Review and Introduction to Microscopes
Overview Cell types Discovery Microscopes Reading #1 Reading #2 Diffusion / Osmosis Respiration / Fermentation
Types of Cells Animal (Eukaryote) Plant (Eukaryote) Cell wall- structure large vacuole- wilting chloroplasts (green used for photosynthesis) Bacteria (Prokaryote) Cell wall Small no nucleus
Discovery of Cells 1590’s The invention of the microscope led to the discovery of cells 1663 English: Hooke- introduced the term ‘Cell’ from cork Dutch: Leeuwenhoek- introduced the term ‘animalcules’ – little animals from pond water 1838 German: Cell Theory Schleiden, Schwann, Virchow All living things composed of cells Cells are the basic units of structure and function All cells come from cells
Microscopes Light Microscopes Magnify objects by focusing light through arrangements of lenses (light bends through the lens) convex and concave Simple- one lens Compound- multiple lenses Total magnification is first lens X second lens
Microscopes Electron Microscopes Magnify objects by electron beam instead of light Very high resolution- clarity TEM: Transmission Electron Microscope SEM: Scanning Electron Microscope STM: Scanning Tunneling Microscope
Microscopes
Focus Procedure Turn the course knob all the way down (stage at the lowest point) Rotate to the lowest magnification lens Focus the Diaphragm for light Center specimen in light Use course knob to focus Use fine knob to focus Rotate to next magnification lens ONLY USE FINE FOCUS from this point on!!!
Reading #1 Cellular Organization Unicellular, Multicellular Chemicals of Life Water, carbohydrates, proteins, lipids, nucleic acids Energy Use Where does energy come from Response to Surroundings Stimulus and responses Growth Development Reproduction Redi’s Experiment and Pasteur’s Experiment Living things only come from other living things 4 Basic needs of life (energy, water, shelter, home0statsis)
Reading #2 Elements, Compounds, Molecules Element pure substance, smallest part Compound 2 or more elements bonded Molecules 2 or more atoms bonded Organic and Inorganic Organic contain carbon Inorganic do not contain carbon Carbohydrates: (C,H,O) energy rich, sugar (small), starches (complex, large) Lipids (C,H,O) Energy rich, more energy than carbs, Proteins (C,H,O,N, sometimes S) Large organic molecules Made up of smaller amino acids, linked together in different combinations Enzymes are proteins Proteins make up most of the cell structure Nucleic Acids (C,H,O,N,P) Long chains that contain instructions for cells to function DNA (in nucleus) RNA (throughout the cell) Water 2/3 of your body Important for reactions Wilting
Diffusion and Osmosis Osmosis- across a membrane (solvent), movement decreases concentration Diffusion- spreading out, high concentration to low concentration
Respiration and Fermentation Respiration Using Oxygen and sugar to produce energy Fermentation Without using oxygen, use sugar to produce energy Occurs in muscle cells, produces lactic acid (muscle burn)