تويت
Epithelium Images
السلام عليكم ورحمة الله وبركاتة.
إستجابة لطلاب الأخوه والأخوات بطلب صور علم الأنسجة (HISTOLOGY) , هذي صور من بحثي بالانترنت , و إن شاء الله تفيد ,,
Epithelium
SIMPLE SQUAMOUS EPITHELIUM:
Uterine tube.
Simple squamous epithelium can be studied by looking at cells which line blood and lymph vessels. These flattened cells are called endothelial cells . The nuclei are frequently found protruding into the lumen of the vessel. Observe the numerous large blood vessels present in the periphery of this section. Simple squamous epithelium is also the outer covering of the uterine tube which is termed the mesothelium .
SIMPLE SQUAMOUS EPITHELIUM:
Uterine tube.
Simple squamous epithelium can be studied by looking at cells which line blood and lymph vessels. These flattened cells are called endothelial cells . The nuclei are frequently found protruding into the lumen of the vessel. Observe the numerous large blood vessels present in the periphery of this section. Simple squamous epithelium is also the outer covering of the uterine tube which is termed the mesothelium .
SIMPLE CUBOIDAL EPITHELIUM:
Kidney.
Simple cuboidal epithelium is prominent in the cortex and medulla of the kidney. Proximal convoluted tubules , distal convoluted tubules , and collecting ducts are examples of simple cuboidal epithelium.
Kidney.
Simple cuboidal epithelium is prominent in the cortex and medulla of the kidney. Proximal convoluted tubules , distal convoluted tubules , and collecting ducts are examples of simple cuboidal epithelium.
SIMPLE COLUMNAR EPITHELIUM:
Duodenum.
Locate a large fingerlike projection at the surface of the organ (this is an intestinal villus ). Observe that the projection has an internal component and a surface. The surface of each villus is covered with simple columnar epithelium . The free surface of these cells has very tiny projections called microvilli , which are specialized for absorption (absorptive cells). Numerous mucus-secreting cells, known as goblet cells because of their shape, are dispersed between the absorptive cells. In the lab or on Hippocrates, locate an electron micrograph of an intestinal absorptive cell and compare the details which you see in your light microscope with those seen on electron micrographs.
Duodenum.
Locate a large fingerlike projection at the surface of the organ (this is an intestinal villus ). Observe that the projection has an internal component and a surface. The surface of each villus is covered with simple columnar epithelium . The free surface of these cells has very tiny projections called microvilli , which are specialized for absorption (absorptive cells). Numerous mucus-secreting cells, known as goblet cells because of their shape, are dispersed between the absorptive cells. In the lab or on Hippocrates, locate an electron micrograph of an intestinal absorptive cell and compare the details which you see in your light microscope with those seen on electron micrographs.
PSEUDOSTRATIFIED CILIATED COLUMNAR EPITHELIUM:
Trachea.
Note the ciliated, pseudostratified columnar epithelium lining the tracheal lumen. This epithelium is commonly referred to as "respiratory epithelium". Compare cilia with the microvilli on Slide 52. Note that the cilia are much longer. Study the ultrastructure of cilia and microvilli in electron micrographs.
Trachea.
Note the ciliated, pseudostratified columnar epithelium lining the tracheal lumen. This epithelium is commonly referred to as "respiratory epithelium". Compare cilia with the microvilli on Slide 52. Note that the cilia are much longer. Study the ultrastructure of cilia and microvilli in electron micrographs.
Epididymis, efferent ducts.
Distinguish between the epididymis and the efferent ducts in this slide by the appearance of the lumen in each organ. The epididymis has a smooth, even epithelium lining its lumen; while the efferent ducts are more scalloped in appearance. Both are examples of pseudostratified columnar epithelium. Especially note the stereocilia (long microvilli) of the epididymis.
Distinguish between the epididymis and the efferent ducts in this slide by the appearance of the lumen in each organ. The epididymis has a smooth, even epithelium lining its lumen; while the efferent ducts are more scalloped in appearance. Both are examples of pseudostratified columnar epithelium. Especially note the stereocilia (long microvilli) of the epididymis.
STRATIFIED SQUAMOUS EPITHELIUM (KERATINIZING AND NONKERATINIZING):
Esophagus.
Stratified squamous nonkeratinizing epithelium lines the lumen of the esophagus. This type of epithelium is found in mucous membranes.
