Micro Chapter 6

An organism that benefits at the expense of another is called a ____________,

Parasite

Utilizes the tissues of a live host and an organic carbon source (example: pathogens)

Parasite

Which name is given to relationships between organism where one organism benefits at the expense to another organism?

Parasitism

Essential Nutrients

Any ingredients such as a certain amino acid, fatty acid, vitamin, or mineral that cannot be fomed by an organism, and must be supplied in the diet . A growth factor.

Facultative anaerobe

Describes an organism that can grow in the presence of oxygen and can detoxify it, but can also grow in the absence of oxygen

Microaerophile

Describes an organism that cannot grow at normal atmospheric oxygen concentrations, but does require a small amount of oxygen for growth

Aerotolerant anaerobe

Describes an organism that does not use oxygen, but can grow to a limited extent in the presence of oxygen

Obligate aerobe

Describes an organism that is unable to use oxygen and lacks the enzymes to detoxify oxygen, thus requiring the absence of oxygen for growth

Obligate aerobe

Describes an organism that requires oxygen for growth and has the enzymes to remove toxic by-products of oxygen metabolism

The movement of molecules along a concentration gradient by spontaneous random motion to achieve a uniform distribution is termed _______________________.

Diffusion

Enumeration of bacteria can be achieved by the ______cell count, in which a cell suspension in a chamber is viewed under the microscope.

Direct

Which of the following is true of passive transport Multiple Choice It uses the cell wall It requires a gradient It only moves water It includes endocytosi

It requires a gradient

Macronutrients

Large, molecular compounds assembled from smaller subunits, most notably biochemicals.

Most microbes prefer environments near or at a pH of

7

phagocytosis

A type of endocytosis in which the cell membrane actively engulfs large particles or cells into vesicles.

A bacterial pathogen that grows in the stomach would be best described as a(n) _____.

acidophile

A(n) _____ is an organism that prefers acidic pH.

acidophile

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

True

True or false: Nutrition is the aquisition of chemical substances by organisms for use as an energy source or as building blocks of cellular structures.

True

True or false: Oxygen is toxic to obligate anaerobes because these organisms lack the enzymes to degrade toxic products of aerobic metabolism.

True

True or false: Oxygen can be toxic for some microbes.

True For some microbes, oxygen can bind to important enzymes and disable critical metabolic activities.

The term______ describes the appearance of a cloudy broth culture.

Turbid

Isotonic

Two solutions having the same osmotic pressure such that, when separated by a semipermeable membrane, there is no net movement of solvent in either direction.

Which of the following types of radiation can damage microbes?

Ultraviolet and Ionizing

Which methods can be used to count bacterial populations without culturing on plates?

Using a flow cytometer Completing a direct cell count Analyzing turbidity of a broth

Lithoautotrophs

Bacteria that rely on inorganic minerals to supply their nutritional needs. Sometimes referred to as chemoautotrophs.

Bacteria reproduce by _________.

Binary fission.

What term describes a mixed community of microbes attached to the surface of one another

Biofilm

True or false: Survival in a changing environment is largely a matter of whether the genome can tolerate the alterations in the habitat.

False Enzymes are much more susceptible to denaturation from environmental changes.

Which best describes a parasitic relationship between microbe and host?

Flesh-eating bacteria on human skin

From which environment would you most likely observe growth of psychrophilic microorganisms?

Frozen food

Term used to describe the "best" temperature to support a microbe's growth

Optimal tempature

An _______nutrient is made of living things and composed of hydrogen and carbon.

Organic

Mutualism

Organisms living in an obligatory but mutually beneficial relationship.

Which term describes a microbe that grows in hypertonic environments.

Osmophile

__________ is a microorganism that thrives in a hypertonic medium.

Osmophile

_____is the diffusion of water across a selectively permeable membrane in the direction of lower water concentration.

Osmosis

During facilitated transportation molecules are moving across the membrane with the help of transport ________.

proteins.

Parasitism

symbiotic relationship in which one organism benefits at the expense of another organism

Which of the following macromolecules requires Nitrogen for biosynthesis?

-Nucleic acid -Proteins -ATP

Cells in the death phase that remain dormant and unresponsive to attempts to culture them are termed

. viable nonculturable

What environmental factors have an influence on microbial growth?

.Temperature Pressures Gases such as carbon dioxide and oxygen pH

Put the following phases in order for a normal bacterial growth curve. 1). Exponential 2). Log 3). Stationary 4). Death

1). Log 2). Exponential 3). Stationary 4). Death

Steps in binary fission of rod-shaped bacterium (Page 166 Figure 6.8)

1). a young cell. 2). Chromosome is replicated and new and old chromosomes move to different sides of cell. 3). Protein band forms in center of cell. 4). Septum formation begins. 5). When septum is complete, cells are considered divided. Some species will separate completely as shown here, while others remain attached, foring chains or doublets, for example.

Place the following steps in order to demonstrate your understanding of the viable plate count. 1). Take a sample from the broth and plate onto solid media. 2). Incubate all plates and count the colonies that develop. 3). Place a small number of cells into a sterile broth. 4). Incubate the broth for a set time period.

3,4, 1,2

Assuming you start with just one microbe and it could divide every 30 minutes, how many microbes would you have in 2 hours?

16

Identify the temperature range of thermophilic microorganisms.

45 celcius to 80 celcius

What is a capnophile?

A bacterium that requires carbon dioxide in higher levels than the atmosphere

Micronutrients

A chemical substance required in small quantities (trace metals, for example).

Viable Nonculturable State (VNC)

A description of a state in which bacteria are alive but are not metabolizing at an appeciable rate wand will not grow when inoculated onto laboratory medium.

Growth Curve

A graphical representation of the change in population size over time. This graph has four periods known as lag phase, exponential or log phase, stationary phase, and death phase.

Halophiles

A microbe whose growth is either stimulated by salt or require a high concentration of salt for growth.

Psychrophile

A microorganism that thrives at low temperature (0-20 C) with a temperature optimum of (0-15 C)

Osmophiles

A microorganism that thrives in a medium having high osmotic pressure.

Barophiles

A microorganism that thrives under high (usually hydrostatic) pressure.

Therophile

A microorganism tht thivs at a temperature of 50 C or higher .

Parasitism

A relationship between two organisms in which the host is shared in some way while the colonizer benefits.

Polymerase Chain Reaction

A technique that amplifies segments of DNA for testing. Using denaturation, primers, and heat-resistant DNA polymerase, the number an be increased several-million fold.

Active transport differs from diffusion in that energy in the form of ________ is required.

ATP and the proton motive force.

An ___________ is an organism that prefers alkaline pH (pH above 7).

Alkalinophile

What is a microaerophile?

An aerobic bacterium that requires oxygen at a concentration less than that in the atmosphere.

Symbiosis

An intimate association between individuals fro two species used as a synonym for mutualism.

Photoautotrophs

An organisim that utilizes light for its energy and carbon dioxide chiefly for its carbon needs.

Chemoautotrophs

An organism that upon inorganic chemicals for its energy and carbon dioxide for its carbon. aka chemolithotroph

Heterotrophs/autotrophs

An organisms that relies upon organic compounds for its carbon and energy needs.

Commensalism

An unequal relationship in which one species derives benefit without harming the other.

What word is used to describe organisms which do NOT use oxygen in their cellular respiration pathways?

Anaerobic

A relationship where the cells compete for survival in a common environment is known as:

Antagonism

What specific term is used to describe the production of antiobiotics from normal microbiota that leads to the protection of our bodies?

Antibiosis

What is an inorganic nutrient?

Atom or molecule containing elements besides carbon and hydrogen.

List and define four different terms that describe an organisms's sources of carbon and energy.

