• Avascular – having no blood supply. • Made up of numerous cells packed tightly together, surrounded by little or no extracellular substance. • Cells held together by tight junctions and desmosomes. • Highly regenerative • Connected to underlying connective tissue by the basement membrane. • Gains nutrients from CT which diffuse through basement membrane.
Classification
ET can be classified firstly by the number of cell layers.
• 1 single layer of cells is termed simple epithelium. • More than 1 layer of cells is referred to as stratified epithelium.
ET can be further classified by the shape of the cells that make up the epithelial tissue.
• Squamous • Cuboidal • Columnar
Location
• Covers external and internal body surfaces • Located in areas of wear and tear – e.g. outer layer of skin, oral mucosa.
Just thought I would start with the first few dot points and hopefully someone else can continue!
The basement membrane is formed when the upper basal layer of epithelial cells form a basal lamina. This joins/attaches/fuses to the reticular lamina of the underlying connective tissue to form the basement membrane.
The role of the basement membrane: - Its primary function is to anchor the epithelial cells to the underlying connective tissue - Act a protective barrier against malignant cells (such as cancer cells) and against foreign objects. This is important in areas such as the stomach, skin and the mouth because it stops unwanted objects from entering the body and reaching underlying tissues. - It can help with angiogenesis, or the production of new blood vessels.
some functions of ET: - protects underlying tissue -allows materials to pass through via diffusion and filtration -secretes substances(glands serecte lubricating substances such as mucus)
Good work guys. However, you cant really refer to the basal layers as "upper". I know you meant upper in relation to the reticular lamina, however basal layers are always the deeper layers. "Upper" gives the impression that they are on top. Keep the great work going.
Elise, there is one more function that you missed. Can anyone think of it?
Sophie, i think that the other funtion of ET is that it has the ability to rapidly repair itself - due to a high turnerover rate of cell regeneration. Which is why it is best suited to areas such as the oral cavity where friction and mastication occure.
Hi Denny yes your statement is correct, but that is not the one I was looking for. Its more along the lines of it forms ............and ............... that secrete .............., ............... and ........... respectively. Anyone want to have a go?
Another function of ET i think is that they can provide sensation, most of epithelia are extremely sensitive to stimulation because they have a large sensory nerve supply.
Hi Sophie, what's in mind now is that along the lines of it forms edocrine glands and exocrine glands that secrete hormones and many forms of exocrine secretions such as enzymes, perpiration etc. it does not match the blanks exactly though, hopefully my answer wasnt far away from the correct one?!
Characteristics of ET
ReplyDelete• Avascular – having no blood supply.
• Made up of numerous cells packed tightly together, surrounded by little or no extracellular substance.
• Cells held together by tight junctions and desmosomes.
• Highly regenerative
• Connected to underlying connective tissue by the basement membrane.
• Gains nutrients from CT which diffuse through basement membrane.
Classification
ET can be classified firstly by the number of cell layers.
• 1 single layer of cells is termed simple epithelium.
• More than 1 layer of cells is referred to as stratified epithelium.
ET can be further classified by the shape of the cells that make up the epithelial tissue.
• Squamous
• Cuboidal
• Columnar
Location
• Covers external and internal body surfaces
• Located in areas of wear and tear – e.g. outer layer of skin, oral mucosa.
Just thought I would start with the first few dot points and hopefully someone else can continue!
Well done Sophie!!
ReplyDeleteCan some one talk a little more about the basement membrane and how it is formed. What is its role?
The basement membrane is formed when the upper basal layer of epithelial cells form a basal lamina. This joins/attaches/fuses to the reticular lamina of the underlying connective tissue to form the basement membrane.
ReplyDeleteThe role of the basement membrane:
- Its primary function is to anchor the epithelial cells to the underlying connective tissue
- Act a protective barrier against malignant cells (such as cancer cells) and against foreign objects. This is important in areas such as the stomach, skin and the mouth because it stops unwanted objects from entering the body and reaching underlying tissues.
- It can help with angiogenesis, or the production of new blood vessels.
some functions of ET:
ReplyDelete- protects underlying tissue
-allows materials to pass through via diffusion and filtration
-secretes substances(glands serecte lubricating substances such as mucus)
Good work guys. However, you cant really refer to the basal layers as "upper". I know you meant upper in relation to the reticular lamina, however basal layers are always the deeper layers. "Upper" gives the impression that they are on top.
ReplyDeleteKeep the great work going.
Elise, there is one more function that you missed. Can anyone think of it?
Sophie
Sophie, i think that the other funtion of ET is that it has the ability to rapidly repair itself - due to a high turnerover rate of cell regeneration. Which is why it is best suited to areas such as the oral cavity where friction and mastication occure.
ReplyDeleteplease correct me if I am wrong though!
Hi Denny
ReplyDeleteyes your statement is correct, but that is not the one I was looking for. Its more along the lines of it forms ............and ............... that secrete .............., ............... and ........... respectively. Anyone want to have a go?
Another function of ET i think is that they can provide sensation, most of epithelia are extremely sensitive to stimulation because they have a large sensory nerve supply.
ReplyDeleteTracy.. great one. Now that's applying your knowledge!! Can you guess the missing word in my post?
ReplyDeleteHi Sophie,
ReplyDeletewhat's in mind now is that along the lines of it forms edocrine glands and exocrine glands that secrete hormones and many forms of exocrine secretions such as enzymes, perpiration etc. it does not match the blanks exactly though, hopefully my answer wasnt far away from the correct one?!
Your spot on Tracy.
ReplyDeleteWell done.