BIOL-2116 Final Exam Study Set Questions
and Answers with Complete Solution | New
2026/27 Update
Classification of bacteria does what? - ANSWERS groups species according to
evolutionary relationships
Identification of bacteria does what? - ANSWERS relies on tests that may have
little to do with evolutionary relationships
Specificity - ANSWERS the ability of a test to identify a single pathogen, high
specificity reduces the number of false positive results
Sensitivity - ANSWERS the smallest quantity of a pathogen (or product of a
pathogen) that a test can identify, high sensitivity reduces number of false
negative results
Morphology - ANSWERS shape, size, presence of fijmbraie, flagella,
endospores etc., more useful in identifying eukaryotic organisms
Differential Staining - ANSWERS Allows for the identification of cells using more
then one chemical or stain to identify the structural differences of the cells in the
sample
,Examples of differential staining include what? - ANSWERS gram staining, acid-
fast staining, Schaeffer-Fulton endospore stain, flagella staining
What colour do gram-positive cells appear? Negative? - ANSWERS purple, pink
In addition to using gram staining what other test is used to identify
N.gonorrhoeae and why? - ANSWERS oxidase test, in order to differentiate
between the gonorrhoea and other bacteria
Biochemical results - ANSWERS Most rely on detecting the presence or
absence of a particular enzyme or biochemical pathway such as catalase
The Enterotube 2 is an example of what test? What does it do? - ANSWERS
rapid biochemical identification system, each compartment is scored and the pre
assigned code that is produced identifies the most likely bacteria present
Serology - ANSWERS Study of antigen-antibody reactions in vitro
Serological tests usually have high _______________, because epitopes are very
often specific to ________ ______ of bacteria - ANSWERS specificity, one type
ELISA (enzyme-linked immunosorbent assay) - ANSWERS - Known antibodies
bound to microplate well
- Unknown sample of bacteria added
- Binding of bacteria to antibody allows identification
, Western Blotting - ANSWERS Method for detecting microbial proteins in the
blood of an infected patient
What indicates a positive Western Blotting test result? - ANSWERS antibody
flagged with fluorescent dye binds to cells
Phage typing - ANSWERS Different strains of the same bacteria may show
different degrees of pathogenicity & different sensitivity to antibiotics, some may
show susceptibility to phage infection (Type A responds to phage 1 and B
responds to phage 2)
Fatty acid profiles - ANSWERS Fatty acids are components of cell membranes,
different species show unique ratios of different fatty acids
Fatty acids can be isolated from infectious bacteria and can identify what species
is present
Flow cytometry - ANSWERS - A 'flow cytometer' is a piece of equipment that
forces a liquid sample through a small tube
- Electrical conductivity can be measured in the tube to detect the presence of
bacterial contamination
- Fluorescence can also be measured
DNA base composition - ANSWERS the amount (A+T)/(C+G) is variable
between species, if we know the composition of the different strains we can
isolate the DNA of the bacteria in question and identify it this way
and Answers with Complete Solution | New
2026/27 Update
Classification of bacteria does what? - ANSWERS groups species according to
evolutionary relationships
Identification of bacteria does what? - ANSWERS relies on tests that may have
little to do with evolutionary relationships
Specificity - ANSWERS the ability of a test to identify a single pathogen, high
specificity reduces the number of false positive results
Sensitivity - ANSWERS the smallest quantity of a pathogen (or product of a
pathogen) that a test can identify, high sensitivity reduces number of false
negative results
Morphology - ANSWERS shape, size, presence of fijmbraie, flagella,
endospores etc., more useful in identifying eukaryotic organisms
Differential Staining - ANSWERS Allows for the identification of cells using more
then one chemical or stain to identify the structural differences of the cells in the
sample
,Examples of differential staining include what? - ANSWERS gram staining, acid-
fast staining, Schaeffer-Fulton endospore stain, flagella staining
What colour do gram-positive cells appear? Negative? - ANSWERS purple, pink
In addition to using gram staining what other test is used to identify
N.gonorrhoeae and why? - ANSWERS oxidase test, in order to differentiate
between the gonorrhoea and other bacteria
Biochemical results - ANSWERS Most rely on detecting the presence or
absence of a particular enzyme or biochemical pathway such as catalase
The Enterotube 2 is an example of what test? What does it do? - ANSWERS
rapid biochemical identification system, each compartment is scored and the pre
assigned code that is produced identifies the most likely bacteria present
Serology - ANSWERS Study of antigen-antibody reactions in vitro
Serological tests usually have high _______________, because epitopes are very
often specific to ________ ______ of bacteria - ANSWERS specificity, one type
ELISA (enzyme-linked immunosorbent assay) - ANSWERS - Known antibodies
bound to microplate well
- Unknown sample of bacteria added
- Binding of bacteria to antibody allows identification
, Western Blotting - ANSWERS Method for detecting microbial proteins in the
blood of an infected patient
What indicates a positive Western Blotting test result? - ANSWERS antibody
flagged with fluorescent dye binds to cells
Phage typing - ANSWERS Different strains of the same bacteria may show
different degrees of pathogenicity & different sensitivity to antibiotics, some may
show susceptibility to phage infection (Type A responds to phage 1 and B
responds to phage 2)
Fatty acid profiles - ANSWERS Fatty acids are components of cell membranes,
different species show unique ratios of different fatty acids
Fatty acids can be isolated from infectious bacteria and can identify what species
is present
Flow cytometry - ANSWERS - A 'flow cytometer' is a piece of equipment that
forces a liquid sample through a small tube
- Electrical conductivity can be measured in the tube to detect the presence of
bacterial contamination
- Fluorescence can also be measured
DNA base composition - ANSWERS the amount (A+T)/(C+G) is variable
between species, if we know the composition of the different strains we can
isolate the DNA of the bacteria in question and identify it this way
