What are Epithelial Cells?

Epithelial cells are a group of tightly compressed cells that layers itself on the internal and external surfaces of bodily organs and other surfaces found in the body. As a collective term, these cells are also referred to as a tissue called epithelium. These cells are also the primary composition of human skin.

The basic function of epithelial cells is to provide a protective layer for the organ they enclose. Cells of this type in the digestive system also can absorb nutrients that the body needs during the digestion process. They can also aid in the secretion of enzymes and hormones, as well as the excretion of unwanted byproducts, especially when located in areas such as the kidneys and sweat glands. Epithelial linings along the lungs help disseminate the oxygen in all parts of bodies. Special epithelial tissues around the sense organs such as the eyes, nose and tongue are made with nerve endings to heighten sensitivity.

These cells are categorized as either lining or glandular ephithelium cells. Lining epithelials further protect the organs by coating the cell’s basement membrane, another protecting sheet that prevents foreign bodies from invading the healthy organs. Glandular epithelial cells, on the other hand, coat the glands, such as the sweat and mammary glands.

Lining epithelial cells are further classified as simple or stratified epithelials. The simple type has only one layer of cells, and the stratified kind is composed of several cell layers, ranging from three to seven layers. Stratified cells are usually found on organs that can experience heavy attacks from chemical reactions or foreign bodies, such that the organs are not affected even if one layer of epithelial cells is destroyed. An epithelial cell can also take various shapes, depending on its location and function: flat, cube-like or column-shaped.

Epithelial cells are usually constructed to not have any blood vessels, so no physical pain is experienced when they are exfoliated and regenerated constantly, not just from the skin, but from all organs that have epithelia. Urine can be a vehicle for these cells to be excreted out of the body, which is why it is normal for these cells to be microscopically observed during urinalysis. Elevated amounts of epithelial cells, however, can indicate problems such as bladder or urinary tract infection. Urine that is unusually cloudy and darker-colored might cause some concerns and a need for a thorough urinalysis.

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Post 4

I recently had a painful scratch on my cornea, and my eye doctor told me about the epithelium. This is the outermost area of the cornea. It blocks water, bacteria, and dust from entering the eye, and it absorbs nutrients and oxygen from tears.

Because the epithelium contains thousands of nerve endings, the cornea is highly sensitive to scratching or rubbing. That is why I felt so much pain when I ran into a thorny blackberry bush on the lawnmower and received the scratch.

He put anti-inflammatory eyedrops in the affected eye to prevent scarring. He also gave me some pain pills to take.

Post 3

I am glad that epithelial cells don’t have blood vessels, because I exfoliate a lot, and I feel no pain. I have particularly dry skin, and I use a self tanner, so I have to exfoliate to try and keep my skin tone even.

During the winter months, my skin is very dry, so I moisturize it with lotion every day. It still gets flaky, so I exfoliate with a loofah in the shower. I know that I remove more epithelial cells in a day than most people do in a week, so I’m glad they have such a high rate of regeneration.

Post 2

@cloudel - I have a kidney condition, too, and my urinary tract infection did spread into my kidneys. I waited too long, hoping the infection would disappear with my home remedy of drinking lots of cranberry juice and water.

After two weeks of urinary tract infection symptoms, I began vomiting and having pains in my lower back. Fearing damage to my kidneys, I made an appointment with my doctor.

She did a urinalysis and found kidney cells present. She gave me a strong antibiotic and told me never to put off treatment again. The infection could have severely damaged my kidneys, had I waited any longer.

Post 1

I had cloudy urine, frequent urination, a burning sensation, and cramps in the area of my bladder. These alone would have been enough for a diagnosis of a urinary tract infection, but because I also have a kidney disease, my doctor wanted to do a urinalysis to make sure the infection had not reached my kidneys.

While examining my urine sample, the doctor found lots of transitional epithelial cells. This told her that the infection was in my bladder. Had the infection been in my kidneys, she would have seen kidney cells in my urine.

She gave me an antibiotic to cure the infection. I had to get treatment, or the infection would likely spread to my kidneys.

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