If cells are grown in media containing amino acids labeled with radioactive nitrogen, most of radioactivity will be found in the cells
DNA and proteins
Pathogenic bacteria isolated from the respiratory or intestinal tracts of human are
capnophiles that grew best in carbon dioxide incubators.
The introductory biosafety level in labs is
BSL 1
The biosafety level working with potentially airborne pathogens is
BSL 3
Which of the following added to a culture medium will neutralize acids?
buffers
Salts and sugars work to preserve foods by creating a
hypertonic enviroment
The term aerotolerante anaerobe refers
It does not use oxygen but tolerates it
Which the following is advantage of the standard plate count?
determines the number of viable cells
Which of the following is an advantage of the direct microscopic count
requires no incubation time
Most bacteria reproduce by
binary fusion
Most bacteria grow best at PH
PH 7
Most fungi grow best at PH
PH 5
A culture medium on which only gram-positive grow and a yellow halo surrounds S. aureus colonies is called
Selective and differential medium
A culture medium consisting of agar, peptone and beef heart is a
complex medium
During which growth phase will gram positive bacteria be most susceptible to penicillin
log phase
The source of nutrients in nutrient agar is
peptone and beef extract
Patients with indwelling catheters are susceptible to infections because
biofilms develop on catheters
Pure cultures can easily be obtained on streak plates, even if the desired bacteria are present in very low concentrations
False
Turbidity is an indirect measurement of bacterial growth that can be measured using a pectrophotometer
True
Filtration methods are used to count bacteria present in very low concentrations, such as in lakes and streams
True
Nitrogen-fixing bacteria, such as cyanobacteria, can use atmospheric nitrogen for their nitrogen source
True