PM-132 Introduction to Cell Biology Handouts PDF

Aled.Roberts @ Swansea.ac.uk EukaryoticCell Biology Introduction toCell Biology PM-132 1 Learning Objectives: Understand how atoms transitioned into molecules and then into...

Aled.Roberts @ Swansea.ac.uk EukaryoticCell Biology Introduction toCell Biology PM-132 1 Learning Objectives: Understand how atoms transitioned into molecules and then into cells. Know what is meant by the term “cell”, and describe the differences between Eukaryotic and Prokaryotic cells. Describe the central dogma theory of molecular biology. Describe the different cells found in the body, and understand how the “division of labour” allows cells to carry out specific functions. 2  Life: In the beginning… Life is thought to have emerged some 3.8 billion years ago. 3 Life: In the beginning… Life is thought to have emerged some 3.8 billion years ago. 750 million years after Earth formed 4  Life: In the beginning… Life is thought to have emerged some 3.8 billion years ago. 750 million years after Earth formed Organic molecules Macromolecules 5 Life: In the beginning… Life is thought to have emerged some 3.8 billion years ago. 750 million years after Earth formed Organic molecules Self-replicating Macromolecules 6  Organic Molecules: Created when molecules in the atmosphere were exposed to sunlight and/or electrical discharge… 7 Organic Molecules: Created when molecules in the atmosphere were exposed to sunlight and/or electrical discharge… 8  Organic Molecules: Amino acid Created when molecules in the atmosphere were exposed to sunlight and/or electrical discharge… 9 Organic Molecules: Miller‐Urey Experiment 10  Organic Molecules: Miller‐Urey Experiment 11 Organic Molecules: Miller‐Urey Experiment 12  RNA World: It is thought the “RNA World” started some 4 billion years ago and preceded the first cells that contained DNA. RNA 13 RNA World: Initial genetic system with important features It is thought the “RNA World” started some 4 billion years ago and preceded the first cells that contained DNA. 14  RNA World: Catalyse reactions Acts as a template Self replicating Initial genetic system with important features It is thought the “RNA World” started some 4 billion years ago and preceded the first cells that contained DNA. 15 RNA:Templates Acts as a template Complementary base pairing turns single strands into complex shapes Non‐folded strand Four‐Stem Junction Three‐Nucleotide Bulge Pseudoknot Hairpin loop 16  RNA: Catalyse Reactions Catalyse reactions Simple interactions can lead to the One strand creation of new “usable” molecules recognises a template One strand acts as a template 17 RNA: Catalyse Reactions Catalyse reactions Simple interactions can lead to the creation of new “usable” molecules Binding via the process of base pairing, causing stress in the template 18  RNA: Catalyse Reactions Catalyse reactions Simple interactions can lead to the creation of new “usable” molecules New usable molecules created which may now have a unique function… 19 RNA: Catalyse Reactions: Ribozymes Peptide bond formation Ribosomal RNAs DNA cleavage and RNA ligation Self‐splicing RNAs, RNAse P RNA cleavage and splicing Self‐splicing RNAs RNA polymerisation RNA/DNA phosphorylation In vitro selected RNAs RNA aminoacylation RNA alkylation Glycosidic bond formation Carbon‐carbon bond formation Phosphoamide bond formation In vitro selected RNAs Disulfide exchange Redox reactions 20  Central Dogma: of molecular biology Translation Protein RNA Replication 21 Central Dogma: of molecular biology Translation Protein Transcription RNA DNA Replication 22  Central Dogma: of molecular biology Translation Protein Transcription RNA DNA All of the DNA within an cell is known as its genome Replication with functional units called genes 23 Genome Size: Methanococcus jannaschii 1700 genes, 1.7 mbp Mycoplasma genitalium 530 genes, 0.58 mbp Escherichia coli 4300 genes, 4.6 mbp Saccharomyces cerevisiae 6000 genes, 12 mbp Paramecium spp. 39500 genes, 72 mbp Volvox spp. 14500 genes, 138 mbp Arabidopsis thaliana 26000 genes, 125 mbp Corn plants 33000 genes, 2200 mbp Apple plants 57000 genes, 740 mbp Caenorhabditis elegans 19000 genes, 97 mbp Zebra fish 20‐25000 genes, 1700 mbp Humans 20‐25000 genes, 3000 mbp 24  The Cell: “ first discovery " Robert Hooke English Physicist 1665 Used the light microscope to image thin slices of cork, identifying compartments… 25 The Cell: “ first discovery " Robert Hooke English Physicist 1665 Used the light microscope to image thin slices of cork, identifying