Bacterial Cultivation/Culturing Flashcards
3
What is A microbial culture?
is a way of multiplying microorganisms under
controlled laboratory circumstances by allowing them to replicate in preset culture
media.
Where is A microbial culture used for?
used to identify the type of organism, as well as its
abundance in the sample under investigation.
To investigating their morphology and identity, what you do?
Bacterial isolation. bacterial properties, or cultivating bacteria, is the first stage .
keeping stock cultures alive or dead.
Alive
Why calculate the number of viable organisms ?
to see if you’re allergic to antibiotics.
to
develop antigens for use in the laboratory.
bacteria must also be cultivated in vitro:
for certain genetic research and cell modifications
Classification Culture Media based on consistency?
A.Liquid media.
B. Solid media.
C. Semi solid media
Bacterial culture media can be classified in at least in three ways:
- Consistency
- Nutritional component
- Functional use
Where keep A.Liquid media?
test-tubes, bottles or flasks.
what referred sometimes about Liquid media?
“broths” (e.g nutrient broth)
In liquid medium,
bacteria grow ….. producing general …….
- uniformly
2. turbidity
Where are a liquid medium use ?
Mostly
used for inoculums preparation.
Do you added agar in liquid medium?
No agar is added.
What is An agar plate ? and what contain ? and what to use for?
is a Petri dish that contains a growth medium
(typically agar plus nutrients)
used to culture microorganisms.
Do you added agar in the sold medium or agar plate ?
2% of agar is added.
…. is the most commonly used solidifying agent.
Agar
Classification Culture Media based on Nutritional Components:
A. Simple media.
B. Complex media.
C. Synthetic or chemically defined media
What mean the colony?
single bacterium, supplied with right
nutrients, will multiply on the solid medium in a limited area to form a colony,
which is a mass of cells all descended from the original one.
How obtained Pure cultures? what are use?
using variety of special techniques.
All
glassware, media and instruments must be sterilized i.e. aseptic techniques
Give examples about agar that use in sold medium?
Examples include Nutrient agar and
Blood agar.
What can you observe when use a sold medium?
Colony morphology, pigmentation, hemolysis can be appreciated
Where do use the semi-solid medium?
can be used in fermentation studies, in determine bacterial motility, and in promoting an aerobic growth.
Semi-solid media:
Such media are fairly soft
Give examples of
Semi-solid media ?
(Hugh & Leifson’s oxidation fermentation)
Do you added agar in the semi-solid medium?
0.5% agar is added.
What the benefits of the semi-solid medium?
useful in demonstrating bacterial motility and separating motile from non-motile strains.
What the natural of bacteria existing in An artificial culture media?
- Water,
- a supply of carbon
- energy
- a source of nitrogen,
- trace elements,
- some growth agents make up a
culture media. - The medium’s pH must be adjusted correspondingly.
An artificial culture medium must provide :
the environmental and nutritional
conditions
cultivation on solid media is
another convenient way of …… in mixture.
separating bacteria
basic requirement for obtaining a pure culture are ….
medium
solid
In the laboratory bacteria are isolated and grown in pure culture in order to:
study the functions of a particular specie
What is the most important feature of pure culture?
++pure culture is a population of cells or
growing in the absence of other species or types.
++a pure culture may originate from
a single cell or single organism
What is Synthetic media/Chemically defined media? How prepared? Give examples?
∆Specially prepared media for
research purposes where the composition of every component is well known.
∆ It is
prepared from pure chemical substances.
∆ex: peptone water (1% peptone + 0.5%
NaCl in water)
Give me examples about the simple media?and do you added agar?
ex: NB, NA. Nutrient
Broth consists of peptone, yeast extract and NaCl. When 2% of agar is added to Nutrient Broth it forms Nutrient
