Bacterial Shapes and Groupings – Answer Sheet
The four basic morphological shapes are:
1. Coccus
(pl. Cocci
) [English: spheres
]
2. Bacillus
(pl.
Bacilli
) [English: rods
]
3. Spirillium
(pl.
Spirilla
) [English:
]
4. Helix
(pl.
Helixes
spirals
)
Bacteria can exist as solitary cells, in pairs ( diplo
-), in chains
(
staphylo
strepto
-), in random sized groups or clusters (
groups of specific sizes (i.e. groups of eight) (
sarcina
).
Label each of the following bacteria as to its shape and grouping:
1. Diplococcus pneumoniae (the cause of bacterial pneumonia)
spherical
pairs
2. Streptococcus lactis (used in the commercial production of cheese)
spherical
chains
3. Staphylococcus aureus (main cause of boils or furuncles)
spherical
clusters
4. Spirillum volutans
spirals
5. Bacillus anthracis (cause of Anthrax)
rods
Other Bacteria:
Nitrosococcus - soil bacteria that convert ammonia to nitrates;
Clostridium tetani - lockjaw;
Comunobacterium diptheriae - diphtheria;
Mycobacterium tuberculosis - tuberculosis;
Lactobacillus - bacterium that causes milk to sour.
Rochalimaea henselae - carried on cats and can cause infections in humans
Less common bacteria:
Cholera;
Relapsing fever;
Typhoid fever.
Lyme disease;
Scarlet fever;
Meningitis;
Syphilis;
-) or in