Question

Shape of staphylococcus bacteria
A. Circular
B. Oval
C. Elongated
D. Cubical

Answer 1

Hint: As the name of the bacteria is staphylococcus, in which the word coccus denotes the spherical appearance of the bacteria. In shape, bacteria are differentiated on the basis of various types.

Complete Answer:
- When this bacteria is viewed under the microscope, some species of staphylococcus have been shown to produce relatively small colonies that have a relatively smooth and glossy appearance on the outer surface. Basically, staphylococcus bacteria are non-motile and therefore lack structures which are required for motion of the bacteria for eg. Cilia or flagella.
- Staphylococcus bacteria are spherical shaped bacteria (cocci). Specially these bacteria are not like other cocci bacteria that may exist as single cells or in pairs, Staphylococcus forms clusters and resembles grape-like clusters.
- The Grape-like cluster of Staphylococcus is the result of a single coccus dividing in more than one plane.
- In the clusters of the bacteria, individual cells may have size differences. However, this difference in size has also been detected among different species with the size ranging from 0.5 to 1mm in diameter.
- Staphylococcus are the bacteria which are circular in shape. These bacteria are identified as the cause of various pyogenic infections in humans, these bacteria are Gram-positive and these are characterized by irregular clusters. They are widely distributed in nature and staphylococcus bacteria can be found on the skin and mucous membranes (nasopharynx and gastrointestinal tract) of various animals and birds.
- In more details to the bacteria, The genus is divided into coagulase-positive staphylococci which are pathogenic and the coagulase-negative staphylococci (e.g. Staphylococcus epidermidis) which are considered as common commensals on the skin. They can also behave as opportunistic pathogens under certain conditions and cause infections. As extracellular bacteria, Staphylococci bacteria are very hardy and thus capable of surviving for a long period of time on various surfaces.

These bacteria are characterised in different groups :
- Monococcus (occurring singly)
- Diplococcus (in twos)
- Tetracoccus (in tetrads)
- Streptococcus (in chains)
- Staphylococcus (irregular grape-like clusters)
- Sarcina (3-dimensional geometrical forms)

Therefore, the correct answer is a- circular.

Note: It has to be noted that the Members of the genus Staphylococcus are distributed worldwide and can be found wherever human beings and other warm-blooded animals exist. Early on, researchers noticed that Staphylococcus bacteria are often found in association with other organisms (particularly warm-blooded organisms).