The library

341 reference cards, one search away.

Every organism and topic in PetriKey - 182 organisms and 159 topics across eight categories. Search, browse by category or gram stain, or walk the list A to Z. All free.

New to the material? The study guides cover the stains, tests, and branches these cards assume you already know.

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Browse A to Z

The full list, split into eight alphabetical pages. Every card in the library is on exactly one of them.

A to B (47)C to D (52)E to G (38)H to L (54)M to O (41)P to R (35)S to T (50)U to Z (24)

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Bacteria (78)Viruses (48)Fungi (19)Parasites (37)Lab & diagnostics (45)Antimicrobials (36)Concepts (46)Diseases & syndromes (32)

Browse by gram stain and shape

Gram-positive (23)Gram-negative (42)Gram-positive cocci (11)Gram-positive rods (12)Gram-negative cocci (3)Gram-negative rods (20)Gram-negative coccobacilli (10)Gram-negative curved rods (5)

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Bacterium

Staphylococcus aureus

Gram-positive cocci in clusters

Gram +

Bacterium

Streptococcus pyogenes

Group A beta-hemolytic streptococcus

Gram +

Bacterium

Escherichia coli

Gram-negative lactose-fermenting rod

Gram −

Bacterium

Pseudomonas aeruginosa

Oxidase-positive nonfermenting rod

Gram −

Bacterium

Neisseria meningitidis

Gram-negative diplococci

Gram −

Bacterium

Mycobacterium tuberculosis

Acid-fast rod

Fungus

Candida albicans

Yeast with germ-tube clue

Virus

Influenza virus

Segmented negative-sense RNA virus