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PDMC NEB test marks distribution

1. Applied Anatomy (Total Mark's 20)

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  Histology   Embryology   Neuroanatomy   Gross anatomy =================================                  HISTOLOGY CELL: The  cell  is the basic structural and functional unit of all living organisms. Cells vary widely in size and shape depending on their function. Microscopes are used to study cells because most cannot be seen with an unaided eye. TISSUE: 1.Epithelium Tissue:                                 Classification                                                       1. Simple Epithelium                                         Simple squamous epi   Simple cuboidal    epi   Simple columnar  epi                     2. Stratified Epithelium   Stratified squamous epi                                           I. Keratinized.                                                       II. Non Keratinized    Stratified cuboidal    epi         Stratified columnar  epi              3.Pseudostratified Epithelium     Cilliated columnar epi   Non-cilli
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CARTILAGE

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        CARTILAGE      The cartilage is a special type of connective tissue which is characterized by its resilient and pliant nature. It is found at those places in the body where structural support with flexibility is required.
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CONNECTIVE TISSUE

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LOSS CONNECTIVE TISSUE : 1.ADIPOSE :                        Adipose characterized by presence of considerable amount of fat in cytoplasm and so called FAT CELLS
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TRANSITIONAL EPITHELIUM

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More than one cell layers  Number of cells layers change able depend on orgen  The structure of the transitional epithelium is best studied in sections of the wall of the urinary bladder. It is to be noted that the microscopic structure of this special type of multilaminar epithelium varies greatly according to the state of distension of the urinary bladder. Undistended (contracted) Transitional epi: Transtional (contracted)    In the undistended (i.e, contracted) urinary bladder, the urothelium appears to consist of 6 or more layers of cells. The basal layer of the epithelium consists of cuboidal cells. Over the basal layer are present several layers of polygonal cells. The most superficial layer of the epithelium appears to consist of very large dome-shaped cells also called umbrella cells whose highly convex apices bulge into the bladder cavity. Some of the umbrella cells contain two nuclei. Distension (stretched) Transtional epi: Transtional (distended)  Dis
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PSEUDOSTRATIFIED COLUMNAR EPITHELIUM

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      This type of epithelium consists of tall cells and short cells. All cells of the pesudostratified columnar epithelium rest on the basement membrane but all of them do not reach the free surface of the epithelium. Only the tall columnar cells extend through the entire thickness of the epithelium. Each of these cells has a wider part which reaches the free surface of the epithelium and a narrow and slender basal part which passes downward to rest on the basement membrane. The short cells also called basal cells, lie between the columnar cells. The basal cells are conical in shape having a broad base which rests on the basal lamina and a tapering upper part which terminates between the columnar cells and does not reach the free surface of the epithelium. As the cell nuclei are located in the wider parts of both types of the cells of the pseudostratified columnar epithelium they are present in the apical part of the tall cells and basal parts of the short cells. The nuclei of all th
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STRATIFIED COLUMNAR EPITHELIUM

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This variety of stratified epithelium consists of columnar surface cells which rest on one or more layers of roughly cuboidal cells. This epithelium also has a restricted distribution in the body. The lining epithelium of the conjunctiva of the eye is a typical example of the stratified columnar epithelium. Some parts of the male urethra are also lined by the stratified columnar epithelium. Unlike the stratified squamous epithelium the surface cells of the stratified cuboidal and stratified columnar epithelia are not continuously replaced by basal mitosis and there is no progress from the base to surface. Stratified Columnar Epithelium  
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STRATIFIED CUBOIDAL EPITHELIUM

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The stratified cuboidal epithelium consists of two or three layers of cuboidal cells. This type of epithelium has a very restricted distribution in the human body. It only occurs as the lining of the larger ducts of some exocrine glands like pancreas and salivary glands. The ducts of the sweat glands are also lined by this type epithelium. The stratified cuboidal epithelium has not been found to be involved in absorptive or secretory activity. Its probable function is to provide the ducts with a stronger lining than the simple cuboidal or simple columnar epithelium. Stratified Cuboidal Epithelium Found In: Follicular Antrum Ducts of sweat glands
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STRATIFIED SQUAMOUS EPITHELIUM

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The number of layers in this type of epithelium varies considerably in different locations but the shape and arrangement of the cells are quite characteristic. The deepest or basal layer which rests on a basement membrane is formed by low columnar or cuboidal cells which steadily divide mitotically to provide a constant supply of cells for the overlying layers. Next to the basal layer are present a few layers of larger polygonal cells. Stratified Squamous Epithelium   As the free surface is approached the cells gradually become flattened and at the surface they assume a squamous 'flat' shape. The condition of the cells of the most superficial layers of the stratified squamous epithelium varies with the location and environment of the epithelium. Two subvarieties of the stratified squamous epithelium are recognized:     Kratinized (also called cornified)                      Nonkeratinized (also called noncornified) KRATINIZED The stratified squamous keratinize
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STRATIFIED EPITHELIA

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These epithelia consist of two or more layers of cells. In which only the bottom layer rests on the basement membrane. Stratified epithelia are further classified into subtypes according to the shape of the cells in the superficial layer. The layer on the free surface of the epithelium. Stratified Epithelia This group of epithelia has the following types. stratified squamous epithelium stratified cuboidal epithelium stratified columnar epithelium A special type of the stratified epithelia is called transitional epithelium.
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SIMPLE COLUMNAR EPITHELIUM

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Simple Columnar Epithelium This type of epithelium consists of a single layer of columnar (column-shaped cells). On surface view the cells appear as a mosaic resembling that of simple cuboidal epithelium but the outline of the cells is rather smaller. In pendicular sections the columnar shape of the cells becomes evident in which it is seen that the height of each cell is much greater than its width. The nucleus is commonly oval in shape and usually located near the base of the cell. The nuclei of all the cells of a sheet of simple columnar epithelium are often seen to be situated at roughly at the same level. Simple columnar epithelium is widely distributed in the body. Simple Columnar Epithelium   It lines (for example) :  the internal surface of  Stomach  Intestines  Gallbladder  Uterus  In many locations in the body  The cells of the simple columnar epithelium show modifications on their apical surface, which includes microvilli, kinocilia and stereocilia.
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SIMPLE CUBOIDAL EPITHELIUM

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Simple Cuboidal Epithelium                   This variety of epithelium also consists of a single layer of closely-packed cells. In sections made perpendicular to the epithelial sheet. The cells give a roughly square outline, the height and width of each cell appearing to be nearly equal. This appearance is the reason why this variety of epithelium was titled in earlier times as cuboidal epithelium. The surface view of the epithelium reveals that the cells are rather hexagonal or polygonal in shape. The closely fitting cells appearing to form a mosaic. Each cell contains a spherical nucleus which is located in the center of the cell. The simple cuboidal epithelium has a restricted distribution in the body. Simple Cuboidal Epithelium  Examples  (i) The epithelium lining the follicles of the thyroid Gland.  (ii) The epithelium lining the distal convoluted tubules of the kidneys. Found In :  Glands Tubles and Acini of most of glands. 
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