Lecture 4 - From Cell to Organism (2024) PDF

From cell to organism drg. Yustina Andwi Ari Sumiwi, M.Kes Saihas Suhda, S.Si., M.Si., Ph.D Department of Histology and Cell Biology Faculty of Medicine, Public Health, and Nursing Universitas Gadjah Mada Learning objectives Understand...

From cell to organism drg. Yustina Andwi Ari Sumiwi, M.Kes Saihas Suhda, S.Si., M.Si., Ph.D Department of Histology and Cell Biology Faculty of Medicine, Public Health, and Nursing Universitas Gadjah Mada Learning objectives Understand the structure and function of cells, organelles and cytoskeleton Understand tissue structure and function (epithelium, connective tissue/textus connectivus, muscle tissue/textus muscularis, nerve tissue/textus nervosus) Understand the association between cell and extracellular matrix/matrix extracellularis Cell: the smallest functional unit of an organism The main molecules that compose cell A cell is a unit that is enveloped by a membrane Two main compartments in a cell: nucleus dan cytoplasm. Cytoplasm consists of cytosol, organella, and cytoskeleton. The plasma membrane is a lipid bilayer, separating the cell from the extracellular environment Phospholipid is amphiphatic polar plasma membrane: selective barrier non-polar Only a specific molecule can pass through the plasma membrane freely Function of plasma membrane Communication Physical barrier: protects intracellular component and supports cell structure Movement Cellular transport regulates the transportation of molecules into and out of the cell maintains ions gradient from the extracellular fluid Cell components - Nucleus - Cytoplasm contained of cytosol, cytoskeleton, and organelles Nucleus: control and data center A house of genetic material (deoxyribonucleic acid, DNA) that contained of ‘instruction’ to synthesize a protein for cellular processes. nucleus cytoplasm  Nucleus is enveloped by a porous membrane which is continuous with the membrane of reticulum endoplasmicum Nucleus produces the ribosomal subunit in nucleolus Cytosol characterized by a gel-like structure contents: water, ions, macromolecules a house of cytoskeleton Cytoskeleton a. microtubulus b. microfilamentum c. Filamentum intermedium  Microtubules are dynamic structure Microtubules form a basic structure of cilium dan flagellum Composed of α dan β tubulin heterodimer. Undergo continuous polymerization and depolymerization cycle Microtubulus: the cell’s highway Orange: microtubulus Involved in intracellular transport (vesicles, macromolecules, mitochondria) and organella’s distribution (reticulum endoplasmicum, apparatus golgiensis) Supported by motor protein: kinesin & dynein Microfilamentum/ filamentum actini Composed of monomer actin A dynamic structure Along with myosin → generates force for contraction and movement of muscle cells/myocytus  filamentum lamin on nucleus membrane Filamentum intermedium Composed of different protein on different type of cell Green: filamentum GFAP on astrocytus intermedium GFAP: glial fibrillary acidic protein Keratinocytus = skin epithelial cell Astrocytus = glial cell neurofilamentum on neuron filamentum keratini on keratinocytus Neuron = nerve cell Organella Organella: cell’s subunit with specific functions Membrane-enclosed organella: reticulum endoplasmicum, mitochondrion, lysosoma, peroxysoma, apparatus golgiensis Nonmembrane-enclosed organella: ribosoma, proteasoma, centrosoma  Ribosoma: a protein manufacture Ribosoma composed of large and small subunit for protein (amino acid chain/polypeptide) synthesis Distribution: “free” at cytoplasm or attached to reticulum endoplasmicum Polyribosoma: some of ribosoma bind to one of mRNA Protein imported to nucleus, Lysosomal mitochondria, peroxisoma protein Reticulum endoplasmicum granulosum (rough ER) A branched and interconnected flattened-sacs → ER sheet Functions: protein folding and modification (e.g. glycosylation) Well-developed in the cell specializing in protein production Plasmocytus acinocytus pancreaticus Fibroblastus Reticulum (plasma cell) (pancreatic acinar cell) (fibroblast