Which control mechanim(s) are physical mechanisms? Select all correct options Pasteurization Degermation Refrigeration Desiccation

Degermation, refrigeration, and desiccation are physical control mechanisms.<br /><br />* **Degermation** is the physical removal of microbes from a limited area, such as swabbing skin with alcohol before an injection.<br />* **Refrigeration** uses low temperatures to slow microbial growth and reproduction.<br />* **Desiccation** or drying inhibits growth because metabolism requires liquid water.<br /><br />Pasteurization uses heat, but it's considered a *primarily* chemical control mechanism as the heat alters the chemical structure of key microbial molecules. While it involves a physical factor (temperature), the core mechanism of action is chemical change within the microbes.<br />