Kidney cortex
This very tall image shows almost the entire thickness of
the kidney. Your goal is to find and learn to recognize simple
squamous epithelium on a slide similar to this. The easiest place
to find this tissue is the glomerular capsule (don't worry, you
don't have to know what that is to find and recognize the tissue).
In the top one third of the image you can see circular structures
surrounded by a thin white space. The arrows point to two of
these structures. The white space is the inside of the glomerular
capsule, and the simple squamous epithelium forms a thin layer
around the outside of the white space.
Kidney cortex
In this image the arrow is again pointing to a glomerular capsule. (The rectangle shows which part of this image has been enlarged and shown below.) At this magnification you can't see the tissue yet, but you will get a better idea of where to look.
Kidney cortex
This image
is the area that was enclosed in a rectangle in the previous
image. The dark purple spots are the nuclei of cells, and the
cytoplasm is stained a dark pink color. The glomerular capsule
is marked with an asterisk (*). Look around the outer edge of
the capsule and you will see some short, thin, dark lines. These
are the nuclei of the simple squamous epithelial cells. There
is a simple squamous epithelial cell nucleus just to the right
of the asterisk. Kidney cortex
The arrows in the image point to the nuclei of simple squamous
epithelial cells. This image was made from a thin section of
the kidney at the same magnification as the previous image (400X).
It is about one-fifth to one-tenth the thickness of the slides
used to make the top three images on this page.
Thin sections allow us to see more detail, but they are usually
lighter because there is not as much tissue to absorb stain.
Another difference between this slide and the previous three
is that the glomerular capsule is much harder to see here. In
thick sections tissues shrink more during processing, which leaves
bigger spaces between the cells. The space in the glomerular
capsules that you see in the top three images is not present
in living tissue. This thin-section image is more life-like because
it didn't shrink as much and there aren't such large spaces between
cells. But the one advantage of the shrinkage in the thick sections
is that it gives you an easy landmark for finding the simple
squamous epithelial tissue. You will usually be using thick section
slides in lab.