Autotroph--inorganic (ex: CO2 as carbon source)--prepare own food-- ex: 1). Phototroph---sunlight 2). Chemoautotrophs--inorganic matter*****Heterotrophs---_Organic material----1). Photoheterotroph---sunlight 2). Chemoheterotrophs---metabolic conversion of nutrients from other organisms. 3). Saprobe--metabolizing the organic matter of dead organisms. 4). Parasite ----It uses tissue and fluids of a living host.

What term is used to describe organisms that can generate their own food from inorganic compounds?

Autotrophs

What are the essential functions of a living membrane?

Block the entrance of large molecules Block the diffusion of proteins

A cell placed in a hypotonic environment, as illustrated in this image, will

C. swell with the influx of water

About 96% of the cell are composed of which elements?

CHOPKNS: Carbon, Hydrogen, Oxygen, Phosphorus, Nitrogen, Sulfer

List the essential nutrients of a bacterial cell

CHOPNS

Match each mineral ion with its role in a bacterial cell.

Calcium-stablizes the cell wall. Magnesium-Component of Chlorophll Zinc-Component of the DNA combining protein Sodium-Important for cell transport

Which enzyme converts hydrogen peroxide, formed in aerobic respiration, to water and oxygen?

Catalase

Uses simple inorganic compounds for energy and carbon dioxide for a carbon source (example: methanogens)

Chemoautotroph

Converts nutrients from other organisms into energy and uses an organic carbon source (example: protozoa)

Chemoheterotroph

Organisms that gt their energy from chemical compounds are called _________.

Chemotrophs

Turbid

Cloudy appearance of nutrient solution in a test tube due to growth of microbe population.

Which of the following are methods that count cells as they pass through a type of automated scanner? Turbidit measurement device Spectrophotometer Coulter counter Flow cytometer Direct cell count

Coulter counter and flow cytometer

Which methods count cells as they pass through an automated scanner?

Coulture Counter and Flow cytometer

Direct Cell Count

Counting total numbers of individual cells being viewed with magnification. Counting d colonies of organisms growing on a plate of media as a way to determine population size.

Death Phase

End of the cell growth due to lack of nutrition depletion of environment, and accumulation of wastes. Population of cells begins to die.

What describes a nutrient that be manufactured by an organism?

Essential

Bacterial growth occurs by the increase in cell population size such that each generation has twice as many cells as the previous generation. This growth pattern is termed _____.

Exponential

Which of the following are highly reactive, toxic byproducts of oxygen metabolism?

H2O2, O2-, and OH-

What are the highly reactive, toxic byproducts of oxygen metabolism?

H2O2, OH-, O2-

Which term describes bacteria that require or tolerate high concentrations of salt?

Halophile

Which term describes bacteria that requires or tolerate high concentrations of salt?

Halophile

Hypertonic

Having a higher concentration of solute than a reference solution.

Hypotonic

Having a lower concentration of solute than a reference solution

A solution that is __________ will cause the cell to lose water.

Hypertonic

If a cell is in a solution that is hypotonic relative to the cytoplasm, how will water move?

Into the cell by osmosis

Which of the following statements regarding parasites are true?

Intracellular parasites live within the cells Viruses are considered parasites

The term _________ describes 2 solutions that have the same osmotic pressure , such that when separated by a semi permereable membrane, there is no net movement of solvent in either direction.

Isotonic

Which of the following conditions would cause a bacterial culture in a exponential phase to shift to the stationary phase?

Loss of a nitrogen source and drop in temperature.

______________ are chemical substances, such as carbon or phosphate, that are required in large quantities by the cell.

Macronutrients

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

Macronutrients

Differentiate between macronutrients and micronutrients.

Macronutrients--required in lg quantities ex: Carbon, Hydrogen, Oxygen---play a role in structure and metabolism Micronutrients-required in sm quantities, ex: zinc, magnesium, and nickel----play a role in enzyme function and protein structure.

