Final answer:
Mucous threads are the component of urine that may rise to a plane just below the coverslip and appear in a different plane of focus than other elements.
Step-by-step explanation:
The component of urine that may rise to a plane just below the coverslip and is in a different plane of focus than the other elements is Mucous threads.
Mucous threads are long, stringy strands of mucus that can be present in urine and may appear on a wet-mount slide. They can sometimes be seen in the field of view on a microscope slide, just below the coverslip, when examining a urine sample.