Cytology - Benha University Past Notes PDF

Benha University Faculty of Veterinary Medicine Histology Department Cytology Prof. Dr: Ehab Mahmoud Abdelaal Elzoghby Prof. of Histology and Head of Dept. ›It is one of the biological sciences which study the structure, histochemistry and ultr...

Benha University Faculty of Veterinary Medicine Histology Department Cytology Prof. Dr: Ehab Mahmoud Abdelaal Elzoghby Prof. of Histology and Head of Dept. ›It is one of the biological sciences which study the structure, histochemistry and ultrastructure of the cell concerning the immunohistochemistry and cell genetics. Cell › A- Cytoplasm › B- Nucleus A-Cytoplasm 1-Organelles 2-Inclusion 3-Other component (a) Membranous Organelles:- 1) cell membrane 2) Mitochondria 3) Endoplasmic reticulum (a-rough and b-smooth) 4) lysosome 5) Golgi Apparatus (b) non membranous 1) Free ribosome. 2)Cilia & flagella 3) Microtubules. 4) Filament & fibrils. 5) centriole “centrosome” 2-Inclusion Secretory granules Stored food Pigments a- Lipid 1) Exogenous b- Carbohydrate 2) Endogenous B-Nucleus 1-Cell membrane:- 1-It also known as plasmalemma & plasma membrane (trilaminar structure) 2- is composed of dense layer of cytoplasm surround cell. 3- is composed of 2 layer of dense protein in between present phospholipids 4- Its thickness range from 8:10 nm only can seen with E.M & appear as protein swim in a sea lipid Types of Microscope : 1- Light Microscope 2- Electron Microscope it appears as trilaminar structure , outer and inner dark layer and middle light layer , this configuration due to→ it appear like that due to deposition of reduced osmium stain on the hydrophilic side of the cell membrane These are some “theories of the structure of cell membrane Linear theory Molecular theory Fluid mosaic theory 1-Linear Theory, as the cell membrane appear as 3 line, 2 dense bilayer Phospholipids→ hydrophilic and one light intermediate→ hydrophobic 2-Fluid Mosaic theory, globules of protein move freely through the cell membrane. They are floating & changing their position from time to time. Protein → extrinsic” peripheral” are present in one side of the lipid bilayer “outside” & closely bounded to the cytoplasmic side “has non polar bond” 3) Molecular theory: it indicates biochemical structure of the cell membrane. Phospholipids” hydrophilic head, hydrophobic tail. Protein “integral and peripheral” Carbohydrate “glycoprotein and glycolipid. Cholesterol has fixing rule that it make phospholipids backed tightly together. Function: 1-Protective 2-Regulate transport in and out of cell or subcellular domain. 3-Allow cell recognition 4- Provide a stable site for the binding and catalysis of enzymes. 5- Regulate the fusion of the membrane with other membranes in the cell via specialized junctions) 6- provide a passageway across the membrane for certain molecules, such as in gap junctions. 7- Allow directed cell or organelle motility 2- MITOCHONDRIA:- 1-Mitochondria" is a plural term; which is appropriate because it is not usual to find a single "mitochondrion. 2-Mitochondria provide the energy a cell needs to move, divide 3-They are the power centers of the cell. 4-They have different shapes depending on the cell type. 5-One 5- of the cytoplasmic organelles, membranous can seen with light microscope using” supra vital dye of Janus “green color” 6-It bounded by 2 membrane separated with inter membranous space. 7-It may be short rods, threads or granules. About 2500- 3000 in each cell & increase in cell with high metabolic action. E.M. Bounded with 2 membranes. “Outer is smooth, inner extended in ward forming crista or internal ridge which divided mitochondria into incomplete compartments. The inner membrane has mitochondrial granules or elementary particles which consist of head, neck and base. It also contains matrix granules Thank You  Benha University Faculty of Veterinary Medicine Histology Department Cytology Prof. Dr: Ehab Mahmoud Abdelaal Elzoghby Prof. of Histology and Head of Dept. 1-Linear Theory, as the cell membrane appear as 3 line, 2 dense bilayer Phospholipids→ hydrophilic and one light intermediate→ hydrophobic 2-Fluid Mosaic theory, globules of protein move freely through the cell membrane. They are floating & changing their position from time to time. Protein → extrinsic” peripheral” are present in one side of the lipid bilayer “outside” & closely bounded to the cytoplasmic side “has non polar bond” 3) Molecular theory: it indicates biochemical structure of the cell membrane. Phospholipids” hydrophilic head, hydrophobic tail. Protein “integral and peripheral” Carbohydrate “glycoprotein and glycolipid. Cholesterol has fixing rule that it make phospholipids backed tightly together. Function: 1-Protective 2-Regulate transport in and out of cell or subcellular domain. 3-Allow cell recognition 4- Provide a stable site for the binding and catalysis of enzymes. 5- Regulate the fusion of the membrane with other membranes in the cell via specialized junctions) 6- provide a passageway across the membrane for certain molecules, such as in gap junctions. 7- Allow directed cell or organelle motility 2- MITOCHONDRIA:- 1-Mitochondria" is a plural term; which is appropriate because it is not usual to find a single "mitochondrion. 2-Mitochondria provide the energy a cell needs to move, divide 3-They are the power centers of the cell. 4-They have different shapes depending on the cell type. 5-One of the cytoplasmic organelles, membranous can seen with light microscope using” supra vital dye of Janus “green color” 6-It bounded by 2 membrane separated with inter membranous space. 