cell) endoplasmicum granulosum Reticulum endoplasmicum nongranulosum (smooth ER) An interconnected tubules branched from RE granulosum → ER tubules Functions: synthesize phospholipid and steroid detoxification of molecules (e.g. drugs, alcohol) glycogen metabolism (in hepatocytus/liver cell) Reticulum calcium storage (in myocytus) endoplasmicum nongranulosum Apparatus golgiensis: a center for packaging Composed of layers of an organized membranous disc (cisterna) A place to modify protein by glycosylation, phosphorylation, etc Pack and deliver the protein to targeted destinations (lysosoma, plasma membrane, secreted out of the cell)  Lysosoma macrophagocytus Function: digest malfunctioning intracellular organella and material taken in from outside of the cell. Contains of hydrolytic enzymes Abundant in the cells that are play a role in phagocytosis lysosoma Peroxysoma Function: breaks down fatty acid (e.g. beta oxidation of long chain of fatty acid) plays a role in a formation of bile acid and cholesterol detoxification of harmful substances Contains of enzymes for oxidative reactions (e.g. catalase decomposes H2O2 into 2H2O + O2) peroxisoma  Proteasoma Function: eliminate non-functional protein excess protein viral protein  Mitochondrion: an energy plant Has its own DNA, mitoribosoma, mRNA, tRNA in the matrix membrana Generates energy: mitochondrialis externa matrix mitochondrialis ATP (adenosine triphosphate) crista spatium heat/thermal mitochondrialis intermembranosum Abundant in the cells with high membrana metabolic activity mitochondrialis interna hepatocytus Myocytus cardiacus Epitheliocytus tubulus distalis The number of organelles are depend on the cell’s specific function a: cells make a few or no protein and secretion b: cells synthesize, segregate and store protein in specific granules c: cells synthesize and pack abundant of protein to be secreted immediately d: cells synthesize, pack, and store abundant of protein in a secretory granules at apical area How cells form a tissue?  Tissue: Cells & matrix extracellularis Matrix extracellularis Noncellular component of a tissue: Fibra (fibre) Substantia fundamentalis (ground substance) Each type of tissue has a specific matrix extracellularis Physical support for cells Initiate biochemical and biomechanical signal required for morphogenesis, differentiation, and homeostasis Matrix extracellularis components Fibra (fibre) Fibra collageni Fibra reticularis Fibra elastica Matrix extracellularis components Substantia fundamentalis (ground substance) Proteoglycan Aggrecan, syndecan consists of core protein & glycosaminoglycan Multiadhesive glycoprotein Fibronectin, laminin Glycosaminoglycan Chondroitin sulfate, keratan sulfate Function: Barrier, lubricant Fill in intercellular space and space between fibra Figure 20-17b Essential Cell Biology (© Garland Science 2010)  The 4 basic tissues and their characteristics Terminologia histologica Epithelial tissue = epithelium = textus epithelialis Connective tissue = textus connectivus Muscle tissue = textus muscularis Nervous tissue = textus nervosus The 4 basic tissues can be found in an organ  1. Epithelium/ textus epithelialis Surface epithelium Lining the surface or cavities of body Membrana basalis Glandular epithelium Epitheliocytus (epithelial cell) has been modified into secretory cell Membrana basalis (basement membrane) = basal lamina and underlying reticular lamina Epithelium LATERAL More cellular component than matrix extracellularis Cells are interconnected by intercellular junction/junctiones intercellulare Polarity of epitheliocytus Apical side: faces the surface Basal side: faces the underlying tissue and Figure 20-19 Essential Cell Biology (© Garland Science 2010) attaches to membrana basalis Supported by lamina propria (textus connectivus) Avascular Membrana Has the ability to regenerate Vasa basalis Function: sanguinea Protection -- lining the surface or cavities of body Lamina propria (textus connectivus) Secretion -- glandula Glandula Absorption Sensor -- detects stimuli Epitheliocytus is tightly