Explain the barrier function in the cornea, Biology

Assignment Help:

Explain the barrier function in the cornea.

Barrier Function:

It is the first line of barrier between the external environment and the corneal stroma. The superficial epithelial cells are encircled by tight junctions (zonula occludens).

These superficial epithelial cells serve as semi-pernieable high resistance (12- 16kQ) membrane. It prevents niovement of fluid from tear to stroma. It is useful for maintenance of epithelial barrier. The maintenance is done by mitosis of basal cells and migration of new basal cells from the limbal stern cells. So the corneal epithelium is maintained by a balance among the process of centripetal cell migration (120pm/wk), mitosis, and shedding of superficial cells. The XYZ hypothesis of corneal epithelial maintenance by Thoft and Friend is X+Y=Z. The limbal epithelium has the highest mitotic rate followed by peripheral cells and central cells have the lowest mitotic mte.


Related Discussions:- Explain the barrier function in the cornea

Protective role and metal chelating ability - nicotinic acid, Define Protec...

Define Protective role and Metal chelating ability? Protective role: Nicotinic acid is vital to the normal functioning of the skin intestinal tract and nervous system. It p

What is the basic structure of a virus, What is the basic structure of a vi...

What is the basic structure of a virus? Viruses are constituted of genetic material (DNA or RNA) covered by a protein capsule also called as a capsid. Some viruses, like HIV, h

Viral genome, describe the different types of genomes that viruses can have...

describe the different types of genomes that viruses can have

Briefly discuss the salmonella food infection, Briefly discuss the Salmonel...

Briefly discuss the Salmonella food infection. • Salmonella food infection is caused by Salmonella gastroenteritis. Transmitted by faecal contamination of foods. In

Effect on microbial ecology and food spoilage of ph, Q. Effect on Microbial...

Q. Effect on Microbial Ecology and Food Spoilage of pH? The acidity of a product plays an important role in deciding the type microflora present in food and the rate and type o

Which animals make cutaneous respiration, Q. Which animals make cutaneous r...

Q. Which animals make cutaneous respiration? Adult amphibians and Terrestrial annelids make cutaneous respiration in amphibians there is also pulmonary respiration, the thin sk

What body system hiv impairs, Given that most AIDS victims die from overwhe...

Given that most AIDS victims die from overwhelming infections or rare types of cancer, what body system do you think HIV (the AIDS virus) impairs?

Define the structure of vitamins, Define the Structure of Vitamins? Fo...

Define the Structure of Vitamins? For your convenience, however, we have given the structures of these vitamins here in the text. Look at Figure which illustrates the fat-solu

What are the vessels that carry blood to the kidneys, Q. What are the vesse...

Q. What are the vessels that carry blood to the kidneys? Is this blood venous or arterial? The renal arteries are ramifications of the aorta and so the blood filtered by the ki

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd