Final answer:
In microbiology, specimens can be rejected due to improper handling during transport or storage, with strict preservation protocols like ultra-low temperature freezing being essential.
Step-by-step explanation:
Criteria for rejection of specimens in microbiology include improper handling during transport or storage. It is essential to maintain appropriate conditions throughout the processing of specimens to ensure their integrity for accurate analysis. For instance, microbial cultures and medical specimens may need to be frozen at ultra-low temperatures, as low as -70 °C or colder, to preserve their viability. If these protocols are not strictly adhered to, such as maintaining sterility or ensuring correct temperatures, specimens may become compromised and, therefore, subject to rejection.