Question

Where is Pseduostratified Ciliated Columnar found?

Group of answer choices:

Lining of bladder, urethra, ureters

Lines most of the respiratory tract

Ends of Long Bones, costal cartilages of ribs cartilages of nose, trachea

Lines the Kidney tubules

IV discs, pubic symphysis, discs of knee joints

Answer 1

Where is pseudostratified ciliated columnar epithelium found?

Answer : lines most of the respiratory tract.

Explanation : Stratified epithelium literally means multilayered epithelium. It can be stratified squamous epithelium, stratified columnar epithelium or stratified cuboidal epithelium.

In pseudostratified epithelium, the epithelium is made up of single layer of cells but due to the nuclei of the cells being arranged at different levels, it gives the appearance of being multilayered or pseudostratified epithelium. If this epithelium is made up of single layer of columnar cells and has cilia then it is called pseudostratified ciliated columnar epithelium. It is classically found in the linings of the trachea and upper respiratory tract of respiratory system. It secretes the mucous as well as clear out the mucous and other harmful particles from the respiratory tract. It protects the respiratory tract by the ciliary movement.

Other options:

Linings of bladder, urethra, ureters are made up of transitional epithelium also known as urothelium. It can expand and contract as and when needed, especially useful in temporarily storing the releasing the stored urine. In transitional epithelium, the cells are connected with tight junctions which prevents the pathogens from the urine to enter the blood stream.

Ends of the long bones, costal cartilage of ribs, cartilages of nose, trachea are lined by hyaline cartilage. It provides smooth surfaces for joint movements without any friction between the bones involved in the joint.

The kidney tubules are lined by cuboidal epithelium in most parts. The proximal convoluted tubule is lined by cuboidal epithelium with brush border which increases the surface area for absorption.

IV discs, pubic symphysis, discs of knee joint are lined by fibrocartilage. It is a dense connective tissue which protects the joints from injuries as well as helps in healing by fibrosis (scarring) after an injury.