Most important Flashcards
When and who made the first LM?
Janssen and Janssen 1590
Special microscopes
- Stero microscope
- Dark field microscope
- Phase contrast microscope
- Polarization microscope
- Flueroscence microscope
- Confocal scanning microscope
Process for preparation of tissue for LM
- Collection of samples
- Fixation
- Dehydration and wax solvent
- Embedding
- Cut slices
- Mount on slides
- Remove wax and rehydrate
- Staining
- Remove surplus staind and water - apply mounting medium and coverslip
The principle and preparation of tissue for immunocytechemistry
Principle: foreign proteins recognized as antigens->immune response->prod. of antibodies which binds the antigens. Imm.cyto.chem. recognized these antibodies for localization of tissue components.
Collection of samples: tissue blocks from exp.animals, biopsys, smears, etc.
Fixation: immersion or perfusion
Principle for EM + the types of EM
Electron behave as light in vacuum.
- TEM - Transmission EM
- SEM - Scanning EM
Preparation of tissue for EM
- Fixation (immersion or perfusion)
- Staining/contrasting: osmium tetroxide
- Dehydration: series with ethanol - and staining/contrasting: 70%ethanol with uranyl acetate
- Intermediate solvent: propylene oxide
- Embedding: synthetic resins
- Preparation of semithin and ultrathin sections
- Staining/contrasting: lead citrate
Definition and classification of epithelial tissue
Tisse that covers external and internal body surfaces, cavities and tubes. For selective diffusion, absorption, sensory function and physical protection. Avascular and innervated.
5 types: surface-, glandular-, absorptive-, pigment- and sensory epithelia.
Classification:
-Simple (one layer): squamous, cuboidal and columnar
-Stratified (several layers): - - -
-Pseudostratified
-Transitory
The epithelial cell layers and connections
Layers: Apical, lateral and basal
Connections: Tight junctions, gap junctions and belt desmosome
Simple epithelia
- Squamous: Thinnest. Allows transport, secretes fluid, lines cardiovascular system, cover organs and forms capsules in kidney.
- Cuboidal: Round nuclei. Forms ducts, tubules and secretory cells in exocrine glands and kidney.
- Columnar: Nuclei towards basal lamina in elongated cell. Absorbe digestive nutritions and secretes mucous, enzymes and other substances.
Pseudostratified and transitory epithelia
- Pseudostratified columnar: Single layer of cells. Nuclei in more than one level.
- Transitory: 3-5 cells thick. In urinary tracts - stretches.
Stratified epithelia
- Squamous: non-keratinized and keratinized
- Non-keratinized: stratum basale, -spinosum and -planocellulare.
- Keratinized: stratum basale, -spinosum, -granulosum, -lucidum and -corneum. Skin and GI tract.
- Cuboidal: Rare. 2 rows. Sweat glands.
- Columnar: stacked columnar cells. Excretory ducts, larynx and urethra.
Classification of glands
- By nr of cells: uni- or multicellular.
- By position: intra-/endoepithelial or extra-/exoepithelial
- By transport of secretion: with ducts - exocrine or without - endocrine
- By morphology of acini: tabular, acinar or tabuloacinar
- By mode of secretion: merocrine, apocrine or holocrine
- By secretory-product: serous, mucous or seromucous
Modes of secretion
- Merocrine: Exocytosis. In pancreas.
- Apocrine: Apocrine portion of cell pinched off
- Holocrine: Cell dies
Serous, mucous and seromucous acini
- Serous: Cell with narrow lumen, round basal nuclei, basophilic cytoplasm and prod. enzymes. Pancreas.
- Mucous: Cell with wide lumen, flattened basal nuclei, poor stained cytoplasm and prod. mucopolysaccharides. Esophagus.
- Seromucous: Largest cell with mucous acini rounded by serous cells that forms a semilunar cap.
Definition and classification of CT
Tissue origination from mesenchyme of embro, which provides structural and metabolic support for organs and tissue, and bind tissues together to form organs and organisms. Densely vascularized and innervated. Composed of fixed and free cells and ECM with ground substance and fibers.
- Embryonic: Mesenchyme and gelatinous
- Adult: Chordoid, adipose, reticular, loose and dense (regular and irregular)
ECM of CT
- Ground substance: Highly hydrates gel which surround cells and fibers. Composed of proteoglycan and GAG´s bound to a protein core.