compartments… 26  The Cell: CellTheory Matthias Schleiden Theodor Schwann German Botanist and Physiologist 1839 “we have seen that all organisms are composed of essentially like parts, namely cells” 27 The Cell: CellTheory Rudolf Virchow German Physician and Pathologist 1858 “every animal appears as a sum of vital units, each of which bears in itself the complete characteristics of life” 28  The Cell: CellTheory Rudolf Virchow German Physician and Pathologist “ omniscellula e cellula ” Every cell arises from another 1858 “every animal appears as a sum of vital units, each of which bears in itself the complete characteristics of life” 29 The Cell: CellTheory 1. All organisms consist of one or more cells 3 principles 2. The cell is the basic structural unit of all organisms 3. All cells arise from existing cells only 30  The Cell: What is a cell? 1. Cells are small 2. Cells are “membrane enclosed” 5 Features 3. Cells are contain an aqueous solution 4. Cells create self copies of themselves 5. Cells divide in two 31 Multicellular Organism: What is an organism? 1. Movement 2. Respiration 3. Sensitivity 7 Features aka Mrs Gren 4. Growth 5. Reproduction 6. Excretion 7. Nutrition 32  Branches of Life: Archaea eukaryotes prokaryotes Human Sulfolobus Bacteria Haloferax Aeropyrum Maize Yeast Methano‐ Cyanobacteria thermobacter Paramecium Bacillus Methanococcus Dictyostelium Escherichia Euglena Trypanosoma Giardia Thermotoga Aquifex Common Trichomonas Ancestor 33 The Prokaryotic Cell: Plasmids ribosomes pili Super coiled DNA cytoplasm Flagellum Plasma membrane Inner Outer 34  The Eukaryotic Cell: Intermediate filaments Plasma membrane mitochondria cytoplasm Chromatin Micro-filaments nucleolus Microtubule nucleus Rough ER peroxisome centrosome ribosomes Golgi apparatus Golgi vesicle Smooth ER vacuole Lysosome Secretory vesicles 35 Eukaryotic vs. Prokaryotic: Comparison… 10 ‐ 100 μm Size… *It’s all relative (Diameter) ~1 μm Large* Small* 36  Eukaryotic vs. Prokaryotic: Comparison… Organelles? Present Nucleus ? Absent The same goes for all other “membrane bound” organelles 37 Eukaryotic vs. Prokaryotic: Comparison… Multiple, linear DNA Genome… Single, circular DNA Size: 15 million to 5 billion bp Size: 1 million to 5 million bp 38  Branches of Life: Archaea eukaryotes prokaryotes Human Sulfolobus Bacteria Haloferax Aeropyrum Maize Yeast Methano‐ Cyanobacteria thermobacter Paramecium Bacillus Methanococcus Dictyostelium Escherichia Euglena Trypanosoma Giardia Thermotoga Aquifex Common Trichomonas Ancestor Emergence of First eukaryote 39 The Eukaryotic Cell: Emergence? 40  The Eukaryotic Cell: Emergence? 41 The Eukaryotic Cell: Emergence? 42  The Eukaryotic Cell: Emergence? 43 The Eukaryotic Cell: Emergence? 44  Cellular Differentiation: Uni‐cellular evolved into multi‐cellular organisms between 1 and 2 billion years ago. *Dates may vary depending on source 45 Cellular Differentiation: Uni‐cellular evolved into multi‐cellular organisms between 1 and 2 billion years ago. Volvox spp. Multicellular (2 cell types) *Dates may vary depending on source 46  Cellular Differentiation: Uni‐cellular evolved into multi‐cellular organisms between 1 and 2 billion years ago. Volvox spp. Amoeba spp. Multicellular (2 cell types) Uni‐cellular *Dates may vary depending on source 47 Cellular Differentiation: Uni‐cellular evolved into multi‐cellular organisms between 1 and 2 billion years ago. Volvox spp. Amoeba spp. Amoeba spp. Multicellular (2 cell types) Uni‐cellular Uni‐cellular *Dates may vary depending on source 48  Cellular Differentiation: Uni‐cellular evolved into multi‐cellular organisms between 1 and 2 billion years ago. Volvox spp. Amoeba spp. Amoeba spp. Multicellular (2 cell types) Uni‐cellular –High Nutrients Uni‐cellular –Low Nutrients *Dates may vary depending on source 49 Specialisation of Cells: 50  Specialisation of Cells: Humans 1. Epithelial tissue 2. Connective tissue 5 tissue types 3. Blood 4. Nervous tissue 5. Muscle tissue 51 Specialisation of Cells: Humans 1. Epithelial tissue 2. Connective tissue 5 tissue types 3. Blood 200 cell 4. Nervous tissue types 5. Muscle tissue 52  Specialisation of Cells: “Division of Labour” 1. Epithelial tissue 2. Connective tissue 5 tissue types 3. Blood 200 cell 4. Nervous tissue types 5. Muscle tissue 53 Humans: Cell Differentiation Mouth epithelial cells Connective tissue fibroblasts 54  Humans: Cell Differentiation Lymphocytes Monocyte Eosinophil Basophil 55 Aled.Roberts @ Swansea.ac.uk EukaryoticCell Biology Introduction toCell Biology PM-132 56