Cytology Lecture Notes PDF

CYTOLOGY PROF. Eman Abas BADYA UNIV 1 BADYA UNIV 2  ILOS 1. Describe EM structure of ribosomes, centriole, cilia, flagella, microvilli 2. Enumerate &describe types &functions of ribosomes 3. Enumerate special stains for cytoskeleton,centriole 4. Enumerat...

CYTOLOGY PROF. Eman Abas BADYA UNIV 1 BADYA UNIV 2  ILOS 1. Describe EM structure of ribosomes, centriole, cilia, flagella, microvilli 2. Enumerate &describe types &functions of ribosomes 3. Enumerate special stains for cytoskeleton,centriole 4. Enumerate functions of centriole, cilia, flagella, microvilli 5. Compare between microvilli &cilia 6. Enumerate sites and function for Microfilaments 7. Enumerate sites and function for intermediate filaments BADYA UNIV  RIBO SOMES 11 BADYA UNIV Def: ptn Non mem electron dense bodies formed of rRNA & proteins. L s Origin r RNA (NUCLEOLUS) ptn +ptn (cytop) Join in nucleolus to form Small & large Subunits pass to cytoplasm again through nuclear pores join only during protein synthesis. 12 BADYA UNIV NO +++protein forming cells e.g. plasma cells LM when Abundant …cytoplasmic basophilia: Diffuse Focal Localized embryonic cell Nissl's gr.[nerve] BADYA UNIV pancreas 15  Nissl's granules in nerve cells 16 BADYA UNIV  EM Small electron dense gr. 2 sub units Small& large Attached by m RNA m RNA Large subunit contains groove for polypeptide chain present in 2 forms: 18 BADYA UNIV PP chain  Forms of ribosomes by EM 1- Attached 2-Free To rER Large Subunit Single Polysomes Ribophorins Pore Scattered linked by mRNA pp Spiral Rosette 20 BADYA UNIV  Function Factories of Ptn synthesis Attached Free Ptn secreted by cells: Ptn used inside cells: Hr, enz. Glycolytic enzymes 24 BADYA UNIV  Non-membranous organelles Ribosomes Cytoskeleton BADYA UNIV 26 Cytoskeleton Definition MTs+ Filaments (Micro&IM) + ptns Link them to each other& to CM forming frame= Micro trabecular lattice 27 BADYA UNIV  Microtubules = MTs Definition Hollow cylinder fixed diameter =24nm & unfixed length 24nm 29 BADYA UNIV  Structure 13 PR directed by microtubular organizing center which 30 (MTOC) contains gamma tubulin. BADYA UNIV 1 MT  LM Seen ONLY BY IMF 33 BADYA UNIV  Functions 1- determie cell shape 1- Determine cell shape 2- mitotic spindle =cell division 3- intracellular 2- Mitotic spindle transport of =cell division molecules 34 4- ccf BADYA UNIV  MI Cancer chemotherapy stop tumor cells proliferation by MTs and mitotic spindle formation 35 BADYA UNIV  Functions 1- 1- determie Determiecell cell shape shape 2- 2- mitotic Mitotic spindle spindle =cell =cell division division 3-3-intracellular Intracellular transport of transport of molecules organelles, vesicles 4- ccf 40 4- ccf BADYA UNIV  structures formed by MT 1- CENTRIOLES 2-CILLIA 3-FLAGELLA 42 BADYA UNIV  1- Centrioles DEF cylindrical str. formed of MTs LM Iron HX: 2 dark bodies near N 43 BADYA UNIV  EM 2 hollow cylinders at right angles to each other surrounded with tubulin = centrosome LS TS 45 BADYA UNIV  Each cylinder is formed of 27 microtubules Arranged as 9 bundles, Each bundle is formed of 3 MTs (triplets) [9 x 3 =27 MTs]. Each triplets is named as A,B&C from inner to outer 48 BADYA UNIV Functions of centriole 1. Cell division : Duplication Migrate to one pole MTs Mitotic spindle 2. Formation of CF 49 BADYA UNIV  2-Cilia Def: Motile- hair like processes –with MTs core & covered by CM LM: acidophilic hair like striations 50 BADYA UNIV  Origin Centriole duplication+++++ BBs migrate to apical cytop Grow shafts of cillia BB BB Centriole 51 BADYA UNIV EM: 3 parts Shaft= Finger like projection covered w CM 2 = 9 doublets+ 2 new singlets = 18+2 =20 MTs BB=cent=27MTs= 9 tripets Embedded in cytopl. 1 3 Rootlets=9 MT C inside 52 cytop fix BADYA UNIV C  Functions 1-Move particles & fluid in one direction in Resp &female genital sys: 2-Modify: receptors in rods&cones of retina 56 BADYA UNIV  T.S. in shaft of cilia 57 BADYA UNIV  3-Flagella Motile projections from the cell, to move the cell itself. = axoneme= 20Mts but longer FN: Form Tail of sperm for (movement ) 60 BADYA UNIV  MI Immotile FLAGELLA : Inability of cilia to move : male infertility Chronic resp tract infection 61 BADYA UNIV  Cytoskeleton definition MTs+ Filaments (M&IM) + ptns Link them to each other& to CM Micro trabecular lattice 2-Filaments ptns 65 BADYA UNIV  2Types ( size) sh 1-Micro fil.= 2-Intermediate fil. thin= actin 5-7 nm 6 8-10 nm 10 67 BADYA UNIV  1-Micro filament=thin= actin Structure Fine strands 5-7 nm 2 chains G actin (globular) coiled F actin (filamentous) Dynamic 69 BADYA UNIV  Sites& functions 1. under CM: Change cell Shape: endo- exo- ameboid mov 2. Intracellular transport of Vesicles, organelles 70 BADYA UNIV  3- Skeletal ms interact with myosin muscle contraction 73 BADYA UNIV 4- Dividing cells: interact with myosin separation of dividing cells 74 BADYA UNIV  5-form core of microvilli & stereocilia 75 BADYA UNIV  Finger like projections (shorter than cilia) from cell Microvilli?? membrane of some cells. L.M.: Apical striated brush border. E.M.: A core of actin filaments (to maintain its shape) coverd by cell memb. Function: Increase surface area for more absorption e.g.76small intestine BADYA UNIV  Microvilli 77 BADYA UNIV Stereocilia?? Non motile solid cilia Not true cilia but long microvilli L.M. hair like processes from free surface of some cells. E.M. core of actin filaments (no microtubules). Function: help absorption in male genital system e.g. epididymis. 78 BADYA UNIV  2-Intermediate filaments Structure 8-10 nm= intermediate in size Formed of, rod shaped between the microtubules subunits. &microfilaments FUNCTION 79 Supportive?? BADYA UNIV  LM Seen ONLY BY IMF 82 BADYA UNIV  Sites & types Epithelial cells Nuclear envelop neurons Glial cells Cytokeratin Lamins Neurofilament GFAP desmin CT & MS MS 83 Vimentin BADYA UNIV Desmin  MI Origin??? The cell origin of tumor can be recognized by Identification of intermediate filaments This is important in diagnosis & treatment of tumors. 86 BADYA UNIV Cytology 88  Thank you PROF. Eman Abas BADYA UNIV