Differences between Pneumococcus and Viridans streptococci

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S.N.	Properties	Pneumococcus	Viridans streptococci
1	Morphology	Lanceolate or flame-shaped	Round/oval
2	Arrangement	Gram-positive cocci in pairs	Gram-positive cocci in long chains
3	Capsule	Present	Absent
4	On blood agar	Draughtsman or carom coin colony	Convex shaped colony
5	Liquid medium	Uniform turbidity	Granular turbidity
6	Bile solubility	Soluble in bile	Insoluble in bile
7	Inulin fermentation	Fermenter	Non-fermenter
8	Optochin	Sensitive	Resistant
9	Mice Pathogenicity	Pathogenic	Non-pathogenic
10	Quellung Test	Positive	Negative
11	Hemolysis	Alpha-hemolytic (under aerobic conditions) or Beta-hemolytic (under anaerobic conditions)	Alpha hemolytic or non-hemolytic
12	Pathogenesis	Causes pneumonia	Causes mainly oral infections