3CELL THEORY: One of the 3 Theories that unify all knowledge in Biology 1. All living things are made of one or more cells.2. A cell is the smallest thing that can be considered alive. (1839 Schwann & Schleiden )3. All cells come from otherpre-existing cells by reproduction.(1855 Rudolph VirchowCells were first discovered in1663 using one of the firstprimitive microscopes. Theywere cells in cork. Robert Hooke[The word cell is from Latin 'cellula' which means small compartment ]
4Microscope1670’s Anton von Leeuwenhoek – first to observe bacteria and protozoa using a more “advanced” microscope.~ 1833 Robert Brown reported the discovery of the nucleus
5TYPES OF CELLS: A. Prokaryotic SIMPLENo nucleus or othercomplex organelles.b. DNA circular,floating in cytoplasm.2. TINY : .1 – 10 Mm3. PRIMITIVE: Similar tofirst living things.Fossils found up to3.8 billion years old.4. KINGDOM: Monera(example: bacteria)
6TYPES OF CELLS: B. Eukaryotic 1. COMPLEXNucleus + many other complex organelles.b. DNA in nucleus; multiple strands (called chromosomes)2. LARGE: Mm (some up to 2 meters long!)3.ADVANCED: Evolved almost 2 billion years after Prokaryotes.4. KINGDOMS:all members of Protist, Fungi, Plant, Animal5. TYPES:a. PLANTb. ANIMAL
7Each cell in an organism has a specific job. Depending on its function it may look very different from the “typical” plant or animal cell.
8Notes: HOW EUKARYOTIC CELLS EVOLVED The Endosymbiont Theory (“Endo-” = inside; “Symbiosis” = mutually beneficial relationship)1. Mitochondria and chloroplasts were once free-living prokaryotic organisms.2. They entered (or were eaten by!) cells of other organisms and began living there.
93. Helped host cells survive: provided ATP (mitochondria) or glucose (chloroplasts). 4. Host cell provided protection for them.5. And so - they stayed!
10All surrounded by double membranes. Evidence Supporting Endosymbiont Theory – Mitochondria and Chloroplasts are very much like bacteria:All surrounded by double membranes.2. Similar size. a. mitochondria: Mmb. chloroplasts: Mmc. bacteria: 0.5 – 10MmE Coli (bacteria)ChloroplastMitochondria
11Evidence Supporting Endosymbiont Theory - continued 3. Similar ribosomes.4. Both have their own DNA (separate from nuclear DNA of the cell) - circular like bacterial DNA.5. Both reproduce separately from rest of cell - by simple fission, like bacteria.
13Organelles, continued Cytoplasm Cytoskeleton Ribosomes Microtubules Endoplasmic reticulum (rough and smooth)Golgi apparatusLysosomeVacuoleChloroplast (plants only)MitochondriaCytoskeletonMicrotubulesMicrofilaments(good website to learn names and functions of cell organelles)
14CELL ANALOGY: A cell is a lot like a town CELL ANALOGY: A cell is a lot like a town. Its organelles do jobs similar to the functions of some entities in a typical town. Which cell organelle is most like each of the following in terms of the work it does for the cell?Master plan; blueprint.Freeway systemCement factoryFood producers (farmers)Power plant, electricity generators.6. Sewage treatment, waste detoxification7. Water storage tank8. Border control, INS9. Mayor’s office10. Materials packaging & storageChromatin (DNA)LysosomeEndoplasmic ReticulumVacuoleRibosomeCell (plasma) membraneChloroplastNucleusMitochondriaGolgi body
15Review of Animal and Plant Cells Created by T. Bun & J. Cook & E. Coleman
18________ are known as the “power-houses” of the cell because they produce ATP. NucleusMITOCHONDRIA
19The cell membrane is also known as the _______ membrane. What structure controls the movement ofmaterials into and out of the cell?CELL MEMBRANEThe cell membrane is also known as the _______ membrane.PLASMA________ are the sites where proteins are made (“protein synthesis”) in the cell.PlasmaRIBOSOMES
20thing plant cells store in their vacuoles? What is number 6?A vacuole.What is the mainthing plant cells store in their vacuoles?VacuoleWATER
21Number 5 is pointing to what? The CELL WALL.Cell Membrane
22What structures produce glucose and other carbohydrates (i.e. FOOD!)? CHLOROPLASTSChloroplast
23What organelles store primarily enzymes and waste? LYSOSOMESVacuoles
24What is the structure in the nucleus that makes ribosomes and other kinds of RNA? NucleolusNucleolus
25What is structure number 13? PC diagramCentriolesCENTRIOLE
26What type of cells are these? Cheek CellsHUMAN CHEEK CELLS
27What type of cells are these? ELODEA CELLSWhat are the little green things inside them?CHLOROPLASTS
28What kind of cells are these? ONION CELLSOnions are plants. Why are there no chloroplasts in these cells?This part of the plant grows underground. Chloroplasts do photosynthesis – that requires light. There’s no point in having chloroplasts in cells that aren’t exposed to light!
29Number 6 is pointing to what structure? Golgi BodyGOLGI BODY (aka GOLGI APPARATUS, GOLGI COMPLEX)
30CHLOROPLASTS and CELL WALLS The two structures found in plant cells that are never found in animal cells are ____________ & ___________.CHLOROPLASTS and CELL WALLSCell Wall and Chloroplast