Inclusions have been found to contain ___________ .


a. DNA
b. sulfur globules
c. dipicolinic acid
d. tubulin

Verified step by step guidance

1. Step 1: Understand what inclusions are in microbiology. Inclusions are reserve deposits found within the cytoplasm of prokaryotic cells, often serving as storage sites for nutrients or other substances.
2. Step 2: Review the options given: (a) DNA, (b) sulfur globules, (c) dipicolinic acid, and (d) tubulin. Consider which of these substances are typically stored or found as inclusions in bacterial cells.
3. Step 3: Recall that DNA is generally found in the nucleoid region, not as inclusions. Tubulin is a eukaryotic cytoskeletal protein, not found in prokaryotic inclusions.
4. Step 4: Recognize that dipicolinic acid is a component of bacterial endospores, not inclusions. Sulfur globules, however, are known to be stored as inclusions in some bacteria, serving as an energy reserve.
5. Step 5: Conclude that inclusions have been found to contain sulfur globules, making option (b) the correct choice.

Key Concepts

Bacterial Inclusions

Inclusions are reserve deposits found within bacterial cytoplasm that store nutrients or other substances. They serve as energy reserves or structural components, varying in composition depending on the bacterial species and environmental conditions.

Sulfur Globules as Inclusions

Sulfur globules are a type of inclusion found in some bacteria, especially sulfur-oxidizing species. These globules store elemental sulfur, which bacteria can use as an energy source during metabolism.

Dipicolinic Acid and Endospores

Dipicolinic acid is a chemical found primarily in bacterial endospores, not inclusions. It helps stabilize the spore's DNA and proteins, contributing to spore resistance but is not stored in cytoplasmic inclusions.