Chapter 7: Microbial Nutrition, Ecology, and Growth

_____ is the acquisition of chemical substances by organisms for use as an energy source or as building blocks of cellular structures.

Nutrition

A(n) _____ aerobe, or strictly aerobic organism, requires oxygen for survival.

Obligate

An organism that is unable to grow outside of a living host is referred to as a(n) _____ intracellular parasite.

Obligate

The function of micronutrients, or trace elements are: Components of cell structure Proper enzyme function Maintenance of protein structure Components of metabolic pathways

Proper enzyme function Maintenance of protein structure

Which term describes a microorganism that thrives and divides under refrigeration conditions?

Psychrophile

Which of the following detection methods rely on nucleic acids for detection?

RT-PCR

What term is used to describe organisms that decompose organic remains from dead organisms as an energy source?

Saprobe

Which of the following are important roles of water in cellular growth and metabolism? Chemical solvent DNA Synthesis Diffusion of wastes and nutrients Proper enzyme function Digestion of macromolecules Propulsion of flagella Antibiotic resistance Production of endospores

Chemical solvent Diffusion of wastes and nutrients Proper enzyme function Digestion of macromolecules

Microorganisms that use inorganic chemicals for energy and carbon dioxide for carbon are termed _____.

Chemoautotroph

Which microorganism uses inorganic chemicals for energy and carbon dioxide for carbon?

Chemoautotroph

Cells usually obtain their nutrients as: Pure elements Compounds Gases

Compounds

A(n) _____ can scan a culture of bacteria or a sample of blood and differentiate between blood cells.

Coulter counter Flow cytometer

_____ phase is when a bacterial cell is placed into a new environment and cell division is slow.

Lag

Put the phases of a normal population growth curve in order. Lag phase Stationary phase Death phase Log phase

1. Lag phase 2. Log phase 3. Stationary phase 4. Death phase

The viable plate method is based on the principle that each colony isolated represents _____ cell or colony-forming unit from the original sample.

1

Which set of number describe bacterial growth after the culture has acclimated to the medium's conditions? 1,2,4,8,16,32,64 1,2,3,6,12,24,48 1,2,3,4,5,6,7

1,2,4,8,16,32,64

A(n) _____ microbe requires only inorganic nutrients and carbon dioxide as a sole carbon source.

Autotrophic

What is the temperature range for Mesophilic microorganisms?

10C-50C

Because mesophilic bacteria have an optimal temperature of _____C (same as human body temp.), they are the largest group of medically important microorganisms.

37

The range of temperature of a Thermophilic microorganism is:

45C-80C

An _____ is an organism that prefers acidic pH (pH below 7).

Acidophile

_____ involves the complete breakdown of glucose to yield carbon dioxide, water, and energy in the form of ATP.

Aerobic respiration

An organism that does not use oxygen gas, but can survive and grow in its presence is referred to as a(n) _____ _____.

Aerotolerant anaerobe *These organisms will use oxygen if it is present, but do not require it.

_____ _____ do not use oxygen gas but are not affected by its presence.

Aerotolerant anaerobes

What name is used to describe a microbe which prefers environments greater than a pH of 7?

Alkalinophile

A sealed jar with a hydrogen gas pack can be use to cultivate: Psychrophiles Anaerobes Capnophiles Aerobes

Anaerobes

Photosynthesis that does not utilize or produce oxygen is referred to as _____ photosynthesis.

Anoxygenic

A _____-troph is an organism that uses the sun's light to provide the chemical energy to produce sugar for cellular respiration.

Auto

_____ are organisms which thrive in deep ocean depths.

Barophiles

A(n) _____ is an organism that prefers carbon dioxide levels higher than those present in the normal atmosphere.

Capnophile

A(n) _____is an organism that prefers carbon dioxide levels higher than those present in the normal atmosphere.

Capnophile

The element _____ is represented by the letter C in CHONPS.

Carbon

Which of the following are inorganic compounds? Carbon dioxide Nucleic acids Water Methane Proteins Carbohydrates Minerals

Carbon dioxide Water Minerals

Which of the following are explanations for the limited growth during the lag phase? Cells have not yet reached their maximum division rate A period of adjustment is required Numbers are often too low for accurate counting Cells have already reached their maximum division rate Cells are dying at a rapid pace

Cells have not yet reached their maximum division rate A period of adjustment is required Numbers are often too low for accurate counting

Which phase of bacterial growth is when more cells are dying than reproducing?

Death

The _____ _____ count is obtained using a procedure that involves counting the number of cells in a sample microscopically using a special calibrated slide with a premeasured grid.

Direct cell

Micronutrients (zinc, manganese) that are required by cells in small amounts are termed trace _____.

Elements

Any element or molecule that must be provided to an organism is called a(n) _____ nutrient.

Essential

Because cells cannot synthesize all 20 amino acids required for growth, these amino acids are termed _____ amino acids.

Essential

The log phase of a normal growth curve is also referred to as the _____ growth phase.

Exponential

Microbes are most susceptible to antimicrobial agents during which growth phase?

Exponential phase

A _____ anaerobe is capable of growing in aerobic and anaerobic conditions.

Facultative

_____ can grow in the cold and are able to cause food-borne illness, but are not true psychrophiles.

Facultative psychrophiles Psychrotrophs

True or False: A Coulter counter can differentiate between living and dead or gram-positive and gram-negative organisms.

