bench definition, bench meaning | English dictionary. bench. n an apparatus for experimentation in optics, typically consisting of an adjustable arrangement of light source, lenses, prisms, etc. bench.
3 Principal characteristics of cells that make up epithelium. -Cells are closely apposed-they adhere to one another via specialized cell junctions-Exhibit both structural and functional polarity-Epithelium creates a selective barrier between the external environment and the underlying connective tissue.î î î.Cells are closely apposed-they adhere to one another via specialized cell junctions-Exhibit both structural and functional polarity-Epithelium creates a selective barrier between the external environment and the underlying connective tissue. î î î.
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).