Lecture 04 Cell structure and function.pdf

1 202101(c)2023. Department of Biology, CMU. All right reserved.   The Fundamental Unit of Life  What is Cell?  Cell Theory  Unicellular and Multicellular Organisms  Tools for Cell Study  Cell size and shape  Cell and O...

1 202101(c)2023. Department of Biology, CMU. All right reserved.   The Fundamental Unit of Life  What is Cell?  Cell Theory  Unicellular and Multicellular Organisms  Tools for Cell Study  Cell size and shape  Cell and Organelles 2 202101(c)2023. Department of Biology, CMU. All right reserved. https://ak3.picdn.net/shutterstock/videos/6726283/thumb/1.jpg?ip=x480   Basic unit of living organism  Cell character:  มีขอบเขตชัดเจน  เพิม่ จำนวนได้ – มีสำรพันธุกรรม  สังเครำะห์สำรได้  สร้ำง/ใช้พลังงำนได้ https://previews.123rf.com/images/sinhyu/sinhyu2011/sinhyu201100118/159016 636-education-spinal-cord-and-motor-neuron-under-the-microscope-in-lab.jpg 3 202101(c)2023. Department of Biology, CMU. All right reserved.  1. All organism are made up of one or more cells 2. All cell arise from pre-existing cells 3. Cell is the structural and functional unit of life 4 202101(c)2023. Department of Biology, CMU. All right reserved. 5 202101(c)2023. Department of Biology, CMU. All right reserved.  Euglena Paramecium Yeast Plant Animal Fungi 6 202101(c)2023. Department of Biology, CMU. All right reserved.   Vary in size  Most cells are very small (m)  Some may be very large 7 202101(c)2023. Department of Biology, CMU. All right reserved.  Smallest cell Largest cell Longest cell Sperm cell Ovum cell Nerve Cell Size: 5 m Size: 120 m Size: 1 m 8 202101(c)2023. Department of Biology, CMU. All right reserved.  Human RBCs Nerve Cell Human WBCs Shape : circular Shape: branched to Shape: shape shifting to biconcave for traveling conduct impulse from engulf the microorganism through human capillaries one point to another that enter the body 9 202101(c)2023. Department of Biology, CMU. All right reserved.   Observe under microscope  Detailed structure of cell  Light microscope  Electron microscope  Certain structures only see under EM - ultrastructure 10 202101(c)2023. Department of Biology, CMU. All right reserved.  Stereo Microscope Compound Microscope 11 202101(c)2023. Department of Biology, CMU. All right reserved.  Transmission Electron Microscope - TEM Scanning Electron Microscope - SEM 12 202101(c)2023. Department of Biology, CMU. All right reserved.   Study of living cells  Time-lapse microscopy  Obtain a better understanding of biological function  Microcinematographic films of cells 13 202101(c)2023. Department of Biology, CMU. All right reserved.  12 1..................... 1 2..................... 2 3..................... 3 4..................... 5..................... 11 4 6..................... 10 7..................... 9 8..................... 9..................... 8 10..................... 7 6 5 11..................... 12..................... 14 202101(c)2023. Department of Biology, CMU. All right reserved.  1..................... 1 2 2..................... 12 3..................... 13 4..................... 5..................... 3 6..................... 7..................... 11 4 8..................... 10 9..................... 5 10..................... 9 6 11..................... 7 12..................... 8 15 202101(c)2023. Department of Biology, CMU. All right reserved. 13.....................  1................... 2.................... 3.................... 4.................... 5.................... 6.................... 7.................... 8.................... 9.................... 10.................... 16 202101(c)2023. Department of Biology, CMU. All right reserved.   3 structures common to most cells  Cell membrane - boundary  Nucleus (only in eukaryote)  Cytoplasm –material between membrane and nucleus  Cytosol  Cell organelles 17 202101(c)2023. Department of Biology, CMU. All right reserved.   Dense spherical body located near the center of the cell  Most are uninucleated  Double layers of nuclear membrane with 80-100 nm pores  Nucleoplasm, nucleolus, network of chromatin fibers  DNA and protein histone 18 202101(c)2023. Department of Biology, CMU. All right reserved.   Chromosome contain DNA, genes Functions  Control all cell activities  Synthesizes RNA  Store hereditary information in gene 19 202101(c)2023. Department of Biology, CMU. All right reserved.   Area between nucleus and plasma membrane  Jelly-like material – 80% water  Cytosol – clear liquid portion  Particles – proteins, carbohydrates, nucleic acid, lipids and inorganic ions  Contain many organelles  Some visible under LM  Some visible under EM 20 202101(c)2023. Department of Biology, CMU. All right reserved.   Extensive membrane network within the cytoplasm  Membrane-bound structures in cytoplasm of most eukaryotic cells  ER, Golgi complex, endosome, lysosomes, vacuoles  Part of a dynamic, integrated transportation network  Biosynthetic/Secretory pathway 21 202101(c)2023. Department of Biology, CMU. All right reserved.   Manufactures & Shippers  Network of connected tubular and vesicular structures  2 types – Smooth and Rough ER Functions:  Internal support to cytoplasm  RER – secretory protein/membrane protein  SER – lipid membrane, detox 22 202101(c)2023. Department of Biology, CMU. All right reserved.   