Which type of bacterial arrangement forms a cube?

Tetrads refer to a specific arrangement of cocci bacteria that form groups of four. This arrangement occurs when the bacterial cells divide in two planes, leading to the characteristic cube shape. Since there are two divisions happening at right angles to each other, the resulting structure is a cube, with four cells occupying the corners. Understanding tetrads is important in microbiology as it can help identify certain species of bacteria based on their physical arrangement.

In contrast, chains refer to a linear arrangement of cells that come from division in one plane, such as in streptococci. Diplo- indicates pairs of cells resulting from division in one plane, and staphylococci describe clusters or grape-like arrangements formed from division in multiple planes, but not specifically in a cubic formation. Each of these arrangements plays a distinct role in the classification and identification of bacteria, with tetrads being unique in forming a cubic structure.