False

True or False: A person shedding bacteria in the late stages of infection is more likely to spread it to others than is a person in the early or middle stages.

False

In binary fission, the doubling time of a particular microbial species is also known as its _____ time.

Generation

What term is used to describe the amount of time of a particular microbial species needs to divide?

Generation time

What term is used to describe a graphical representation of a change in population size over time?

Growth curve

What name is ascribed to bacteria which require or tolerate high concentrations of salt?

Halophile

A _____-troph derives both energy and carbon from organic compounds.

Hetero

A(n) _____-troph is an organism which must consume their energy from other organisms.

Hetero

Which organisms relies upon organic compounds for its carbon and energy needs?

Heterotroph

Organic compounds are the carbon and energy source for _____.

Heterotrophs

Which element is represented by H in CHONPS?

Hydrogen

Microorganisms which prefer extremely hot environments (80C-110C) are called _____.

Hyperthermophile

Examples of _____ nutrients include magnesium sulfate, ferric nitrate, sodium phosphate, carbon dioxide, and water.

Inorganic

Living organisms obtain nutrients from _____ and _____ sources.

Inorganic Organic

Which is FALSE regarding binary fission? Daughter cells are identical to each other It is a type of asexual reproduction Binary fission occurs only once in the life of a single cell Leads to genetic variation

Leads to genetic variation

Natural organic nutrients are usually the product of which of the following? Living organisms Fermentation Water Soil

Living organisms

Identify any condition which would be optimal for most human anaerobic pathogens. -23C Low to no oxygen present Near Ph7 -35C Oxygen rich location

Low to no oxygen present Near Ph7 -35C

_____ are chemical substances required in large quantities by cells, such as carbon or phosphate.

Macronutrients

The _____ temperature is the highest temperature at which an organism will grow.

Maximum

A(n) _____ is a type of chemoautotroph that produces methane from hydrogen gas and carbon dioxide.

Methanogen

Any chemical substance required in small quantities, such as a trace metal, is termed a(n) _____.

Micronutrient

What term is used to describe organisms that exist in environments near the pH of 7?

Neutrophiles

A _____ is an organism's biological role or its contribution to its community.

Niche

All of the adaptations an organism makes to its habitat is known as its _____.

Niche

Which element is represented by N in CHONPS?

Nitrogen

Which of the following are organic nutrients? Minerals Carbon dioxide Nucleic acids Water Methane Proteins Carbohydrates

Nucleic acids Methane Proteins Carbohydrates

When a normally nonpathogenic saprobe causes infection in a compromised host, it is referred to as a(n) _____ pathogen.

Opportunistic

The temperature at which a species shows the most rapid growth rate is known as the cell's _____ temperature.

Optimum

Molecules that contain a basic framework of carbon and hydrogen are called _____ nutrients.

Organic

_____ compounds make up nearly the entire dry weight of cells.

Organic

What term is used to describe a microbe which thrives hypertonic environments?

Osmophile

Organisms that have the ability to adapt to wide variations in solute concentration are referred to as _____.

Osmotolerant

_____ organisms are able to adapt to a wide range of solute concentrations.

Osmotolerant

Saprobes digest food particles _____ the cell. Inside Outside

Outside

The element _____ is represented by the letter O in CHONPS.

Oxygen

The atmospheric gases that most influence microbial growth are:

Oxygen Carbon dioxide

The two atmospheric gases that have the greatest impact on microbial growth are _____ and _____.

Oxygen Carbon dioxide

Photosynthesis that results in the production of oxygen is referred to as _____ photosynthesis.

Oxygenic

Organisms that derive nutrients from the living hosts are called _____.

Parasites

The element _____ is represented by the letter P in CHONPS.

Phosphorus

All living things absolutely require which of the following elements?

Phosphorus Hydrogen Nitrogen Carbon Oxygen

Any microbe that uses photosynthesis to feed is specifically referred to as a(n) _____.

Phototroph

Autotrophic microbes that use photosynthesis to derive their energy are classified as _____, while heterotrophs that oxidize chemical compounds are classified as _____.

Phototrophs, chemotrophs

Oxygenic photosynthesis occurs in which of the following organisms? Purple sulfur bacteria E.coli Plants Cyanobacteria Algae

Plants Cyanobacteria Algae

Autotrophs can generate energy from which of the following? Simple, non-living chemical reactions Consumption of other organisms Sun light Without any energy input

Simple, non-living chemical reactions Sun light

During which phase of growth does the number of new cells balance the number of declining cells?

Stationary phase

Which element is represented by S in CHONPS?

Sulfur

The energy source for phototrophs is the _____, while the energy source for chemotrophs is _____.

Sun, chemical compounds

Death usually occurs to microbes when which of the following conditions exists?

Temperature above maximum

Which type of microbes are a common contaminant of pasteurized or heated foods?

Thermoduric microbes *Thermophiles usually inhabit the soil and water and are not human pathogens.

True or False: 96% of the cell is composed of 6 elements.

True

True or False: Population growth can be calculated mathematically.

True

True or False: Proteins are organic macronutrients that can satisfy a heterotrophs need for carbon.

True *Proteins are organic molecules that contain carbon.

What term is used to describe the cloudliness of a broth culture?

Turbidity

The _____ plate method is based on the principle that each colony isolated represents one cell or colony-forming unit from the original sample.

Viable

Which of the following are the two most prevalent chemical components of a cell? Water Inorganic elements Protein Nucleic Acids

Water Protein