connected to the lateral and basal structure to create an effective barrier Zonula occludens Zonula adhaerens Macula adhaerens/ desmosoma Macula communicans/ nexus Hemidesmosoma  Classification of surface epithelium Based on number of layer Simplex (a layer) Stratificatum (many layers) nama berdasarkan bentuk sel paling permukaan/ apical Based on the shape of epitheliocytus squamous cuboidal columnare Type of epithelium: combines number of layer and the shape of epitheliocytus Epithelium simplex cuboideum Figure 20-18 Essential Cell Biology (© Garland Science 2010) Epithelium stratificatum squamosum  Glandular epithelium Glandula exocrina Glandula endocrina secrets molecules a “ductless” glands through ductus to the secrets molecules surface or cavities of (hormones) delivered body through vasa sanguinea to the target organ  2. Textus Connectivus (connective tissue) More matrix extracellularis than cellular component Cellular component: Fixed cell Fibroblastus, myofibroblastus, adipocytus (fat cell), mastocytus (mast cell: component of immune cell) Wandering cell Lymphocytus, dendrocytus (dendritic cell) Fibroblastus synthesizes the matrix extracellularis components (fibra & substansia fundamentalis) Fibroblastus: spindle-like shape cell  Classification of textus connectivus Textus Textus textus connectivus connectivus connectivus laxus/ areolaris compactus proprius Textus Textus Textus Textus textus osseus connectivus connectivus connectivus adiposus compactus compactus reticularis textus cartilagineus irregularis regularis sanguis Textus osseus = bone tissue e.g.dermis e.g. tendo, Textus cartilagineus = cartilago tissue ligamentum Epithelium vs textus connectivus laxus vs textus connectivus compactus Figure 23-1a (part 2 of 2) Molecular Biology of the Cell fibra substantia (© Garland Science 2008) fundamentalis  Tendo & ligamentum are textus connectivus compactus regularis Tendo: connects muscle to bone, strong and non flexible Ligamentum: attaches one bone to another, elastic and flexible Textus connectivus compactus regularis (dense regular connective tissue) Matrix extracellularis: fibra collageni and fibroblastus are parallel-oriented Function: support the structure, provide resistance to prolonged and repeated stresses (pulling, stretching) from the same direction Dermis comprises of textus connectivus compactus irregularis (e.g. submucosa layer of tractus digestivus, capsula fibrosa of joint) Textus connectivus compactus irregularis Matrix extracellularis: fibra collageni & fibra elastica are arranged irregularly Function: provide resistance to stresses from all directions support the structure Textus connectivus laxus (loose connective tissue) Matrix extracellularis: gel-like matrix, abundant of substantia fundamentalis, few of fibra components Function: envelopes organ, as a cushion, maintains the body’s fluid in tissue e.g. lamina propria  3. Textus muscularis (muscle tissue) Textus muscularis striatus non Textus muscularis striatus cardiacus (cardiac muscle Textus muscularis Function: cardiacus (skeletal muscle tissue) nonstriatus (smooth muscle tissue) tissue) Movement Mononuclear (nucleus = 1) Mononuclear (nucleus = 1) (contraction Multinucleare (nucleus >1) Cylindrical shape Long cylindrical shape Fusiform shape and relaxation), interconnected with discus Nucleus at center of the Squamous nucleus at the intercalatus to each other volunter or edge of the cell cell Round nucleus at center involunter Shows striation No striation Shows striation Weak contraction, support Strong & rapid contraction, Strong & rhythmic involunter position and volunter contraction, involunter posture of the body Copyright © McGraw-Hill Companies  4. Textus nervosus (nerve tissue) Function: Detects stimuli Integrates information to the brain Regulates respond and function of the body Cellular components a. Neuron: Dendrite – receives impulse Axon – carries impulse Soma/perikaryon (cell body) b. Neuroglia/ gliocytus (glial cell): support neuron function consists of many types Copyright © McGraw-Hill Companies References Thank you