Microscopy: "Seeing is Believing" David Kuch Lakenheath High School December 2014
Overview Studying cell structure Why is Microscopy Important? Parts of Microscope Use of Microscope Microscopy Experiments
Robert Hooke's vision (1667): “By the help of microscopes, there is nothing so small, as to escape our inquiry” Started as “flea glasses” Could observe details of small objects First use of the word “cells” Valuable biological tool
Why is the microscope important?
Microbiological Advances New ability to view life—improved understanding of the complexity of life Improved understanding of plants Plant anatomy Improved understanding of animals Cells Disease control Medical advances Circulation of blood (1669) Animalcules “aka” bacteria (1676)
Science Emerged and Life Improved “Magnified phenomena that are too small to be seen with the naked eye” Disease control and treatment Genetics Agricultural improvements Veterinary advances
Microscope Part Function How do I use this thing? Eyepiece Lens looked through to see specimen; 10X-15X power; adjustable Body tube Connects the eyepiece to lenses Arm Connects body tube to microscope base Nosepiece Rotating turret with objective lenses; spin to select desired lense Objective lenses Most important microscope part; 3-5 lenses; 4X to 100X power Stage Flat platform where slide is placed Stage clips Metal clips that hold slide in place Coarse adjustment Brings specimen into general focus Fine adjustment Fine tunes focus and increases the detail Illumination Light source (reflective mirrors, low-voltage bulb Iris diaphragm Adjusts light amount on specimen Condenser Gathers and focuses light from the illuminator onto specimen On/off switch turns the illuminator off and on Base supports the microscope and it’s where illuminator is located
Microscope Use Still trying to use this thing? Set your microscope on flat surface and plug in Switch on your microscope's light and adjust diaphragm Rotate nosepiece to the lowest-power objective (10X) Place slide on stage and move specimen under objective Adjust large coarse focus knob until specimen is in focus Adjust small fine focus knob until specimen is focused Adjust diaphragm to get best lighting Scan slide (at low power to get overview of specimen) Rotate nosepiece to 40X and then 100X; refocus carefully https://www.youtube.com/watch?v=SUo2fHZaZCU
Safety Reminders Microscopes are expensive scientific instruments When moving your microscope, always carry it with both hands Careful with objectives Handle them properly/carefully so they will last for many years
Experiment 1: Observing Things Around You
Experiment 2: Gram Stain Procedure: Concept: Result:
Summary What did you learn/improve? Successes and/or Challenges