in an isotonic solution
D) shrivel
E) None of the choices are correct.

Question 24

An organism with a temperature growth range of 45°C to 60°C would be called a(n) ________.

A) extremophile
B) thermophile
C) psychrophile
D) psychrotroph
E) thermoduric

Question 25

An organism that grows slowly in the cold but has an optimum growth temperature of 25° C is called a(n) ________.

A) extremophile
B) thermophile
C) psychrophile
D) psychrotroph
E) thermoduric

Question 26

Nutrient absorption is mediated by the ________.

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

Question 27

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, very 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 28

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 29

The toxic superoxide ion is converted to harmless oxygen by two enzymes, ________.

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

Question 30

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 31

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 32

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(n) ________.

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

Question 33

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

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

Question 34

Facilitated diffusion is limited by ________.

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

Question 35

Human pathogens fall into the group termed ________.

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

Question 36

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 37

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
E) None of the choices are correct

Question 38

Diffusion of water through a semipermeable membrane is called ________.

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

Question 39

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

A) hypertonic
B) hypotonic
C) isotonic
D) All of the choices are correct.

Question 40

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 41

A barophile would grow best in ________.

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

Question 42

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

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

Question 43

The production of antibiotics is a form of antagonism called ________.

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

Question 44

The E. coli that normally live in the human large intestines and produce vitamin K for the body to use would best be termed a ________ relationship.

A) parasitic
B) saprobic
C) commensal
D) mutualistic
E) None of the choices are correct.

Question 45

When microbes are in a 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

The phase of the bacterial growth curve in which the rate of cell division equals the rate of cell death is the ________.

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

Question 47

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

Question 48

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

Question 49

When microbes live independently but cooperate and share nutrients, it is called ________.

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

Question 50

The time interval going from a single bacterial 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 51

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 52

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

A) Blood agar
B) Thioglycollate
C) Sulfite polymyxin sulfadiazine
D) Sodium chloride
E) None of the choices are correct.

Question 53

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

Question 54

A halophile would grow best in ________.

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

Question 55

An organism that cannot tolerate an oxygen environment is a(n) ________.

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

Question 56

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

Question 57

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

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

Question 58

An organism that cannot grow without oxygen is a(n) ________.

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

Question 59

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

Question 60

An organism that respires using oxygen when it is present but can switch to an alternative anaerobic pathways when it is absent is a(n) ________.

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

Question 61

A Coulter counter can count viable cells as well as determine the size.

Question 62

Obligate saprobes can adapt to a living host.

Question 63

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

Question 64

The degree of turbidity in a culture correlates to the amount of cell growth.

Question 65

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

Question 66

A closed culture system is used to determine a population growth curve.

Question 67

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

Question 68

Bacterial biofilms stimulate the immune system differently than free (planktonic) bacteria.

Question 69

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

Question 70

Anaerobes can be cultured in a CO₂ environment.

Question 71

Which of the following reflects the stages of binary fission in the correct order?

A) Replication of the chromosome, formation of central protein band, septum divides daughter cells
B) Replication of the chromosome, septum divides daughter cells, formation of central protein band
C) Septum divides daughter cells, replication of the chromosome, formation of central protein band
D) Formation of central protein band, septum divides daughter cells, replication of the chromosome
E) Septum divides daughter cells, formation of central protein band, replication of the chromosome

Question 72

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

Question 73

Atoms and molecules are in constant, random motion. Movement of any molecule along its concentration gradient is termed ________, and movement of water in the same manner, across a selectively permeable membrane, is called ________.

A) diffusion; osmosis
B) osmosis; diffusion
C) hypertonic; hypotonic
D) isotonic; hypertonic
E) isotonic; osmosis

Question 74

After binary fission, daughter cells will differ genetically.

Question 75

Binary fission results in four daughter cells from one parent cell.

Question 76

The direct cell count, using a cytometer, can calculate viable cell numbers from a sample.

Question 77

Bacteria have an average generation time of 24 hours.

Question 78

For a physician, treating a biofilm infection in a patient poses a significant challenge compared to treating an infection with planktonic bacteria. This is due to the fact that ________.

A) the biofilm likely contains several different species of bacteria living in a thick, extracellular matrix that cannot be treated by routine antibiotic therapy
B) planktonic bacteria and biofilm bacteria activate the same genes
C) despite being a thick layer, the pH remains constant throughout the biofilm making the deep layers hard to penetrate
D) planktonic bacteria secrete quorum-sensing proteins that interfere with the actions of the antibiotic

Question 79

Organisms in a biofilm differ from planktonic bacteria in that ________.

A) biofilms typically contain multiple species of bacteria living in a complex, whereas planktonic bacteria are single, free-floating organisms
B) organisms in a biofilm secrete quorum-sensing chemicals to monitor the population; planktonic bacteria do not produce these chemicals
C) an organism in a biofilm will activate different genes compared to a planktonic organism of the same genus and species
D) organisms in a biofilm secrete extracellular materials to keep them anchored to a surface; these substances are not produced by free-floating bacteria
E) All of the choices reflect differences between biofilms and planktonic bacteria

Question 80

Lithoautotrophs use inorganic nutrients for carbon and energy sources.