Kidney's are an essential component of the body, being responsible for maintaining electrolyte balance within the body, in addition to the pH balance. Beyond those functions, the kidney also processes almost 200L of blood daily; removing organic waste (e.g. byproducts of metabolism) and excreting these through the urinary system. Without the kidney(s) we would struggle to exist which is where dialysis comes into play, thankfully as we have two kidney's most will not need to undergo that horrible process. The Kidneys also serve other processes, including aiding in the re-adsorption of glucose and other molecules.
The following images (below) were captured using pre-prepared microscope slides which were acquired from a university collection. The images (from memory) were of a rat's kidney however I could be incorrect.
All of my “under the microscope” images are taken in a similar manner, and using the below equipment. In this case, focus stacking was conducted by capturing a video of the subject as I move through the planes of focus, and then software pulled the images out of that video and focus stacked them into the images below;