Because _____ bacteria have an optimal growth temperature in the range of human body temperature, they are the largest group of medically important microorganisms.

Mesophile

Trace elements

Micronutrients (zinc, nickel, and manganese) that occur in small amounts and are involved in enzyme function and maintenance of protein structure.

Chemoheterotrophs

Microorganisms that derive their nutritional needs from organic compounds.

Mesophiles

Microorganisms that grow at intermediate temperatures.

The _______temperature is the lowest temperature at which an organism will grow.

Minimum

active transport

Nutrient transport method that requires carrier proteins in the membranes of the living cells and the expenditure of energy.

Growth of a bacterial culture in a growth medium in a test tube is defined as a closed culture, meaning ________

Nutrients are limited and waste products are not removed.

An _______aerobe requires oxygen for survival.

Obligate

Choose the term that describes an organism that lacks superoxide dismutase and catalase enzymes to test your understanding of the role of these enzymes in microbial growth. Multiple Choice Capnophile Facultative anaerobe Obligate aerobe Obligate anaerobe Microaerophile

Obligate anaerobe

Choose all of the following that describe how biofilms become

Peripheral microbes die and protect more internal microbes from harm. Some biofilm microbes can produce protective compounds to stop antibiotic activity and therby protect the entire biofilm

Which of the following are essential functions of the living membranes

Permit free diffusion of water, Block the entrance of larger molecules

Faculative

Pertaining to the capacity of microbes to adapt or adjust to variations, not obligate. Example. The presence of oxygen is not obligate. Example: the Presence of oxygen is not obligatory for a facultative anaerobe to grow. See obligate

Exponential

Pertaining to the use of exponents, numbers that are typically written as a superscript to indicate how many ties a factor is to be multiplied. Exponents are used in scientific notation to render large, cumbersome numbers into small workable quantities.

The engulfment of large particles into vesicles withing a cell is called ________.

Phagocytosis

Uses sunlight as an energy source and carbon dioxide as a carbon source (example: cyanobacteria)

Photoautotroph

Uses sunlight as an energy source and an organic carbon source (example: purple photosynthetic bacteria)

Photoheterotroph

Which term is used to describe organisms that use the sun's light to directly power their metabolic pathways.?

Phototrophs

What environment factors have an influence on microbial growth?

Pressures, PH, Gases such as CO2 and O2, Tempeature

Which term refers to a class of organisms that grow slowly in cold temperatures but prefer room temperature environments?

Psychrotrophs

Which term describes the ability of some microbes to detect the relative number of bacteria within a specific area?

Quorum sensing

Why is prompt refrigeration of leftover food an effective way to prevent food spoilage?

Refrigeration temperatures are not optimal for reproduction and growth of food-associated pathogens

Antagonism

Relationship in which microorganisms complete for survival in a common environment by taking actions that inhibit or destroy another organism.

Metabolizes organic matter of dead organisms for energy and uses an organic carbon source (example: fungi)

Saprobe

Synergism

The coordinated or correlated action by two or more drugs or microbes tat results in a heightened response or greater activiity.

What determines a microbe nutritional type?

Source of carbon and source of energy.

Which instrument is used to determine relative cell density based on turbidity of a culture?

Spectrophotometer

Cells enter a survival mode, where they stop growing or greatly reduce their metabolic activity/growth due to depleted nutrients and the buildup of waste products ❀❀❀❀❀❀❀❀❀❀❀❀❀❀❀❀ Phase during which nutrient depletion and accumulation of wastes begin to slow cell growth such that the rate of cell increase equals the rate of cell death

Stationary Phase

Identify bacteria that require higher than normal levels of carbon dioxide for isolation.

Streptococcus pneumoniae and Neisserio

The conversion of a toxic superoxide ion to hydrogen peroxide requires which enzyme?

Superoxide dismutase

Which term describes any close nutritional relationship between two organism:

Symbiosis

____________ is a close nutritional association between individuals from two species that may be helpful, harmful or neither to both members.

