Final answer:
The temperature for sample preservation using cooling methods depends on the type of sample. Bacterial cultures and medical specimens are often stored at ultra-low temperatures below -70 °C. Refrigeration preservation typically involves maintaining temperatures between 0 °C and 7 °C.
Step-by-step explanation:
When cooling is used for sample preservation, the temperature that should be maintained depends on the specific sample and its requirements.
For bacterial cultures and medical specimens, ultra-low temperatures of -70 °C or lower are often used for long-term storage or transport. This can be achieved by storing the samples on dry ice in an ultra-low freezer or in liquid nitrogen tanks that maintain temperatures lower than -196 °C.
For refrigeration preservation, temperatures between 0 °C and 7 °C are typically maintained. This range inhibits microbial metabolism, slowing the growth of microorganisms and helping preserve products like food or medical supplies.