Epithelial Tissues
Epithelial tissues are split into two types; simple and stratified. Simple tissues are one cell thick, whereas stratified tissues are multi-layered .
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Squamous
Simple squamous cells are the thin and flat this therefore they have a large surface area. that is exposed to the lumen on one side (the apical surface), and to the basement membrane (i.e. basal lamina) on the other. Squamous cells are bound together by tight junctions, making a selective barrier, which is crucial to its function.
Their function is to decide which substances are allowed to move through them. Their simple and thin construct allows easy transmembrane movement (across the membrane, and through the cell) of small molecules. Molecules such as oxygen and carbon dioxide can diffuse freely across the simple squamous cell according to their concentration gradients. Other molecules, like ions, use protein channels to diffuse across cells. The simple squamous epithelial helps to determine what is allowed to move from the lumen and into the bloodsteam and vice versa.
The simple squamous epithelium is found in place where rapid diffusion or filtration take place. For example, the kidneys.
Simple squamous cells are the thin and flat this therefore they have a large surface area. that is exposed to the lumen on one side (the apical surface), and to the basement membrane (i.e. basal lamina) on the other. Squamous cells are bound together by tight junctions, making a selective barrier, which is crucial to its function.
Their function is to decide which substances are allowed to move through them. Their simple and thin construct allows easy transmembrane movement (across the membrane, and through the cell) of small molecules. Molecules such as oxygen and carbon dioxide can diffuse freely across the simple squamous cell according to their concentration gradients. Other molecules, like ions, use protein channels to diffuse across cells. The simple squamous epithelial helps to determine what is allowed to move from the lumen and into the bloodsteam and vice versa.
The simple squamous epithelium is found in place where rapid diffusion or filtration take place. For example, the kidneys.
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Cuboidal
Cuboidal cells have a cuboid shape with a central nucleus. Some cuboidal cells may have microvilli on their surface depending on their location. These cells have selective permeability.
Cuboidal cells are good at helping with absorption. These cells are used as a lining to protect from abrasion, foreign particles, bacteria and water loss (due to its selective permeability) to the underlying tissue. In the kidney , the cells help in the absorption and transport of filtered substances.
Simple cuboidal epithelium lines the surface of small excretory ducts in organs and glands in the body. They also make up some of the kidney tubules in the kortex of the kidney, and create the covering of the ovary.
Cuboidal cells have a cuboid shape with a central nucleus. Some cuboidal cells may have microvilli on their surface depending on their location. These cells have selective permeability.
Cuboidal cells are good at helping with absorption. These cells are used as a lining to protect from abrasion, foreign particles, bacteria and water loss (due to its selective permeability) to the underlying tissue. In the kidney , the cells help in the absorption and transport of filtered substances.
Simple cuboidal epithelium lines the surface of small excretory ducts in organs and glands in the body. They also make up some of the kidney tubules in the kortex of the kidney, and create the covering of the ovary.
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Columnar
Simple columnar epithelial cells are longer than wide. Usually their nuclei are found at the bottom of the cell. The cells are connected by tight junctions. The cells receive nutrients through the basement membrane, which separates the cells from the capillary basal layer.
The function of simple columnar epithelial cells is protection.The epithelium in the stomach and digestive system makes an impermeable barrier against any bacteria, but it is also permeable to any necessary ions. This function is especially important in the colon. Simple columnar epithelial cells can be specialized to secret mucus that coats and protects the surrounding surface from damage. These cells are good at absorbing things and transporting nutrients These cells are found in the cornea, ear, and nose.
Pseudostratified Columnar
The name of this cells actually refers to the structure, although they look like they're the stratified version of the simple columnar however 'pseudo'
actually means false showing that this cell is one cells thick too. They appeared stratified as they are tightly packed together. This also means that their nuclei are forces to opposite ends of the cells. Seen as the.
Ciliated pseudostratified columnar cells are found in the trachea , they help to sweep foreign body's out of your throat.
Pseudostratified columnar epithelia cells are found forming the straight, tubular glands of the endometrium in females.
Simple columnar epithelial cells are longer than wide. Usually their nuclei are found at the bottom of the cell. The cells are connected by tight junctions. The cells receive nutrients through the basement membrane, which separates the cells from the capillary basal layer.
The function of simple columnar epithelial cells is protection.The epithelium in the stomach and digestive system makes an impermeable barrier against any bacteria, but it is also permeable to any necessary ions. This function is especially important in the colon. Simple columnar epithelial cells can be specialized to secret mucus that coats and protects the surrounding surface from damage. These cells are good at absorbing things and transporting nutrients These cells are found in the cornea, ear, and nose.
Pseudostratified Columnar
The name of this cells actually refers to the structure, although they look like they're the stratified version of the simple columnar however 'pseudo'
actually means false showing that this cell is one cells thick too. They appeared stratified as they are tightly packed together. This also means that their nuclei are forces to opposite ends of the cells. Seen as the.
Ciliated pseudostratified columnar cells are found in the trachea , they help to sweep foreign body's out of your throat.
Pseudostratified columnar epithelia cells are found forming the straight, tubular glands of the endometrium in females.
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Keratinized Stratified Squamous
Keratinized stratified squamous epithelium has multiple layers of dead cells at the surface.
Keratin is a substance produced within maturing cells, it is used to waterproof the cells and block diffusion of nutrients and waste.
Keratinized stratified squamous epithelium is found only in the skin. It helps our skin protect us as the multi-layers help to prevent easy scarring and unnecessary blood loss from small cuts.
Keratinized stratified squamous epithelium has multiple layers of dead cells at the surface.
Keratin is a substance produced within maturing cells, it is used to waterproof the cells and block diffusion of nutrients and waste.
Keratinized stratified squamous epithelium is found only in the skin. It helps our skin protect us as the multi-layers help to prevent easy scarring and unnecessary blood loss from small cuts.
![Picture](/uploads/6/2/8/5/62859715/772165.gif?250)
Transitional Stratified
Transitional tissues are made up of 3 types of cells; Basal, intermediate, and superficial. The basal layers provides a constant renewal of epithelium, therefore they have many mitochondria. the intermediate cell layer provides rapid cell regeneration, they contain many Golgi apparatus and membrane-bound vesicles to help transport proteins rapidly (Such as keratin). The superficial layer provides protection to the bloodstream as it forms a barrier so no pathogens can get through.
The transitional tissues has the ability stretch. This is very useful in the urinary tract as fluid pressures vary. It is found as a lining of the ureters, urethra, and bladder.
Transitional tissues are made up of 3 types of cells; Basal, intermediate, and superficial. The basal layers provides a constant renewal of epithelium, therefore they have many mitochondria. the intermediate cell layer provides rapid cell regeneration, they contain many Golgi apparatus and membrane-bound vesicles to help transport proteins rapidly (Such as keratin). The superficial layer provides protection to the bloodstream as it forms a barrier so no pathogens can get through.
The transitional tissues has the ability stretch. This is very useful in the urinary tract as fluid pressures vary. It is found as a lining of the ureters, urethra, and bladder.
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