Esophagus.
Stratified squamous nonkeratinizing epithelium lines the lumen of the esophagus. This type of epithelium is found in mucous membranes.
Skin, sole of foot.
Slide 44 is another of example of stratified squamous keratinizing epithelium . It is typical of thin skin . Note the difference in the thickness of the stratum corneum , the outermost layer.
Slide 44 is another of example of stratified squamous keratinizing epithelium . It is typical of thin skin . Note the difference in the thickness of the stratum corneum , the outermost layer.
STRATIFIED CUBOIDAL AND STRATIFIED COLUMNAR EPITHELIUM:
Submaxillary Gland.
Stratified columnar epithelium is often found at the junction between simple columnar epithelium and stratified squamous epithelium. The ducts of the salivary glands fit into this category and are shown in this slide. Also observe some stratified cuboidal epithelium lining the larger ducts found in this section (typically lying within connective tissue septa).
Submaxillary Gland.
Stratified columnar epithelium is often found at the junction between simple columnar epithelium and stratified squamous epithelium. The ducts of the salivary glands fit into this category and are shown in this slide. Also observe some stratified cuboidal epithelium lining the larger ducts found in this section (typically lying within connective tissue septa).
Skin, sole of foot.
Stratified cuboidal epithelium is found in the ducts of sweat glands . Look for these sweat glands well beneath the surfacing epithelium.
Stratified cuboidal epithelium is found in the ducts of sweat glands . Look for these sweat glands well beneath the surfacing epithelium.
Skin, scalp.
Note the presence of characteristic surface dome cells in the transitional epithelium .
Note the presence of characteristic surface dome cells in the transitional epithelium .
TRANSITIONAL EPITHELIUM:
Ureter.
In this slide, the ureter is preserved in various degrees of distention for better observation of the features of transitional epithilium. Compare the distended epithelium to the relaxed epithelium .
Ureter.
In this slide, the ureter is preserved in various degrees of distention for better observation of the features of transitional epithilium. Compare the distended epithelium to the relaxed epithelium .
Urinary bladder.
Again, find the transitional epithelium that lines the urinary bladder.
Ureter.
In this slide, the ureter is preserved in various degrees of distention for better observation of the features of transitional epithilium. Compare the distended epithelium to the relaxed epithelium .
In this slide, the ureter is preserved in various degrees of distention for better observation of the features of transitional epithilium. Compare the distended epithelium to the relaxed epithelium .
BASEMENT MEMBRANE:
Trachea.
The basement membrane is clearly seen underlining the "respiratory epithelium". This is refractile and pink. Be able to identify the components of this structure at the ultrastructural level.
Trachea.
The basement membrane is clearly seen underlining the "respiratory epithelium". This is refractile and pink. Be able to identify the components of this structure at the ultrastructural level.
CELL JUNCTIONS & NUCLEI:
Skin, scalp.
The basophilic tissue covering one surface is the epidermis of the skin. The cells of this covering are fastened together with a multitude of desmosomes. Examine the epidermis and try to resolve the cell borders , which stain lighter. Using the oil immersion lens, critically examine the zone between the cells and observe what appears like spiny projections . At mid point of each spine is where each desmosome is located. Desmosomes can be observed in the electron micrographs. Think about the dimension of a desmosome and reflect on what you were able to see with your light microscope and in the electron micrographs.
Skin, scalp.
The basophilic tissue covering one surface is the epidermis of the skin. The cells of this covering are fastened together with a multitude of desmosomes. Examine the epidermis and try to resolve the cell borders , which stain lighter. Using the oil immersion lens, critically examine the zone between the cells and observe what appears like spiny projections . At mid point of each spine is where each desmosome is located. Desmosomes can be observed in the electron micrographs. Think about the dimension of a desmosome and reflect on what you were able to see with your light microscope and in the electron micrographs.
Skin of palm.
Note the increased detail than can be seen in the epidermis in this 1.5µm section.
Note the increased detail than can be seen in the epidermis in this 1.5µm section.
هذا كل شئ تقريباً عن Epithelium وإن شاء الله راح يكون الموضوع في تحديث دائم ومستمر , وبقية الأنسجة تأتي قريباً... 
ننتظر آرائكم وإقتراحاتكم , وأي أخطاء أخبرونا بها وجل من لا يسهو ...
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