When trimming tissue, the sides, tips, and bottom are shaped into which form?

When trimming tissue for histopathologic examination, the goal is to create an optimal geometry that facilitates uniform processing and sectioning. The correct shape is a truncated pyramid. This design allows for the tissue to be adequately exposed during processing, ensuring that the most relevant portions of the tissue specimen are accessed and evaluated during the microscopic examination.

The truncated pyramid shape provides several advantages: it offers larger surface area for fixation and embedding, minimizes the risk of losing important tissue details during cutting, and enhances the stability of the specimen while being sectioned, which is crucial for obtaining thin slices for slides. This precise trimming method helps pathologists obtain better, more consistent results.

In contrast, other shapes like a square or circle would not provide the ideal exposure or support needed for effective sectioning, while a triangle might introduce complications in obtaining even, consistent thickness in tissue slices. Thus, shaping the tissue into a truncated pyramid is the most effective practice in histopathology.