Write short notes on Structure and Function of Epithelial tissue.
Answers
FUNCTION OF EPITHELIAL TISSUE.
All materials entering or leaving the body must ultimately cross at least one layer of epithelial tissue. In general, four functions may be attributed to epithelial tissues: (1) protection of the underlying tissues, (2) absorption, (3) secretion, and (4) reception of sensory stimuli.
STRUCTURE OF EPITHELIAL TISSUE
Cells of epithelial tissue are scutoid shaped, tightly packed and form a continuous sheet. They have almost no intercellular spaces. All epithelia is usually separated from underlying tissues by an extracellular fibrous basement membrane. The lining of the mouth, lung alveoli and kidney tubules are all made of epithelial tissue. The lining of the blood and lymphatic vessels are of a specialised form of epithelium called endothelium.
Epithelial tissue, the type of tissue that lines the surfaces and cavities of your body's organs, is no different. Epithelial tissue is like the brand name Lego: Lego has differently sized and shaped blocks, and epithelial tissue has differently sized and shaped cells. Lego blocks can be arranged into differently shaped structures, and epithelial cells can be arranged into differently shaped structures as well.
Regardless of the shape, size, or arrangement of the cells, they are still a type of, or part of, epithelial tissue, just like all our differently sized, shaped, and arranged plastic bricks are still Legos