A stack of 5-8 membrane sacs  Cisternae - flattened sacs  2 ends – cis and trans faces Functions:  Modified, sorts and packs materials  Delivers synthesized materials to various targets, in and outside  Vacuoles, secretory vesicle, lysosome, plasma membrane 23 202101(c)2023. Department of Biology, CMU. All right reserved.  Biosynthetic/secretory pathway  From ER through the Golgi complex  Out to various location  Lysosome  Endosome  Secretory vesicles  Vacuoles  Plasma membrane 24 202101(c)2023. Department of Biology, CMU. All right reserved.   Small, sphere, single membrane sacs  Filled with hydrolytic enzymes  Found in most animal cells, few in plant cells Functions:  Digest large molecules  Protect cell  Degradation of organelles  Autolysis of dead cells 25 202101(c)2023. Department of Biology, CMU. All right reserved. 26 202101(c)2023. Department of Biology, CMU. All right reserved.   Single membrane sac  Filled with liquid, water, sugar, ions  Animal – temporary, small and few  Plant – large and more in number Functions:  Store various substances, waste products, food storage in amoeba cells  Maintain osmotic pressure  Provide turgidity and rigidity to plant cells 27 202101(c)2023. Department of Biology, CMU. All right reserved. 28 202101(c)2023. Department of Biology, CMU. All right reserved.   Small, rod shaped with bound by two layers of membranes  Outer – encloses the content  Inner – folded called cristae  Inner cavity – matrix contains many enzymes and DNA Functions:  Synthesize ATP 29 202101(c)2023. Department of Biology, CMU. All right reserved.  Plastids  Double membrane bound  Found inside plants and some algae  Activities related to making or storing food  Contain different types of pigments 30 202101(c)2023. Department of Biology, CMU. All right reserved.  Pigment: Carotene Carrot  Plastids that produce and Pigment: Xanthophyll store pigments Mango  Different colors found in Leaves, fruits, flowers, vegetables Pigment: Lycopene Tomato 31 202101(c)2023. Department of Biology, CMU. All right reserved.  Food: Starch Potato tubers  Colorless plastid Food: Protein  Store food Maize grains  Found in storage organs  Fruits  Tubers  Seed Food: Oil Castor seed 32 202101(c)2023. Department of Biology, CMU. All right reserved.   Double membrane-bound organelle  Found mainly in plant cells  2 regions – Grana and Stroma  Grana – stake of flatten membrane-bound disc, Thylakoid  Stroma – dense fluid Functions:  Convert light E to chemical E – food 33 202101(c)2023. Department of Biology, CMU. All right reserved. 34 202101(c)2023. Department of Biology, CMU. All right reserved. 35 202101(c)2023. Department of Biology, CMU. All right reserved.  Microtubule Microfilament/Actin Intermediate filament Hollow tube make of Solid filament of protein, Compose of several protein, tubulin dimers actin dimer different types of proteins Support, move organelle Determine the cell shape Provide structural support through cells, cell division Cellular movement Mechanical strength (centriole, spindle fiber) Cytokinesis, Cyclosis, Scaffolding Cilia, Flagellum Amoeboid movement Not found in yeast, plants 36 202101(c)2023. Department of Biology, CMU. All right reserved.   Two layers of lipid molecules in which protein molecules are floating  Thin (75-110 A°), elastic, living and semi permeable membrane Functions:  Maintain shape and size, homeostatis  Protects internal contents of the cell  Regulates transport across membrane 37 202101(c)2023. Department of Biology, CMU. All right reserved.  Non-living, covering of a cell (plant and bacteria)  Made up of cellulose, hemicellulose, pectin  Thin/thick, multilayer structure (50-1000 A°) Functions:  Provide shape, strength, rigidity  Prevent cell from drying  Controlling cell expansion  Protect from pathogens 38 202101(c)2023. Department of Biology, CMU. All right reserved.   Several types of ECM  Proteins – collagens  Polysaccharides – Glycosaminoglycans, Proteoglycans  Basal laminae – support epithelial cells,  Abundant in connective tissues, bone, tendon  Functions:  Mechanical supporting 39 202101(c)2023. Department of Biology, CMU. All right reserved.   Direct interactions between cells  Critical to development of Multicellular organisms  Provide Cell Adhesion  Provide mechanism for rapid communication between cells  Animal cells – cell junctions  Plant cells - plasmodesmata 40 202101(c)2023. Department of Biology, CMU. All right reserved.   Tight Junctions  Functions: sealing extracellular space  Adheren and Desmosome Junctions  Functions: binding cell to neighbor cells and mechanical stress  Gap Junction  Functions: intercellular communication 41 202101(c)2023. Department of Biology, CMU. All right reserved.   Cytoplasmic channels pass through cell wall of adjacent cells  Lined by plasma membrane and contain desmotubule (SER) Functions:  Connected to another cells  Cell-to-cell communication  Substance up to 50 KDalton 42 202101(c)2023. Department of Biology, CMU. All right reserved.  Prokaryotic Cell  Eukaryotic Cell 1. Nucleus is undeveloped 1. Nucleus is well developed 2. Only one chromosome present 2. More than one chromosome are 3. Membrane bound organelles are present absent 3. Membrane bound organelles are 4. Size ranges from 0.5-5 m present Ex. Bacteria and Blue green algae 4. Size ranges from 5-100 m Ex. All other organism 43 202101(c)2023. Department of Biology, CMU. All right reserved.