Granules

Definition

Granules are small particles or droplets within cells that store substances such as nutrients, pigments, or secretory products. In microbiology, they can be found in both prokaryotic and eukaryotic cells.

5 Must Know Facts For Your Next Test

1. Granules in Gram-positive bacteria often contain storage materials like glycogen and polyphosphate.
2. In microbial biochemistry, granules can help identify microorganisms based on their stored substances.
3. Some immune cells have granules that release enzymes and other chemicals during hypersensitivity reactions.
4. Granules are visible under a microscope and can be stained for better visualization.
5. The presence of certain types of granules can indicate specific diseases or infections.

Review Questions

• What types of substances are typically stored in bacterial granules?
• How can the presence of granules aid in the identification of microorganisms?
• What role do granules play in hypersensitivity reactions?

Related terms

Endospore: A resistant asexual spore that develops inside some bacteria cells.

Inclusion Body: Aggregates of stable substances, usually proteins, found within the cytoplasm or nucleus.

Vesicle: A small membrane-bound sac that stores and transports substances within a cell.