What type of cell-surface characteristic helps an epithelial tissue helps the tissue to expand? Which type of epithelial tissue is found forming the walls of the air sacs in the lungs? What is the function of this tissue there? Which type of epithelial tissue is found forming the Walls of many of the kidneys tubules, as well as glands? What is the function of this tissue there? Which type of epithelial tissue if found lining many of the airways of the respiratory tract? What type of cell surface characterizes this epithelial tissue? What is the function of this tissue there? Which type of epithelial tissue if found in the small intestine? What type of cell surface characterizes this epithelial tissue? What is the function of this tissue there? Which type of epithelial tissue if found forming the outer layers of skin? What type of cell surface characterizes this epithelial tissue? What is the function of this tissue there? Which type of epithelial tissue if found lining the urinary bladder? What type of cell surface characterizes this epithelial tissue? What is the function of this tissue there? Solution Answers: Types of epithelial tissues: 1. (a) Simple sqaumous epithelium lines the air sacs or alveoli of the lungs. (b) Simple squamous epithelium in the alveoli allow oxygen from the air to enter the blood in the capillaries of the lungs. carbon dioxide is also eliminated from the body through the simple squamous epethelial cells of the lung air sacs. 2. (a) Simple cuboidal epithelium (b) The cells perform secretion and absorption in the kidney tubules and glandular ducts. 3. (a) Ciliated pseudostratified columnar epithelium are found in the airways of the respiratory tract. (b) They are characterized by the presence of cilia and secretion of mucous which collect foreign materials and help to cough or sneeze them out. (c) It helps to moisten and protect the airways by acting as a protective barrier pathogens and foreign antigens through mucociliatory action. 4. (a) Intestinal epithelium forms the lining of both small and large intestines. It is composed of simple columnar epithelial cells. (b) These cells are characterized by the presence of circular and transverse folds, villi and microvilli. (c) It acts as a protective barrier to foreign antigens and toxins and also acts as a selectivity filter to facilitate the uptake of dietary nutrients. 5. (a) Stratified squamous epithelium is found on the surface of skin. (b) They may be keratinized or non keratinized. (c) Its main function is protection from wear and tear. 6. (a) Transitional epithelium (b) They may be cuboidal or columnar. When the tissue compressed, the cells become stretched. During such conditions, they appear to be irregular and squamous. (c) They can stretch and allow for the accommodation and storage of fluid in the urinary bladder. It also acts as a barrier between the lumen and the blood stream..