What organism forms a small, fuzzy-edged colony with an umbonate center on blood or chocolate agar?
A)Eikenella corrodens
B)Staphylococcus aureus
C)Escherichia coli
D)Streptococcus pyogenes

Question

Quizplus · Accepted Answer

E.corrodens fits multiple descriptive categories of colonial morphology because it forms a small, fuzzy-edged colony with an umbonate center on blood or chocolate agar.Staphylococcus aureus forms white, convex, b-hemolytic colonies on blood agar.E.coli forms large, mucoid, grayish, hemolytic colonies on blood agar.Streptococcus pyogenes forms a pinpoint colony, surrounded by a wide, deep zone of b-hemolysis.

What Organism Forms a Small, Fuzzy-Edged Colony with an Umbonate