Week 3: Physiology of Bacteria

bacterial colony

A _____________ is thousands of bacterial cells that grow from one original bacterial cell.

facultative saprophyte

A ________________ is an organism that usually obtains nourishment from living matter, but may obtain it from dead organic matter. It CAN BE a saprophyte (getting nourishment from dead matter), but it PREFERS being a parasite (getting nourishment from living matter).

strict/obligate saprophyte

A __________________ is an organism that can ONLY survive on dead or decaying organic matter.

facultative parasite

A __________________ is an organism that usually obtains its nourishment from dead organic matter, but may get it from living matter. It CAN be a parasite, but PREFERS being a saprophyte.

obligate saprophyte.

A bacterium that can only survive on dead or decaying organic matter is called a:

facultative saprophyte.

A bacterium that prefers living matter, but can also obtain nourishment from dead organic material is called a:

True

All organisms have an oxygen requirement, ranging from those organisms that cannot live without oxygen to those that could not survive with it. (T/F)

True

All pathogenic and non-pathogenic bacteria are heterotrophs (T/F)

True

All pathogenic, and many non-pathogenic bacteria, are heterotrophs. (T/F)

isotonic

An ____________ solution is one in which the total concentration of water molecules and solute molecules are the same on both sides of the semi-permeable membrane. If a bacterial cell happens to find itself in this type of solution, nothing will happen, not shrinking or swelling.

antagonistic

An _____________ relationship is one in which one organism inhibits the growth of another microorganism.

strict parasite.

An organism that can only survive on living matter is called a:

autotrophs

An organism that can utilize inorganic matter as food is called:

strict/obligate parasite

An organism that is completely dependent on its living host for survival is a _____________________ and can ONLY obtain nourishment this way.

True

Another name for the reproductive process of bacteria is simple transverse division. (T/F)

not less than 6 or more than 8

Bacteria grow best in a very narrow pH range, or one that is _________________________.

binary fission; transverse division

Bacteria reproduce by ____________, which is also known as _______________.

mesophiles

Bacteria that prefer moderate temperature and develop best at temperature between 25°C (77°F) and 40°C (104°F), are called ________________.

rupture

Bacterial cells placed in a hypotonic solution will:

True

Cold retards, or stops, growth and prolonged freezing destroys bacteria. (T/F)

light

Depending on the organism, _________ will also affects its growth.

1. Sufficient nutrients 2. Oxygen requirements 3. Moisture 4. Temperature 5. pH 6. Effects of Light 7. Osmotic pressure

For bacteria to grow and multiply, certain conditions must be met, including:

True

Growth is most rapid at certain degrees of alkalinity or acidity - a certain pH. (T/F)

o Strict (obligate) saprophytes o Strict (obligate) parasites o Facultative saprophyte o Facultative parasite

Heterotrophs fall into four different categories:

True

High temperatures are much more injurious to bacteria than low ones. (T/F)

pathogenic bacteria

However, _________________ grow best in a neutral (7) pH, or slightly alkaline environment (8 or 9).

psychrophiles or cyrophiles

If an organism is cold loving, meaning they thrive at temperatures between 0°C (32°F) and 25°C (77°F), they are called ______________ or _______________.

hypotonic solution

In a ________________, the solution has a lower concentration of solutes and a higher concentration of solvent (water) than within the cell. Therefore, water molecules enter the bacterial cell faster than they can leave, causing the bacterial cell to swell and burst.

hypertonic solution

In a ____________________, the solution has a high concentration of solutes and a lower concentration of water (solvent) than the cell. The water molecules move out of the bacterial cell faster than they can enter, which causes the cell to shrink.

microaerophiles.

Microbes that grow best in an amount of oxygen less than that contained in air are called:

True

Most bacteria can resist small changes in osmotic pressure, but are killed or inhibited by high concentration of either salt (as used in brine) or sugar. This process is used in the preservation of foods, such syrups and jellies with sugar and meats in brine. (T/F)

facultative anaerobes.

Organisms that are adaptable to either the presence or absence of free atmospheric oxygen, but prefer an environment with oxygen are called:

anaerobes.

Organisms that cannot grow in the presence of free atmospheric oxygen are called:

aerobes

Organisms that grow best in the presence of free atmospheric oxygen are called:

True

Organisms that obtain their food by breaking down organic matter into simpler chemical substances are called heterotrophs. (T/F)

104°F

Proteins coagulate at ________.

water

Seventy-five to ninety percent of the bacterial cell is _____.

plasmolysis

Shrinkage of the cell is called:

crenation

Shrinkage of the red blood cell is called ___________.

True

Temperature is an important factor for bacterial growth. For each organism, there is a minimum, optimum, and maximum temperature. (T/F)

minimum temperature

The ________________________ is the lowest temperature at which an organism will grow; it is the temperature below which bacterial growth will not take place.

maximum temperature

The _________________________ is the highest temperature at which growth is possible; the temperature above which bacterial growth will not take place.

osmotic pressure

The greater _______________ inside the cell keeps the protoplasm of the cell firmly against the cell wall and the cell is said to turgid (swollen or bloated).

