Final answer:
During pregnancy, the normal BUN range may lower slightly from the typical 6-20 mg/dL due to increased renal function. Elevated BUN levels can signify potential kidney issues or dehydration. Key kidney structures contribute to these processes and must be assessed if BUN is high.
Step-by-step explanation:
The normal range of blood urea nitrogen (BUN) during pregnancy generally lowers compared to non-pregnant levels due to increased plasma volume and renal function. Normal BUN levels are typically between 6 and 20 mg/dL for adults, but they may drop slightly during pregnancy. Elevated BUN levels could indicate various conditions such as dehydration, kidney disease, or other factors affecting kidney function. Key structures like Bowman's capsule and the calyx play vital roles in kidney filtration and urine formation, respectively. If BUN levels are found to be high, it's important to assess kidney function and other related parameters closely.