What type of bacteria is known for its rod shape?

Bacilli are the type of bacteria that are characterized by their rod shape. This morphology is a defining feature of bacilli, which can vary in size and arrangement but are fundamentally recognized for their elongated, cylindrical form. This rod-like structure allows bacilli to thrive in various environments and contributes to their diverse functions and roles in both health and disease.

In contrast, cocci are spherical-shaped bacteria, spirilla exhibit a spiral shape, and vibrio are comma-shaped bacteria. Each of these types has distinct characteristics that differentiate them from bacilli, but it's the rod shape specifically that makes bacilli the correct answer to this question. Understanding these distinctions is crucial for identifying bacteria, knowing their implications in various settings, such as clinical diagnostics, food safety, and environmental microbiology.