Systematic bacteriology

Question 1

How are microorganisms classified

Answer 1

Appearance
enzyme/ metabollic tests
growth requirements
molecular tests

Question 2

How can microorganisms be identified under a microscope

Answer 2

pure culture?
shape/size
grouping
structures
staining

Question 3

What are the common shapes of bacteria

Answer 3

cocci - spheres
bacilli - rods
spiral shaped

Question 4

what does a division in 1 plane for a coccus produce

Answer 4

diplococcus

Question 5

how can cocci produce chains

Answer 5

division in 1 plane to produce 4-20 cocci

Question 6

How do cocci produce clumps

Answer 6

division in 3 planes

Question 7

How do chains of bacilli form

Answer 7

delayed separation of the cell wall

Question 8

which form of bacteria are more commonly found in chains

Answer 8

gram positive

Question 9

what shape are fuse-form pathogens

Answer 9

long slender rods

Question 10

What are the types of spiral-shaped bacterium

Answer 10

rigid
flexible

Question 11

what makes a spiral shaped bacteria flexible

Answer 11

flagella attached at one end and corkscrews along the inside - better mobility

Question 12

What is a spore?

Answer 12

A structure from a bacteria that allows it to spread and survive in an unfavourable environment

Question 13

What does a spore consist of

Answer 13

Contains a chromosome in the centre surrounded by a membrane made up of proteins

Question 14

Are spores alive

Answer 14

no - therefore are difficult to degrade

Question 15

Which types of pathogens produce spores

Answer 15

anaerobic

Question 16

What is a gram stain

Answer 16

distinguishes between gram negative and gram positive bacteria due to their cell walls

Question 17

Why does gram staining not work on all bacteria

Answer 17

if they have a lipid rich/waxy cell wall - will not take up stain

Question 18

How are microorganisms classed

Answer 18

appearance
growth requirements
enzyme/metabolic tests
molecular tests

Question 19

Which types of organisms require oxygen in lab

Answer 19

obligate aerobes

Question 20

Which type of bacteria can grow in absence or presence of oxygen

Answer 20

facultative anaerobes

Question 21

How is a selective media used for growth of specific prokaryotes

Answer 21

By containing the presence of specific substances that permit growth of one organism

Question 22

What type of media can facilitate identification of prokaryotes

Answer 22

differential media

Question 23

What are the ways haemolysis occurs on blood agar plates

Answer 23

alpha - partial
beta - complete
gamma - no haemolysis

Question 24

What types of biochemical reactions can be used to identify prokaryotes

Answer 24

utilisation of carbon sources
utilisation of amino acids
coagulase (enzyme production)

Question 25

How are serological tests used

Answer 25

demonstrate specific antigens or antigen-binding interactions
Agglutination

Question 26

How is agglutination used to identify bacteria

Answer 26

Antibody + signal are mixed, Antigen will either bind or remain suspended in solution