Start by creating a new file named âweb_server.jsâ. Insert the following code into the file and save it. To start the server, type the command shown below. If everything works properly, you will see a message that the server is listening.
Epithelia are classified on the basis of the number of cell layers and the shape of the cells in the surface layer. * If there is only one layer of cells in the epithelium, it is designated simple. * If there are two or more layers of cells, it is termed stratified.* Cells in the surface layer are, as a rule, described according to their height as squamous (scale-or plate-like), cuboidal or columnar.Examine each of the basic types of cells so that you get an understanding for how the layers are organized and how they are named.pithelia are classified on the basis of the number of cell layers and the shape of the cells in the surface layer. * If there is only one layer of cells in the epithelium, it is designated simple. * If there are two or more layers of cells, it is termed stratified.
Epithelial Tissue. Epithelial tissues come in three basic types: squamous, cuboidal and columnar. These three types of tissue are seen in either simple (only one cell layer thick) or stratified (many cells in thickness) arrangements.imple Columnar Epithelium. This is a cross section through the small intestine. The tall, vertical cells seen at the top of the tissue are columnar cells (one is shown-red arrow), which make up simple columnar epithelium (the cells at the bottom of the image are connective tissue, which will be discussed later).