Pleomorphic organisms are :
**Core Concept**
Pleomorphic organisms are those that exhibit multiple forms or shapes, often in response to environmental changes or during different stages of their life cycle. This phenomenon is commonly observed in certain types of bacteria and protozoa, where the morphology can vary significantly.
**Why the Correct Answer is Right**
Pleomorphic organisms often display a range of morphological features, including variations in size, shape, and arrangement of cells. For example, some bacteria can change from a spiral shape to a coccoid shape in response to changes in temperature, pH, or nutrient availability. This flexibility in morphology allows pleomorphic organisms to adapt to different environments and survive under various conditions.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it does not accurately describe the characteristic of pleomorphic organisms.
**Option B:** This option is incorrect as it is too broad and does not specifically refer to the change in morphology exhibited by pleomorphic organisms.
**Option C:** This option is incorrect as it is not a characteristic of pleomorphic organisms.
**Clinical Pearl / High-Yield Fact**
Pleomorphic organisms can be challenging to identify using traditional microbiological techniques, as their changing morphology can make it difficult to distinguish them from other microorganisms.
**Correct Answer: C. Pleomorphic bacteria such as Corynebacterium diphtheriae and Bacillus anthracis.**