- Fibers: connective, elastic, collagen or reticular
Cell types of CT
- Fixed: fibroblast, fibrocyte, mesenchymal and adipose cells
- Free: macrophages, mast cells, plasma cells, melanocytes and lymphocytes, moncytes and granulocytes
Embryonic connective and supportive tissue types
- Mesenchyme: 3D-network of irregular-shaped cels and abundant ground substance. Lacks fibers.
- Gelatinous: Of stellate fibroblasts, amorphous ground substance and collagen fibrils.
- Chordoid: More supportive. Found in notochord. Fill with water.
Adult CT types
- Loose: Free and fixed cells dominates, collagen, elastic and reticular fibres and ground substance
- Dense irregular: Bundles crossing at varying angles. Collagen fibres, fibroblasts and fibrocytes dominate.
- Dense regular: Collagen fibres arranged in same plane and direction.
- Reticular: Of stellate reticular cells and 3D-network of reticular fibres.
- White adipose: Unilocular adipocytes, collagen and reticular fibres.
- Brown adipose: Multilocular adipocytes, collagen and reticular fibres.
Blood as connective tissue: plasma and cellular compounds
Fluid CT that carries/transport
- Cellular components: erythrocytes, thrombocytes and leukocytes
- ECM: Plasma (water with solutes) and fibres (fibronogen for clotting).
Morphology and function of eruthrocytes
Red blood cells.
- Cell shape: non-nucleated and biconcave, shallow concavity or flat
- Abnormalities: Poikilocytosis, Roulaux formation, Howell-Jolly bodies and reticulocyte
- Function: Contain hemaglobin which carries O2.
Morphology and function of thrombocytes
- Colourless, anucleated curpuscles. Thin biconvex discs.
- Blood clotting
Granulocytes
- Polymorphonuclear
- Neutrophils: Most segmented nuclei. Phagocytose.
- Eosinophils: Bilobed nuclei. Control allergic reactions, phagocytose and defend against parasittic worms.
- Basophils: U- or kidney-shaped nuclei. Function as CT mast cells. Contain histamine and heparine.
Agranulocytes
- Mononuclear.
- Lymphocytes: Large nucleus with thin cytoplasmic rim. Develope into B- and T-lymphocytes. Provide immunity.
- Monocytes: Large kidney-shaped nuclei. Transform to macrophage.
Comparison between mammalian and avian blood
- Erythrocytes: In mammalian it´s round discs with no nuclei. In avian it´s nucleated ovoid cells.
- Thrombocytes: In mammalian it´s biconvex discs, no nuclei and called platelets. In avian it´s nucleated ovoid cells which is not platelets.
- Granulocytes are called heterophils in avian blood.
Prenatal and postnatal hematopoiesis
- Prenatal: Begin in wall of yolk sac. Migrate to liver. From liver to bone marrow, spleen, lymph nodes and thymus of embryo where it begins hematopoiesis.
- Postnatal: Major occur in bone marrow, also liver and spleen. As demand for blood cells decrease with age, red replaced by yellow bone marrow.
Structure of bone marrow and hematopoietic stem cells
- BM: Soft, flexible, CT within bone cavities, that lacks lymphatic vessels, but is innervated.
- Hematopoietic compartments: of irregular tabular cords lying between vascular sinuses.
- Hematopoietic stem cells: Pluripotent cells that give rise to myeloid stem cells or lymphoid stem cells.
Stages of erythrocyte cell line
- CFU-E
- Rubriblast
- Prorubricyte
- Basophilic rubricyte
- Metarubricyte
- Reticulocyte
Stages of granulocyte cell line
- CFU-GM
- Myeloblast
- Promyelocyte
- Myelocyte
- Metamyelocyte
- Band form
- Mature form
Stages of thrombopoiesis and lymphopoiesis
- Thrombopoiesis: megakaryoblast -> promegakarycyte -> megakaryocyte -> platelets
- Lymphopoiesis: Lymphoid stem cells divide to prod.:
- Pre-B-lymphocyte->B-lymphoblast->B-lymphocyte
- Pre-T-lymphocyte->T-lymphpblast->T-lymphocyte
Types of cartilages
Embryonic: notochord
Adult:
-Hyalin: 2-4 chondrocytes in lacuna, sorrounded by pericellular-, territorial- and interterritorial matrix.
-Elastic: Elastic fibers and single celled chondrons
-Fibrocartilage: Collagen fibres and a few chondrocytes
Tissue component of bone
CT, cells and fibres embedded in non-bending ground substance.
