Light Microscopy - Lecture 12 PDF

light microscopy - lecture 12 Created @December 9, 2024 8:31 PM Class its whats the inside that counts Introduction to Microscopes Definition: A microscope is an instrument that allows us to view objects not...

light microscopy - lecture 12 Created @December 9, 2024 8:31 PM Class its whats the inside that counts Introduction to Microscopes Definition: A microscope is an instrument that allows us to view objects not visible to the naked eye. Key Feature: Glass lenses that bend light to enlarge images on the retina. Historical Development of Microscopes Early Use of Lenses Ancient Greece: Archimedes allegedly used a "burning lens" to focus sunlight on ships, though its practicality is doubtful. Romans: Experimented with glass lenses. Used lenses as "burning glasses" for starting fires and cauterizing wounds. Noted magnification effects by moving glass over text or images. Emperor Nero used an emerald to reduce glare during gladiator matches— a precursor to sunglasses. First Vision Aids Reading Stone (800s): Invented by Abbott Furness, a curved glass piece used to magnify text. Eyeglasses (1284): Italian inventor Salvino D’Armate created the first wearable glasses. light microscopy - lecture 12 1  Emergence of Microscopes First Compound Microscope (1595): Invented by Hans and Zacharias Janssen (father and son) in Holland. Consisted of two lenses and an extendable tube, achieving magnifications of 3x to 10x. A foundational design still influencing modern microscopes. Galileo Galilei (1609): Invented his version of the compound microscope, the "occhiolino" (little eye). Also developed the telescope, which brought him fame and controversy. Introduction of the Term "Microscope" (1624): Coined by Giovanni Faber, combining Greek words "micro" (small) and "scopein" (to see). Advancements in Microscopy Antonie van Leeuwenhoek (1632–1723): Crafted high-quality single-lens microscopes, magnifying up to 270x. First to observe and describe bacteria, yeast, red blood cells, and sperm cells. Often called the "Father of Microbiology." Robert Hooke (1635–1703): Developed compound microscopes with added light sources. Published "Micrographia" (1665), documenting microscopic observations. Coined the term "cell" while observing cork. Scientific Breakthroughs and Theories Cell Doctrine (1839): light microscopy - lecture 12 2  Proposed by Theodor Schwann and Matthias Schleiden: Cells are the basic structural and physiological units of living organisms. Cells function as independent entities and building blocks of organisms. Modern Cell Theory (1855): Rudolf Virchow added: "All cells arise from pre-existing cells." Technological and Industrial Developments 19th Century: Improved engineering enabled higher precision in lens crafting and microscope design. Companies like Zeiss in Germany became leaders in the microscope industry, integrating advanced optics and engineering. Key Innovators: Carl Zeiss: Revolutionized microscope manufacturing. Charles Spencer: Produced finely adjustable and precise microscopes. Impact and Legacy Modern microscopes remain based on principles developed by pioneers like Janssen, Galileo, Hooke, and van Leeuwenhoek. Microscopes have enabled critical discoveries in microbiology, medicine, and materials science. Key Takeaways Microscopy's Evolution: From simple lenses to advanced light and fluorescence microscopes. Importance: Central to scientific discovery and understanding of biological structures. light microscopy - lecture 12 3  Collaboration and Controversy: Many key theories and inventions arose from building upon others' work, sometimes without proper acknowledgment. light microscopy - lecture 12 4