What sizes and shapes do bacteria have?

Bacteria do have fixed size and shape.


Size varies from 0.5 to 50 microns, generally 1 to 5 X 0.5 - 1 Micron. ( 1 micron = a millionth part of a milimeter )


Shape is variation of two basic shapes - spherical i.e. Cocci (singular Coccus ) and cylindrical i.e. rods or Bacillus. All other forms are variations of these two.


Cocci in pairs - Diplococcus


Cocci in cains - Streptococcus


Cocci in clusters - Staphylococcus


Cocci in tetrads - Gaffkia


Cocci in cubes - Sarcina


Rods - Bacillus


Curved rods - comma shaped - Vibrios


Spirals - Spirrilum, Spirochaetes


Filamentous - Actinomycetes


Rods wth tapering ends - Fusobacterium


Rods with bifercated ends - Bifidobaterium


Cells without cell wall do not have fixed shape, these are Mycoplasma.


You will get this information in any basic microbiology book or in wikipedia

What sizes and shapes do bacteria have?
they are tiny in size and could be of various shapes like round,cylindrical,snails like,,,,,,,,,,tiny droplets.
Reply:Bacilli (sing. bacillus) are elongated, like a rod (baculus in Latin).





Cocci (sing. coccus) are round, like a coconut.





Spirilla (sing. spirillum) are spiral.





When they come in a conga line, they are prefixed "strepto-" so "streptococci" means several spherical ones lined up.





When they come in clusters like grapes, they are prefixed "staphylo-" so "staphylococci" means a cluster of the round ones.





They go from 0.1 micrometres (that is, 0.1 of a millionth of a metre) to 600 micrometres. Cocci are smaller than bacilli, and these are smaller than or equal to spirilla.