WHAT TISSUE IS THIS? – 2
This image is a larger magnification of a region similar to that outlined in the figure on the previous page.
Once again, the three regions are present.
The upper region is empty; it must be a body cavity or the external surface of the body.
The middle layer is well stained, contains many cells, considering the amount of nuclei that can be seen in it.
The lower layer has fewer cells, judging by the amount of nuclei. Observe that their cells are separated from each other by an extracellulr space that contains a filamentous material.
Are these last two layers formed by the same type of tissue or by different tissues?
See below a more detailed analysis of these regions:
Once again, the three regions are present.
The upper region is empty; it must be a body cavity or the external surface of the body.
The middle layer is well stained, contains many cells, considering the amount of nuclei that can be seen in it.
The lower layer has fewer cells, judging by the amount of nuclei. Observe that their cells are separated from each other by an extracellulr space that contains a filamentous material.
Are these last two layers formed by the same type of tissue or by different tissues?
See below a more detailed analysis of these regions:
| Main features of the layer | Middle layer with many cells | Lower layer with separated cells |
| Does it coat some structure? | yes, it coats some other tissue | no |
| Do their cells stand closely together? | yes | no, they are apart from each other |
| Extracellular material? | not visible | yes, a lot |
| does it have blood vessels? | no | yes |
The middle region has manny features of a covering epithelial tissue, unlike the lower strip, which has characteristics of a connective tissue.
In fact, it makes a lot of sense, since epithelial tissues are always supported by connective tissue.