Question

multiple choice question
which characteristic makes mycoplasmas pleiomorphic?

their external s - layer
they lack a cell wall
their plasma membranes
their flagella

Explanation:

Mycoplasmas are pleiomorphic (having multiple forms) primarily because they lack a cell wall. A cell wall typically provides a fixed shape to a cell; without it, mycoplasmas can change their shape easily. The external S - layer is not a characteristic of mycoplasmas related to their pleiomorphism, their plasma membranes alone don't cause pleiomorphism, and they generally lack flagella, and flagella are related to motility, not shape variation.

Answer:

B. They lack a cell wall