Symbiosis

An interrelationship between two or more free-living organisms that benefits them but is not necessary for their survival is _____.

Synergism

An interrelationship between two or more living organisms that benefits them but is not necessary for survival.

Synergism

Which term is used to describe the coordinated action between two microorganisms or drugs that result in a heightened response or greater effectiveness?

Synergism

Osmosis

The diffusion fo water across a selectively permeable membrane in the direction of lower water concentration.

Diffusion

The dispersal of molecules, ions, or microscopic particles propelled down a concentration gradient by spontaneous random motion to achieve a uniform distribution.

A flow cytometer can provide which of the following types of data?

The # of cells in a sample Whether the cells in sample are alive.

Quorum Sensing

The ability of bacteria to regulate their gene expression in response to sensing bacterial density..

Lag Phase

The early phase of population growth during which no signs of growth occur.

Pinocytosis

The engulfment, or endocytosis, of liquids by extensions of he cell membrane.

Binary Fission

The formation of tow new cells of approximately equal size as the result of parent cell division.

Maximum temperature

The highest temperature at which an organism will grow.

Minimum temperature

The lowest temperature at which an organism will grow.

Exponential Growth (logarithmic or log) phase

The period of maximum growth rate in a growth curve. Cell population increases logarithmically.

If a cell LOSES water after being placed into a particular solution, what is true regarding the osmolarity of the solution?

The solution is hypertonic relative to the cell.

PH

The symbol for the negative logarithm of the H ion concentration ; p (power) or ( H+) A system for rating acidity and alkalinity.

optimum temperature

The temperature at which a species shows the ost rapid growth rate.

Generation/Doubling time

Time required for a complete fission cycle from parent cell to two new daughter cells.

Which of the following is an example of a biofilm commonly found in the human body? a)-Dental plaque b). Salivary secretions c). Ear wax d). Yellow or green discharge

a)-Dental plaque

What is a biofilm? a). -A group of bacteria that accumulate in layers and secrete an protective extracellular material b). -Free-floating bacteria that move through the blood to other sites c). -A layer of sugars that persist even after bacteria have been killed by antibiotics d). -A bacterial cell that secretes an extensive network of fibers around its cell wall

a). -A group of bacteria that accumulate in layers and secrete an protective extracellular material

Why are biofilms important in infectious disease? a). Bacteria in biofilms are often protected from antibiotics. b). The secreted extracellular "gunk" is highly damaging to tissues. c). Most microbes cannot cause disease without other microbes present.

a). Bacteria in biofilms are often protected from antibiotics.

A _________ derives its nutrients and energy from the organic matter of dead organisms, whereas a _________ lives in or on another living organism and derives its nutrients and energy from that living organism. a). saprobe; parasite b). parasite; saprobe c). autotroph; chemotroph d). phototroph; parasite e). phototroph; autotroph

a). saprobe; parasite

A relationship where microorganisms compete for survival in a common environment is know as _____.

antagonism

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

auto

A cell exposed to a hypertonic environment will _____ by osmosis. a). neither gain nor lose water b). lose water c). gain water d). burst

b). lose water

A(n) _____ is a microorganism that thrives under high hydrostatic pressure.

barophile

Most bacteria increase their numbers by _____. Multiple Choice hyphae formation sexual reproduction endocytosis binary fission

binary fission

Diffusion is a general term referring to the net movement of atoms and molecules along a concentration gradient, from an area of ________ concentration to an area of _______ concentration. a). low; high b). diluted; thick c). high; low

c). high; low

A microbe's nutritional type (such as autotroph or phototroph) is determined by its source of _____ and ____.

carbon and energy.