7-It may be short rods, threads or granules. About 2500- 3000 in each cell & increase in cell with high metabolic action. E.M. Bounded with 2 membranes. “Outer is smooth, inner extended in ward forming crista or internal ridge which divided mitochondria into incomplete compartments. The inner membrane has mitochondrial granules or elementary particles which consist of head, neck and base. It also contains matrix granules 3-LYSOSOMES  ›How lysosome are formed. Types ›Membranous organelles contain ›The lysosome are the freshly formed hydrolytic enzyme (acidic). secretory vesicle contain hydrolytic ›Lysosomes are tiny sacs filled with enzyme “primary lysosome” ›It comes from r.E.R as transfer vesicle enzymes contains enzyme synthesis with ribosome of r.E.R. ›800 nm in diameter. ›When they grow up in the saccules of the Golgi they bud off from the mature face ›It derived from Golgi complex. of the Golgi as secretory vesicle. ›L.M → vesicle of basophil, ›Secondary lysosome, when the primary lysosome phagocytosis any undesirable eosinophil and/ neutrophil. vesicle in the cytoplasm then called secondary lysosome. ›E.M → homogenous round vesicle ›If fuse with phagocytic vesicle” “phagosome” when enzyme digest vesicle bounded with thin membrane. → result residual body. ›If fuse with torn, old cytoplasmic content “cytolysosome or autophagic vacuole”. › Release enzymes outside of the cell (exocytosis) › Break-down 'digestion' of materials from inside the cell (autophagy) phagocytic - by which cells engulf extracellular debris, bacteria or other particles - only occurs in certain specialized cells pinocytic - by which cells engulf extracellular fluid endocytic - by which cells take-up particles such as molecules that have become attached to the outer-surface of the cell membrane. Recycle the products of biochemical reactions that have taken place following materials being brought into the cell by endocytosis (general term for this 'recycling' function: biosynthesis) › Completely break-down cells that have died (autolysis) 4- R.E.R ›Membranous organelles, which is the ›L.M site of manufacture of proteins. ›Appear as basophilic substance.. ›ribosomes attached to the surfaces of ›NB (rER+ ribosome) in Nerve cell the endoplasmic reticulum. called Nissl’s body. ›Three dimension network of ›E.M. branching & anastomosing membrane. ›Parrelled stack of flatten cisternae. ›Bounded and flatten tubules. ›It continues with nuclear envelope. ›Widen sacs like structure “Cisternae” ›Ribosome gives granular within the meshes of the cisternae appearance. › Ribosome present on the surface of ›Function :- the sacs gives rough appearance. 1) Synthesis of intracellular protein  Click icon to add picture 5- SER  Membranous network devoid of ribosome  It is more tubular interconnected and communicate with r.E.R ›Function →  Biosynthesis of phospholipids & fatty acid.  Resynthsis of absorbed lipid and transport it to absorptive intestinal cell.  SMOOTH ENDOPLASMIC ROUGH ENDOPLASMIC BASIS FOR COMPARISON RETICULUM RETICULUM Meaning Smooth ER appears like Rough ER looks like the containing many circular arrangement of the marks which are the double membranes interlocking tubular which are spotted with sheets and they may be the ribosomes all over. varied in look and They appear consisting function as well. of the parallel sheets of membrane. Found near Smooth ER is found near Rough ER is found near the cell membrane. the cytoplasm and attached with the nucleus. Originates from Rough endoplasmic From nuclear membrane. reticulum by giving off the ribosomes. Ribosomes They do not have They have ribosomes. ribosomes.  (Microsome) It denotes as vesicle generated from fragmentation of ER ‫يشير إلى الحويصلة‬ ‫الناتجة عن تجزئة‬ during process of ER ‫أثناء عملية‬ homogenization that preceded ‫التجانس التي‬ differential or “density ‫سبقت التفاضل أو‬ gradient centrifugation” so it ‫"الطرد المركزي‬ should never applied to intact "‫المتدرج الكثافة‬ cell. ‫لذلك ال ينبغي أبدًا‬ 6-GOLGI APPARATUS ›Golgi network, Golgi apparatus ›It is called "Post Office" of the cell. The ›Membranous organelles consist ›* The shape of the Golgi apparatus of several number of flatten sacs varies according to physiological state. (saccules) or cisternae that stack › Hungary→ small dense body in intestinal cell. together like plate of cups. › Feeding→ increase in size. › The Golgi apparatus consists of a collection of vesicles and › Young→ Golgi form small net like folded membranes. These are structure in the axon pole of the nerve usually connected to an endoplasmic reticulum (ER) as cell. the Golgi › Aging → theses small net became fragmented or discrete granules. E.M. ›Parallel array of smooth surface membrane called flatten saccules or cisternae. ›These cisternae flatten peripherally “budding” to give Ribosomes ›It has two surface:  Concave ( mature or trans ), it associated with secretory vesicles of various stage of condensation & maturation  Convex (immature), it associated with transferred vesicle of r.E.R.  GERL › It is area near the Golgi › Function present in certain type of cells › may be second sort of secretory product › appearance 1→ flat “modification” of fenestrated saccules protein from r.E.R with dilatation › 2→ › contain phosphates anastomosing enzyme share in connecting tubules lysosome production › the cisternae of r.E.R › Part of Golgi has the “area cisternae free same role. ribosome” may has connection with it Thank You