Microbiology: Chapter 6 Growth and Culturing of Bacteria Flashcards

the increase in the number of cells, which occurs by cell division

Bacteria generally divide by which two ways

Which cell (prokaryotic or eukaryotic) follow a cell cycle?

How many circular chromosomes do most bacteria have?

What are the phases of growth found in standard bacterial growth curves

phase of bacterial growth where cells are actively producing ATP preparing for cell division

phase of bacterial growth that is the period of greatest cell division

the time required for a population of cells to double

new cells are produced very near the rate at which cells die; cells begin to die due to a build-up of waste products and possible shortages of nutrients, oxygen, and water

fewer cells are able to divide and more and more cells die as conditions degrade

when cells exhibit unusual shapes [many cells may undergo this in decline (death) phase]

in decline (death) phase some genera of bacteria produce these for survival

generally formed when a single cell divides to produce a large number of cells

all of the cells in a colony descend from a single what?

How does a colony grow?

Cells at the edges have a better advantage because of what?

give three characteristics of E. Coli

what is so bad about the killer strain of E. Coli 0157 H7

What is the generation time for the killer strain of E. Coli 0157 H7

prefers to grow where no oxygen is present but is able to adjust to and tolerate the environmental condition, but it can also live in other conditions

list five ways to measure bacterial growth

this type of bacteria grows at the bottom of a solid medium

all cells remain on the surface of the solid medium (aerobe)

this method is used if you are not sure if it is aerobe or anaerobe

30 to 300 per plate

begins with an estimate, then dilutions and plates

cloudiness

allows the cells in a sample to be dried and then weighed

the measurement of metabolic products in a sample can also be used indirectly to do what?

what are the two major factors affecting bacterial growth

What are the physical factors affecting bacterial growth?

examples of bacteria that grow best at their optimum pH.

Examples of bacteria that grow better at extreme or different body temperatures

examples of major groups of aerobes and anaerobes that affect bacterial growth

most vegetative cells can live only a few hours without this physical factor that affects bacterial growth

physical factor that affects bacterial growth that is exerted by standing water

salt-loving organisms

As far as nutritional facts are concerned what factors affect bacterial growth

some bacteria have special nutritional requirements and makes them hard to grow in a laboratory. These bacteria are known as what?

elements that are required in very small amounts are ions and are needed as cofactors

The type of enzymes and the number of enzymes present determine the what of an organism which normally has fewer types and numbers or enzymes than less nutritionally complex organisms

bacterial interactions affecting growth explain some peculiar adaptive aspects of bacterial bioluminescence

acts as a kind of "superorganism" with different cells responding differently within it

the formation of endospores

two genera known for producing endospores

normally produced due to deteriorating environmental conditions

The core (which consists of what) of an endospore contains what is needed to return to a vegetative cell when conditions improve

What are the two methods of obtaining pure cultures

method of obtaining pure cultures that uses agar plates

method of obtaining pure cultures that makes use of serial dilution

When we classify agar it can be what or what?

What are examples of natural culture media?

type of culture media that is classified by chemical make up

type of synthetic culture media that the ingredients and exact amounts are known

type of synthetic culture media that the ingredients are known, but the exact amounts may vary from batch to batch

type of culture media that is classified by how the agars are used

type of culture media that encourages one species and discourages others

type of culture media that you can see a pH or color change in

type of culture media that has extra vitamins and minerals added to it

minimize the chances that culture will be contaminated by organisms from the environment or that organisms, especially pathogens, will escape into the environment

what are the three ways to maintain cultures

a way to maintian cultures (not used for lab cultures) a pure culture that can be maintained indefinetly once an organism has been isolated

a way to maintain cultures that is a culture in which organisms are maintained in a dormant state

a preserved culture that maintains the organisms with the characteristics as originally defined

What is involution?

Name at least two ways to measure bacterial growth

What is meant by "generation time"?

What is selective medium?

How do we obtain pure cultures? (the book listed two ways)

cell division in bacteria is primarily by the process of what?

Cell division in yeast occurs primarily by what?

The bacterial growth curve is divided into how many phases?

Lag phase is characterized by what

In stationary phase what happens to cell populations numbers?

Endospores are most likely to be produced in great numbers in what?

The solidifying agent most commonly used in microbiological media is what?

the appropriate number of colonies to count when performing plate counts is

Most of the bacteria that cause disease in humans are _______.

Bacteria that prefers to grow between 25C and 40C are termed

An organism that prefers high concentrations of carbon dioxide is termed a _____.

An aerotolerant anaerobe:

The enzyme responsible for the breakdown of peroxide to water and oxygen is called ______.

A halophile requires high what for growth?

Bacteria that are difficult to cultivate due to special nutritional needs are termed what?

The process of an endospore becoming a vegetative bacterium is called what?

The spore coat is composed primarily of what?

MacConkey agar is what?

A culture that has been freeze-dried is termed

Culture media that allows some microbes to grow but suppresses others is what?