At the chemical level, the DNA of prokaryotic cells, which have no nuclear membranes, and that of eukaryotic cells, which have separate, membrane-enclosed nuclei, is identical. DNA is a long, double-stranded molecule containing a backbone of repeating, alternating sugar and phosphate units.
Simple cuboidal epithelium is a type of epithelial tissue found in the body. It is a single layer thick and made of cube-shaped cells. This type of tissue is found lining parts of the body such as the kidney tubules and walls of respiratory bronchioles.
Stratified cuboidal epithelium. 1  consists of two or three layers of cuboidal cells. 2  is found lining larger excretory ducts such as those of salivary glands, sweat glands and pancreas. 3  does not have an absorptive or secretory function but provides a more robust lining than that of simple epithelium.