Which of the following best describes an umbonate bacterial colony?

• A. A colony with a raised, dome-shaped center
• B. A colony with a flat and even surface
• C. A colony with a wrinkled or irregular surface
• D. A colony with a spreading, thin edge

Answer: (A)

Verified step by step guidance

1. Understand that bacterial colony morphology describes the visible characteristics of colonies grown on solid media, which helps in identifying and differentiating bacterial species.
2. Recognize that the term 'umbonate' specifically refers to the shape of the colony's elevation or center.
3. Recall that an 'umbonate' colony has a raised center that is dome-shaped, resembling a small bump or knob in the middle of the colony.
4. Compare this with other colony shapes: a flat colony has an even surface without elevation; a wrinkled colony has an irregular, folded surface; and a spreading colony has thin edges that extend outward.
5. Conclude that the best description of an umbonate colony is one with a raised, dome-shaped center.