Final answer:
DNA, including blood, semen, and other bodily fluids, should be stored at controlled temperatures to maintain viability. For semen, specific steps are taken to cool and freeze it properly. DNA and other samples can be preserved at ultra-low temperatures using techniques like dry ice or liquid nitrogen freezing.
Step-by-step explanation:
When it comes to preserving and storing DNA, including blood, semen, and other bodily fluids, it is important to keep them in a controlled environment to maintain their viability. In the case of semen, it should be cooled gradually to 5°C and held at that temperature for several hours before freezing to equilibrate with the extender. The frozen semen is then stored in liquid nitrogen refrigerators.
For general preservation of DNA, it can be frozen and stored at ultra-low temperatures, such as -70°C or lower. This can be achieved using dry ice or liquid nitrogen tanks that maintain temperatures below -196°C.
It is crucial to note that the method and specific time before impounding in a fridge/freezer may vary depending on the purpose and protocols followed in different scenarios. It is best to consult specific guidelines provided by professionals in the field or the corresponding laboratory.