What cell structure regulates the passage of substrates into and out of the cell?

cell membrane

An organism who's energy sources comes from metabolizing the nutrients from other organisms

chemoheterotroph

What name is given to the device which provides a continuous culture system and removes wastes?

chemostat

Growth of a bacterial culture in a growth medium in a test tube is defined as a (n) ________culture, meaning the nutrients are limited and the waste products are not removed.

closed

Regarding oxygen, identify how microbes may be able to deal with its toxic properties.

contain deoxyifying enzymes live in environments lacking oxygen have relationships with organisms that protect it from oxygen's toxic effects.

Diffusion of water through a selectively permeable membrane is _________. a). pinocytosis b:. active transport c). facilitated diffusion d). osmosis

d). osmosis

An organism that can synthesize all its required organic components from CO2 using energy from the sun is a _______. a). chemoautotroph b). photoheterotroph c). chemoheterotroph d). photoautotroph

d). photoautotroph

Which phase of bacterial growth involves more cells dying than reproducing?

death

The time required for one complete cycle of binary fission is known as the ________ time or generation time. Multiple Choice binary log exponential doubling

doubling

List and define four different terms that describe an organism's sources of carbon and energy.

duplicate

A _________ can count the number of cells, measure the size of the cells, tell if the cells are dead or alive.

flow cytometer

In binary fission, the doubling time of a particular microbial species is aka its __________ time.

generation time

A ______curve is a graphical representation of the change in population size over time.

growth

S. aureus is classified as a facultative _____ because it can easily handle the higher salt concentrations found on human skin.

halophile

A solution which is _____ will cause a cell to lose water.

hypotonic

A solution which is _____ will cause a cell to swell with water.

hypotonic

An _____ nutrient is usually found in mineral deposits of the earth, water bodies, or the atmosphere.

inorganic

What is a microaerophile?

is a microorganism that requires oxygen to survive, but requires environments containing lower levels of oxygen than are present in the atmosphere

The term _____ describes two solutions having the same osmotic pressure such that, when separated by a semipermeable membrane, there is no net movement of solvent in either direction.

isotonic

Cells in the _____phase in the growth curve are metabolically active even though the number of cells is not increasing.

lag

The prefix "___" is added to "autotroph" to denote organisms which can use inorganic compounds in the environment to fix carbon dioxide with hydrogen atoms to make sugar.

litho

In active transport, molecules are moving across the membrane from an area of ______ concentration to an area of _____ concentration.

low, high

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

maximum

To obligate anaerobes, oxygen is

not used and toxic

An _____________is a microorganism that thrives in a hypertonic medium?

osmophile

A noun often used to describe organisms which cause disease is a ________.

pathogen

Which are essential functions for a living membrane?

permit free diffusion of water block the entrance of larger molecules

A(n) _____-troph is an organism which uses the sun's light to directly power it's metabolic pathways.

photo

Carbon, nitrogen, oxygen, and hydrogen are considered ________ nutrients because they are required in relatively large quantities and cannot be manufactured by microbes themselves. Multiple Choice phototrophic exogenous trace

phototrophic

A heterotroph that decoposes organic remains from dead organisms is also called a ____________.

saprobe

What determines a microbe's nutritional type?

source of carbon and source of energy

The _____ phase of bacterial cell growth is when there is equal number of cells dividing as there are dying.

stationary

Stationary Growth Phase

survival mode in which cells either stop growing or grow very slowly

A cell placed in a hypotonic environment will

swell with the influx of watear.

A cell placed in a hypotonic environment will ___________.

swell with the influx of water.

Microbes that can survive short exposure to high temperatures but are normally mesophiles are termed _____.

thermoduric

Microorganisms that prefer hot environments are termed ___________(45 degrees to 80 degrees C).

thermophiles

Bacterial oxygen tolerance patterns are determined by incubating a pure culture of a microorganism in _____ medium.

thioglycollate

Bacterial oxygen tolerance patterns are determined by incubating a pure culture of a microorganism in a blank medium ___________.

thioglycollate

Micronutrients (zinc, manganese) that are required by cells in sm amounts are termed _________elements.

trace

Match the data for a bacterial growth curve with the axis on which it is plotted.

x = time y = # of cells