•Mr. Ravi kumar•B.S.C (N)1st year•Chirayu college of nursing

MORPHOLOGY OF BACTERIA

Morph means ‘’Form’’ and ‘’ology’’ means the study.

Bacteria form a large group of unicellular prokaryotes that do not contain a nucleus and other membrane bound organelles.

They were first observed by antony van leeuwenhoek in 1676 using a single lens microscope of his own design.

he called them ‘animalcules’ and published his observations in a series of letters to the royal society of london.

The name bacterium was introduced much later by Christian Gottfried Ehrer berg in 1838.

Typically a few micrometers in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.

SIZE OF BACTERIA- bacterial cells are about one tenth the sizes of

eukaryotic cells and are typically 0.5- 5.0 micrometers in length.0.2-1.5 micrometers in diameter.

Some bacteria may be even smaller, but these ultra microbacteria are not well-studied.

SHAPE OF BACTERIA/ MORPHOLOGICAL TYPES:-1.Cocci- these are spherical or oval cells.Micrococci – occur singlyDiplococci- occur in pairStreptococci- cocci that occur in chainsStaphylococci- occurs in bunchesTetrad- cocci that occurs in fourSarcina- cocci that occur in group of eight

2. bacilli- these are rod or stick- shaped cells.On the basis of arrangement of the individual

organism they may be:- microbacill- bacilli that occur singly.Diplococci-bacilli that occur in pairs.Streptobacilli- bacilli that occur in chains.

Palisade arrangement- bacilli lined side by side like matchsticks and at angles to one another.

Eg- corynebactrium diphtheriaea causing diptheria comma- shaped- bacilli that are curved and look

like a commaEg- vibrio cholera causing choleraSpirillum- bacilli which are coiled like a cork-

screw through 1-5 complete turns eg- spirillum minus causing rat bite fever.

3. coccobacillus- these are the bacteria which are intermediate to coccus and bacillus eg- brucella

4. spirochetes- they are relatively longer, slender, flexous, non- branched microorganism of spiral shape having several coils eg- treponema pallidum causing syphilis