Final answer:
White-nose syndrome is a fungal disease affecting little brown bats in North America, caused by the fungus Pseudogymnoascus destructans. This pathogen, likely introduced from Europe, has a significant impact on bat populations and threatens endangered species.
Step-by-step explanation:
The student asked about the biological organization of little brown bats and their threat from white-nose syndrome. This disease is caused by the fungus Pseudogymnoascus destructans, which was likely introduced from Europe to North America, where it infects cave-hibernating bats. White-nose syndrome has been devastating to bat populations, including the endangered species such as the Indiana bat and the Virginia big-eared bat. Because this pathogen forms mycelia with cells that have a nucleus and cell walls, it is classified as a fungus rather than a bacterium.