Micro Bio Lab 4: Environmental factors affecting growth

Thermophile

Grows above 45 C

Mesophile

-Growth range: 10c -47c

-Optimal range: 25C-35C

Psychrophile

-Growth range: -5C to 20C

-Optimal range: -5C to 5C

Psychrotroph

Able to grow as low as 0C-5C but may grow well at higher temps with a max temp well above 20c

Aerobic

Process that requires oxygen

Anaerobic

poisoned by oxygen

Facultative aerobe

an organism that can live with or without oxygen

-prefers O2

Microaerophilic

A microorganism that requires very little free oxygen

Ambient air incubation

incubate in the air found in the enviroment

Microaerophilic incubation

CO2 is pumped into the jar by a candle or in large labs incubator into which CO2 is pumped.

Anaerobic incubation

No oxygen present.

strip is placed into container blue when oxygen present white when oxygen absent

What is all required in a graph?

1. Title

2. Both Axis labeled

3. Correct Parameter on each axis

4. Units of measure clearly stated

5. Points on the axis evenly dispersed

6. More than one line = ledger needed

how do you create an anaerobic jar?

1. airtight jar

2. H2 is added to convert O2 to H2O

3. A strip is added that is blue with oxygen and white with no oxygen present.

E. Coli oxygen requirement?

Facultative

Bacillus subtilis oxygen requirement

obligate aerobe (strict need O2)

Clostridium sp. oxygen requirement?

obligate anaerobes (poisoned by O2)

State the reason Serratia marcescens is able to produce a color at one temperature and not at another.

-At lower temperatures (around 20–30°C), the enzymes function properly → red pigment forms.

-At higher temperatures (around 37°C), these enzymes are inactive or less efficient → no pigment (colonies appear white or colorless).

Room temperature in C

20-25C

Fridge temp in C

2-8 C

Human body temperature

37°C

Boiling water

100 C