Which term describes coiled, corkscrew-shaped bacterial cells that cause Lyme disease?

• A. Spirilla
• B. Cocci
• C. Bacilli
• D. Vibrios

Answer: (A)

Bacteria that are coiled and corkscrew-shaped are described as spirilla. This spiral form helps distinguish them from other shapes: cocci are spherical, bacilli are rod-shaped, and vibrios are curved rods. Lyme disease is caused by Borrelia burgdorferi, which is a spiral organism, so the term that best fits the description given in the question is spirilla. The key visual cue is the twisty, spiral form, not a straight rod or a simple curve.