Laboratory Culture of Microorganisms Flashcards
After the ethanol rinse (alcohol) in the Gram Staining procedure, the Gram-positive cells would appear ______ and the Gram-negative cells would appear ________.
purple; colorless
bacteria need proper _______ to grow in lab
nutrition
all bacteria have different nutritional requirements but all require:
Carbon
Hydrogen
Oxygen
Nitrogen
Phosphorus
Sulfur
– CHONPS!
some bacteria need certain ____ ____ (organics in medium)
trace metals
macromolecular composition of a cell: protein = ____%
55%
macromolecular composition of a cell: lipid = ____%
9.1%
macromolecular composition of a cell: polysaccharide = ____%
5%
macromolecular composition of a cell: lipopolysaccharide = ____%
3.4%
macromolecular composition of a cell: DNA = ____%
3.1%
macromolecular composition of a cell: RNA = ____%
20.5%
elemental composition of E. coli: CARBON = ____%
50% (the rest go down in numbers from CHONPS)
nutrient preparations devised to support the growth (reproduction) of microorganisms
culture media
large quantities of these are need by microorganisms (ex: carbon)
macronutrients
smaller quantities of these are needed by microorganisms
micronutrients
2 types of micronutrients:
- trace metals
- growth factors (organics or vitamins)
culture media can be ____ or _______
solid or liquid
solid media are usually solidified with _______
agar
chemical composition types of media (2):
- defined (synthetic)
- complex
physical natures of media (3):
- liquid
- semisolid
- solid
FUNCTIONAL types of media (5):
- supportive (general purpose)
- enriched
- minimal
- selective
- differential
type of chemical composition of media: EXACT composition (qualitative AND quantitative) is known; very specific; don’t have to add trace elements all the time to it (usually already in water); chemical formula AND amounts for all ingredients
defined media
what must be included for a media to be defined (2)?
chemical formula AND amounts for all ingredients
type of chemical composition of media: contain some ingredients of unknown chemical composition and/or concentration; no chemical formula
complex media
if you have a SINGLE ingredient without a formula, what kind of chemical compostion is the media?
complex
what kind of chemical composition is: Yeast extract 5g and Peptone 5 g
complex
common complex media components (5):
- peptones
- extracts
- agar
- blood
- soil
common complex media component: protein hydrolysates prepared by the partial digestion of various protein sources such as casein and soybeans
peptones
common complex media component: aqueous extracts, usually of BEEF or YEAST
extracts
common complex media component: sulfated polysaccharide used to solidify liquid media; most microorganisms CANNOT degrade it; comes from red seaweed
agar
anytime you see ______, _______, _____, or ______, you KNOW the media is complex
peptones, yeast, beef, or agar
functional type of media: support the growth of many microorganisms; usually complex
general purpose media (supportive)
example of a general purpose (supportive) media =
tryptic soy agar (TSA)
functional type of media: general purpose media supplemented with highly nutritious substances such as blood
enriched media