7

The interior of a cell is at a pH of ___, a neutral point.

minimum temperature.

The lowest temperature at which growth for a species will take place is called:

7 - 9

The necessary range for pathogenic bacteria is __________.

plasmoptysis

The process of rupturing a bacterial cell is called:

hemolysis

The process of rupturing or bursting a red blood cell is called ___________________.

False

The second word of a scientific name is the species and it is capitalized. (T/F)

optimum temperature.

The temperature at which a species grows best is called:

optimum temperature

The temperature at which an organism grows best is called the ____________________.

strict or obligate

The term ________ or _________ means they can only get their nourishment from one source. There can be no deviation - at all.

o Strict (obligate) aerobes o Strict (obligate) anaerobes o Microaerophilic o Facultative aerobes o Facultative anaerobes

There are 5 categories of oxygen requirement:

o Mutualism o Commensalism o Parasitism

There are different types of symbiosis:

binary fission; transverse division

This method of reproduction is an asexual reproduction in which the cell splits into two parts, each of which develops into a complete individual. The entire process only takes about 15 to 30 minutes from newborn to adult.

mesophilic bacteria.

Those bacteria that grow best at a relatively moderate temperature are called:

thermophilic bacteria.

Those bacteria that grow best at relatively high temperatures are called:

psychrophilic bacteria.

Those bacteria that grow best at relatively low temperatures are called:

facultative anaerobes.

Those bacteria that prefer to live in the presence of free oxygen but can live in its absence are

higher

Under normal conditions, there is a ___________ concentration of dissolved substances within the cell than outside of it.

highly destructive

Violet, ultraviolet and blue lights are _____________________ to bacteria.

True

Water dissolves the food material in the environment of the bacterial cell, so that the food can be absorbed. Drying is highly detrimental to bacterial growth. Delicate bacteria will resist drying for a short time, but those with spores may resist drying (desiccation) for years! (T/F)

synergistic effect

When a symbiotic relationship produces a unique effect, it is referred to as a _____________________.

synergism

When two organisms living together produce a reaction that neither could produce alone we call the relationship:

Aerobes

____________ are organisms that grow best in the presence of free atmospheric oxygen (man).

Osmosis

____________ is the movement of water (solvent) through a semi-permeable membrane from an area of lower solute concentration to an area of higher solute concentration.

Heterotrophs

_____________ are organisms that must obtain their nourishment from breaking down complex organic matter into simpler chemical substances.

Synergism

_____________ occurs when the harmonious action of two microorganisms produces an effect that neither could produce alone.

Direct sunlight

______________, because of its content of ultraviolet light kills many bacteria within a few hours.

Anaerobes

_______________ are those organisms that cannot grow in free oxygen, but must obtain their oxygen from oxygen containing compounds.

Bacterial colonies

_______________ begin with one bacterial cell that, through binary fission, becomes multiple cells.

Parasites

_______________ gain their nourishment from living matter.

Symbiosis

_______________ is a situation in which two dissimilar organisms live together.

Osmotic pressure

_______________ is pressure that develops when two solutions of different concentrations are separated by a semi-permeable membrane, such as the cell membrane found in bacteria.

Facultative aerobes

________________ are microorganisms that prefer an environment devoid of oxygen, but have adapted so that they can live and grow in the presence of oxygen; they CAN BE an aerobe, but PREFER being an anaerobe. These organisms usually obtain oxygen from oxygen-containing compounds, but may obtain it also from free oxygen.

Saprophytes

________________ obtain their nourishment from non-living (dead or decaying) organic matter.

Thermophiles

_________________ are bacteria that love the heat and survive best at temperature between 40°C (104°F) and 70°C (158°F).

Facultative anaerobes

_________________ are microorganisms that prefer an oxygen environment, but are capable of living and growing in the absence of oxygen; they CAN BE an anaerobe, but PREFER being an aerobe. These organisms usually obtain oxygen from the atmosphere, but may obtain it also from oxygen-containing compound.

Strict (obligate) aerobes

_________________ are organisms that cannot develop at all in the absence of free oxygen; a microbe that can only live in the presence of free oxygen, in direct opposition to strict (obligate) anaerobes

Microaerophilic

___________________ is a microbe that grows best in an amount of oxygen that is less than that contained in air; it requires very little free oxygen.

Strict (obligate) anaerobes

____________________ are organisms that are vulnerable to free oxygen; they can only exist in the absence of free oxygen.

Autotrophic bacteria

__________________________ are organisms that are self-nourishing; that is they make their own food by building organic compounds in their protoplasm from simpler inorganic substance.

Heterotrophic bacteria

____________________________ are responsible for numerous diseases in humans.

Mutualism

both organisms benefit

Commensalism

one organism benefits and the other is not affected

Parasitism

one organisms benefits at the other's expense

facultative

the term ________________ means able to do a number of things or can do more than it appears. ______________ organisms "can be" one way, but "prefer to be" another.