Cells: Osteoblasts, osteocytes, osteons, osteoclasts
Bone matrix: osteoid
-ECM: collagen fibres and GAG´s (flexability) and inorganic compound (firmness)
Desmal(intramembranous) ossification
Bones form directly from layer of embryonic mesenchyme.
Process: Mesechymal cells forms osteoprogenitor cells, which forms osteoblasts. Osteoblast release osteoid, which is calcified. Together they transform into osteocytes.
Chondral ossification
Bones form indirectly, using hyaline cartilage.
Process:
1.Matrix calsify
2.Bone collar formation
3.Capillary loop enters hypertrophic cartilage
4.Chondraclasts phagocytese
5.Mesechymal cells diff. into osteoprogenitor cells->osteoblasts->osteoid
Definition and classification of muscular tissue
Tissue specialized to perform directed, organized movements. Of elongated spindle-shaped cells or elongated muscle fibers. Densely vascularized and innervated.
- Striated: skeletal and cardiac
- Non-striated: smooth
Skeletal muscle
Quick contraction with high fatigue. Impulses generated by motor endplate. Found in locomotor organs (muscles). Myofibrils surrounded by endomysium. Primary bundles covered by perimysium. Muscle ensheated by epimysium.
Cardiac muscle
Quick contraction without fatigue.
Involuntary impulses by cardiac muscle.
Found in heart.
Y-shaped fibre-derived cell with central nucleus. Ertberth´s line borders cell.
Smooth muscle
Slow contractions without fatigue.
Involuntary impulses generated by vegetative plexus.
Found in wall of visceral organs.
Cell that lack striations and perimysium, with central rod-shaped nucleus and outer myosin-bundles.
Molecular basis of muscle contraction
Sarcomere repeats.
- Bordered by Z-lines, with half an isotropin extending toward A-band.
- A-band: H-band and M-line.
- Actin found i Z-line and myosin originate from A-band.
Definition and elements of nervous tissue
Tissue originated from neroectoderm, specialized to generate and conduct impulses. Composed of nerve cells, glial cells and it´s processes.
Densely capillarized.
Main component of CNS and PNS.
The neurone
- Soma: cell body with organelles
- Dendrites: Branching processes
- Axon: Myelinated process
- Polarity: uni-, pseudouni- and bi-, and multipolar.
Types and functions of glial cells
CNS: Ependymal, astrocytes, oligodendrocytes and imcroglial cells PNS: neurolemmocytes (satellite and Schwann cells) Function: -Provide structural support -Form CNS boundary -Insulate axons -Maintain ionic homeostasis -Phagocytose cell debris -Prod. scar tissue
Synapses
- Electrical or chemical
- Isotropic (ion channels) or metabotropic
- Post-synaptic site: axodendritic, axospinous or axosomatic
- Function: excitatory or inhibitory
Structure of a nerve, types and fibers
Myelinated: increase transmission speed, nodes of Ranvier -A-fibres: longest insulated segments -B-fibres: shorter internode lengths -C-fibres: slowests Location: -CNS: myelin sheath of oligodendrocytes -PNS: myelin sheath of Schwann cells Unmyelinated: slower transmission, typically shorter nerves
Classification og blood vessels
- Arteries: from heart to tissue (elastic and muscular: medium caliber, small and arterioles)
- Veins: from tissue to heart (large, medium caliber, small, muscular venules and postcapillary venules)
- Capillaries: between those two. (continious, fenestrated and sinuses)
- Composition: tunica intima, media and adventitia
Arteries
- Elastic: Aorta, prim.branches and pulmonary artery. Resistance vessels.
- Muscular: SM as dom. element in tunica media. Distributor vessels. Has ext. + int. elastic membranes.
Capillaries
Exchange vessels that form network of small diameter thin-walled blood vessels.
- Continious: endothelium completely closed, lamina basalis cont.
- Fenestrated: flattened endothelial cells with pores.
- Sinuses: large diameter and thin walled. Cont. endothelium or fenestrated.
Veins
- Larger lumen and thinner wall than arteries.
- Reservoar vessels.
- Wall with less elastic elements, SM and increased CT.
Layers of the heart
- Endocardium: Inner. Cont. endothelial+thin collagen and elastic fibre layers. SM.
- Myocardium: Cardiac muscle
- Epicardium: Outer. CT within coronaria vessels+visceral pericardium.
Lymphatic vessels
Drainage vessel system that carry excess EC-fliud into circulation.
- Lymphatic capillaries: fine tube-like spaces lined by endothelium, that lack basal lamina and pericytes.
- Lymphatic vessels: like veins histologically
