The Form of Bacteria

The form of bacteria is vary depend on the kind of bacteria, most of bacteria are on the form of coccus, rod or bacillus and spiral forms.

1. Coccus Bacteria
a. Coccus form of bacteria is a spherical or oval form, this bacteria have on of several distinct arrangement based on their planes of division.

• Diplococcus is arrange in pairs
• Streptococcus is arrange in chain

b. In two planes form produce tetrad arrangement, tetrad is arranged in squared form of 4 angles.
c. In three planes form produce a sarcina arrangement, this bacteria is arranged in cubes with 8 angles.
d. In random planes form produce a staphylococcus arrangement, staphylococcus or cocci arranged in irregular, often grape-like cluster. An average coccus is about 0.5 – 1.0 micrometer in diameter.

2. The rod or bacillus
Bacilli are rod-shaped bacteria. Bacilli all divide in one plane producing a bacillus, streptobacillus, or coccobacillus arrangement.
a. bacillus: single bacilli
b. streptobacillus, a streptobaccillus is arranged in chains
c. coccobacillus, this bacteria form is oval and similar to a coccus. An average bacillus is 0.5-1.0 µm wide by 1.0-4.0 µm long.

3. The spiral
The spirals bacteria come in one of three forms, a vibrio, a spirillum, or a spirochete.
a. vibrio, the form is in curved or comma-shaped rod
b. spirillum, the form is rigid spiral and thick
c. spirochete, this form is thin and flexible spiral The size of spirals range are about 1 µm to over 100 µm in length.

4. Exceptions to the above shapes
Trichome-forming, sheathed, stalked, filamentous, square, star-shaped, spindle-shaped, lobed, and pleomorphic.