Microbio CH. 3 Culturing

Identify any of the following which is characteristic on non synthetic media. - 5 grams of NaCl - 500 mg of Dextrose - 5 ml of Sheep Red Blood Cells - Blended heart tissues

- 5 ml of Sheep Red Blood Cells - Blended heart tissues

Identify all the correct answers associated with liquid media - Liquid media allows for the production of individual colonies - A slightly viscous liquid medium can be used to better understand the oxygen demands of microorganism - Liquid media are also called "broths" - Liquid media typically affords greater microorganisms growth

- A slightly viscous liquid medium can be used to better understand the oxygen demands of microorganism - Liquid media are also called "broths" - Liquid media typically affords greater microorganisms growth

Identify all the benefits of using agars compared to liquid cultures - Solid agar allows isolation of individual colonies - Solid agar allows greater growth of microorganisms - Solid agar allow differential identification of many microorganisms on the same agar plate

- Solid agar allows isolation of individual colonies - Solid agar allow differential identification of many microorganisms on the same agar plate

Dyes can be used as differential agents in media because they: - are pH indicators - are weak slats - have inhibitory properties - serve as growth factors

- are pH indicators

Identify all of the following which are considered " growth factor" typically added to enrich media - blood - vitamins - amino acid - agar

- blood - vitamins - amino acid

Media ingredients tat cannot be chemically defined include which of the following - sodium chloride - cell secretions - extracts of animals, plants or yeasts - disodium hydrogene phosphate - blood & serum

- cell secretions - extracts of animals, plants or yeasts - blood & serum

Which of the following describe selective media? - encourage the growth of desired organisms - select for growth of a brad spectrum of organisms - display visible differences among microorganisms - suppresses unwanted organisms

- encourage the growth of desired organisms - suppresses unwanted organisms

Agar as a media solidifying agnate has many benefits including: - retaining moisture and nutrients - not digestible as a nutrient by most microbes - being flexible and moldable - providing a nutrient source to the media - not harmful to microbes or to humans

- retaining moisture and nutrients - not digestible as a nutrient by most microbes - being flexible and moldable - not harmful to microbes or to humans

General purpose of media - are usually chemically defined synthetic media - usually contain a mixture of nutrients - include nutrient agar and broth - include Mannitol salt and MacConkey agar - are usually non-synthetic - grow a broad spectrum of microbes

- usually contain a mixture of nutrients - include nutrient agar and broth - are usually non-synthetic - grow a broad spectrum of microbes

____________ is a polysaccharide found in seaweed that is commonly used to prepare solid culture media

Agar

______________ acts as a solidifying agent for solid media and is beneficial in that provides a framework for nutrients and moisture but is not itself digestible.

Agar

Which of the following is absolutely true for all viruses and obligate intracellular microorganisms? A. must be airborne B. Must grow in or on living cells C. Require a very specific host or cell type D. must be resistant to light

B. Must grow in or on living cells

____________ salts is common component found in feces and therefore used in media to selectively culture Gram-negative bacteria

Bile

____________ media displays differences in colony size and color among various species of microorganisms.

Differential

_______________ media are designed to remove or reduce the penetration of oxygen into the media

Reducing

___________ media is inoculated by stabbing carefully in the center and is then later observed for the pattern of growth around the stab line; excellent for indicating motility of bacteria

Semisolid

______________ media are used to determine the motility of bacteria and to localize a reaction at the psefici site.

Semisolid

______________ media exhibit a clot like consistency at room temperature due to low agar concentrations

Semisolid

________________ media has a firmness midway between that of a broth (a liquid medium) and an ordinary solid medium.

Semisolid

__________ media are used to maintain and preserve specimens that have to be held for a period of time before clinical analysis.

Transport

Which of the following is the chemical source of agar found in typical agar media? a. Gelidium algae b. Staphylococcus aureus c. soil d. sugar cane

a. Gelidium algae

Any media which contains between 1% to 5% agar in it generally will have the word "agar" in its name; for example, nutrient agar a. True b. False

a. True

A medium that works by showing two reactions types, such as the use or non-use of a particular nutrient or color change in some colonies but not in others is called a: a. differential medium b. minimal medium c. enriched medium d. selective medium

a. differential medium

A media which contains complex organic substances and/or special growth factors which allows even fastidious organisms to thrive is called ____________. a. enriched medium b. general medium c. selective medium

a. enriched medium

_________________ solid media do not melt and contain material such as rice grains, cooked meat media, and potato slices a. nonliquefiable b. semi c. liquefiable d. enriched e. differential

a. nonliquefiable

Which is considered the most practical use of solid agars compared to liquid cultures? a. obtaining pure culture b. selective c. differential reporting d. oxygen requirements

a. obtaining pure culture

Which of the following media are chemically defined? a. synthetic b. nonsynthetic

a. synthetic

Liquid media can be used to better understand the oxygen demands of a microorganisms a. true b. false

a. true

Agar melts at _________ and does not resolidify until it cools to _________. a. 75C; 42C b. 100C; 42C c. 100 C; 50C d. 75C; 50C

b. 100C; 42C

A ______________ is an organic compound such as a vitamin or amino acid that must be provided in the diet to facilitate survival of certain bacteria a. mineral b. growth factor c. dye

b. growth factor

Fastidious organisms: a. require the absence of growth factors when grown in cultures b. require growth factor and/or complex nutrients c. grow on minimal media d. require simple nutrients when grown in culture

b. require growth factor and/or complex nutrients

What type of agar is motility agar? a. solid agar b. semisolid agar c. liquid broth

b. semisolid agar

The selective agent MacConkey Agar is _____________ salts.

bile

A(n) ____________ is an example of liquid medium and therefore, can be define as being liquid, water based, and not able to solidify at temperature above freezing.

broth

What is the optimum temperature at which agar can be poured without harming microbes or the handler? a. 42C and below b. 55C to 60C c. 45C to 50C

c. 45C to 50C

Which of the following is the chemical source of agar found in typical agar media? a. Soil (also known as dirt) b. Staphylococcus aureus c. Gelidium algae d. Sugar cane

c. Gelidium algae

Which of the following ingredients makes Mannitol salt agar (MSA) selective for staphylocccus species? a. crystal violet b. mannitol c. salt d. agar

c. salt

Media with a firmness midway between that of a broth (liquid medium) and a ordinary solid medium are called: a. semiliquid media b. seminutrient media c. semisold media

c. semisold media

In Brain Heart Infusion broth (a complex, non-synthetic media), none of the ingredients can be chemically defined, except: a. brain extract b. peptone extract c. sodium chloride d. beef extract

c. sodium chloride

Culture media whose compositions are precisely chemically defined are called: a. complex media b. nonsynthetic media c. enriched media d. synthetic media

d. synthetic media

The name given to media which allow different types of microbe to grow but are designed to display visible morphological or chemical difference among those microbes is ________________ media.

differential