SNC2D Cell Theory & Microscope PDF

BIOLOGY: Tissues, Organs & Systems of Living Things 1 Cell Theory & The Microscope September 17, 2024 2  Cell Theory 1. All living things are made of one or more cells. Matthias Schleiden (1837) all plants are made of cells...

BIOLOGY: Tissues, Organs & Systems of Living Things 1 Cell Theory & The Microscope September 17, 2024 2  Cell Theory 1. All living things are made of one or more cells. Matthias Schleiden (1837) all plants are made of cells Theodor Schwann(1839) all animals are made of cells 2. The cell is the smallest living unit in all organisms. ◦ nothing smaller than a cell is considered to be alive ◦ i.e. unicellular organisms are the smallest living things protozoa bacteria single-celled organisms smallest living cells 3. All cells arise from the division of other cells What can we see? 6 History Zacharias Janssen and his father Hans of Holland in the 1590’s are credited with creating the first compound microscope Zacharias Janssen 1588-1631 Antonie van Leeuwenhoek, know as the “father” of the microscope Robert Hooke made improvements by working on the lenses Antonie van Leeuwenhoek Robert Hooke 1632-1723 1635-1703 7 Compound Light Microscope Parts of the Microscope Ocular Lens Body Tube Revolving Nose Piece Arm Objective Lenses Aperture Stage Stage Clips Condenser Coarse Adjustment knob Diaphragm Fine Adjustment knob Light Source Base 9 1. Ocular Lens eyepiece contains a lens that magnifies 10x 10 2. Body Tube directs light up to ocular lens 11 3. Arm connects the microscope parts 12 Adjustment Knobs 5. Coarse Focus Knob moves the stage up and down to focus the image 6. Fine Focus Knob moves the stage SLIGHTLY to sharpen the image 7. Revolving Nosepiece holds the objective lenses 14 8. Objective Lenses 2nd set of magnifying lenses 4x, 10x or 40x 15 9. Aperture opening in the stage to let light through 16  10. Stage Clips hold the slide in place 4. stage clip adjustment knobs moves slide around 17 11. Stage supports the slide 18 Diaphragm & Condenser 12. condenser: narrows the beam of light through the slide 13. diaphragm controls the amount of light through the slide Turn to let more light in or to make dimmer. 19 14. Lamp/Light light source sends light up through condenser 20 15. Base supports the microscope 21 Compound Light Microscope 1. ocular lens 2. body tube 3. arm 4. stage clip adjustment knob 5. coarse adjustment knob 6. fine adjustment knob 7. revolving nosepiece 8. objective lens 9. aperture 10. stage clip 11. stage 12. condenser 13. diaphragm 14. light 15. base 22 Compound Light Microscope Microscope Part Function 1. ocular lens eyepiece lens, magnifies 10X 2. body tube directs light into ocular, supports 3. arm support 4. stage clip moves slide around adjustment knob 5. coarse moves stage up and down to adjustment knob focus image Compound Light Microscope Microscope Part Function 6. fine fine focus for most clear adjustment knob image 7. revolving holds objective lenses & nosepiece facilitates changing magnification 8. objective lens further magnifies the image 9. aperture opening to allow light to hit the specimen 10. stage clip holds slide in place Compound Light Microscope Microscope Part Function 11. stage place specimen on it 12. condenser focuses light into a beam 13. diaphragm controls the amount of light hitting the specimen 14. light sends out light rays so specimen is visible 15. base supports microscope  Compound Light Microscope magnification: - the ability of lenses to enlarge the image of a specimen resolution: - the amount of detail visible when viewing a specimen poor resolution = blurred image good resolution = clear, sharp image Field of View diameter of the circle you see written in mm or μm (1mm = 1000 μm) Field of View (FOV) Example: FOV Diameter ≅ ___________ = ___________ Field of View (FOV) Example: 1.3 mm FOV Diameter ≅ ___________ 1300 µm = ___________ Total Magnification TOTAL MAGNIFICATION = OCULAR MAGNIFICATION X OBJECTIVE MAGNIFICATION Total Magnification 4x objective 10x objective 40x objective low power medium power high power Total Magnification Medium Low Power High Power Power Ocular Magnification Objective Magnification Total Magnification Total Magnification Medium Low Power High Power Power Ocular Magnification 10 x 10 x 10 x Objective Magnification 4x 10 x 40 x Total Magnification 40 x 100 x 400 x Estimating Size of an Object with a Microscope 34 Estimating Specimen Size - Consider many specimens will fit across the FOV? Ex: If the FOV is 1.6 mm, how big is 1 cell? How many cells will fit across FOV __________ So each cell is: Diagram Enlargement The specimen size is 0.064mm. You draw this diagram on paper and measure your drawing of the specimen to be 25 mm. What is your drawing enlargement? Using the Microscope Steps 1. Click nosepiece to the lowest power objective (4X) 2. Place the slide on the stage 3. Look into the eyepiece 4. Use the coarse adjustment knob to focus 5. Use stage clips only after having found & centered your slide around an area you want to examine 6. Turn the nosepiece to the higher power objective 7. Do NOT use the coarse focusing knob 8. Use the fine focus knob to sharpen the image Microscope Care Always carry with 2 hands: ◦ one on the arm ◦ and the other on the base Don’t bang it into other objects Make sure base is on a flat surface (only on black benches) Only use lens paper for cleaning Do not force knobs Carefully wrap cord around microscope