Question

What are goblet cells? Where are they located? What are the uses?

Answer 1

Hint: The shape of the cell is in its name. Like a ‘goblet’ full of fluid these cells help in keeping internal surfaces of respiratory, digestive, and reproductive organs moist and slimy. This is due to their mucus secretion.

Complete answer:
Goblet cells are cup or ‘goblet’ shaped simple columnar epithelial cells responsible for producing and secreting mucin. In the intestine, these cells arise from pluripotent stem cells in the intestinal crypts. These cells are highly polarised with the nucleus and organelles restricted to the cell base while the apical surface facing the intestine lumen is projected in the finger like microvilli to increase the surface area for optimising its secretory function.
These cells are found in all our organs which secrete mucus. This includes our intestines (especially large intestines with their number increasing towards the rectum), respiratory tracts and urogenital epithelium, ocular (conjunctiva) and gallbladder epithelia.
Goblet cells produce and secrete mucus, a gel composed of mucin water and inorganic salts. Mucus layer is our first barrier against invading germs and foreign particles. Currently goblet cells are also suggested to be involved in immunoregulation. Goblet cells employ merocrine (proteins are secreted via the secretory pathway) method of secretion under normal circumstances and apocrine (secretory product is bud off from the cell in a vesicle without being released) method of secretion in case of stress.

Note: Goblet cells are very important for maintaining our mucus layer, but more is not always good. Unnatural increase in goblet cell numbers results in pathogenic conditions such as asthma, chronic obstructive pulmonary disease while decrease in these cells in intestines is seen in ulcerative colitis respectively.