Gall bladder is lined by (AIIMS Nov 2012)
|A||Brush bordered columnar epithelium|
|B||Striated columnar epithelium|
|C||Pseudostratified columnar cells|
|D||Ciliated columnar cells|
Brush bordered columnar epithelium
2. When microvilli are of same height & arranged regularly, they are termed as striated border, as observed in small intestine
3. If they are of irregular height, they will constitute the brush border as seen in gall bladder and proximal convoluted tubules of kidney
4. There are several thousand microvilli present on the apical surface of a single cell in human small intestinal cells.
5. Microvilli also occur in sensory cells of the inner ear (as stereocilia), in the cells of taste buds, and in olfactory receptor cells.
6. Motile cilia are found in the lining of the respiratory tract like trachea, where they sweep mucus and dirt out of the lungs.
7. In the oviducts, the beating of cilia moves the ovum from the ovary to the uterus.
8. Genetic mutations compromising the proper functioning of cilia can cause chronic disorders such as primary ciliary dyskinesia (PCD) - Kartagener syndrome ( Immotile cilia syndrome, leading to situs inversus, recurrent respiratory infections, infertility).
9. In addition, a defect of the primary cilium in the renal tube cells can lead to polycystic kidney disease (PKD).