Скачать презентацию Microscopes Compound Light up to X 2 Скачать презентацию Microscopes Compound Light up to X 2

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Microscopes • Compound Light (up to X 2, 000) • Electron (up to X Microscopes • Compound Light (up to X 2, 000) • Electron (up to X 200, 000) • Scanning Electron Microscope (SEM) • Transmission Electron Microscope (TEM)

Chapter 1 • Light Microscopes View cells! – compound light microscope: shines light through Chapter 1 • Light Microscopes View cells! – compound light microscope: shines light through a specimen. -Magnifies up to 2, 000 times. – Magnification is the increase of an object’s apparent size. – Resolution is the power to show details clearly in an image.

Chapter 1 Object Size and Magnifying Power of Microscopes Chapter 1 Object Size and Magnifying Power of Microscopes

Chapter 1 • Electron Microscopes View things smaller than cells! – In an electron Chapter 1 • Electron Microscopes View things smaller than cells! – In an electron microscope, a beam of electrons produces an enlarged image of the specimen. – Electron microscopes provide greater magnification and resolution than light microscopes. – Magnifies up to 200, 000 times.

Chapter 1 • Electron Microscopes – Scanning electron microscopes (SEM) pass a beam of Chapter 1 • Electron Microscopes – Scanning electron microscopes (SEM) pass a beam of electrons over the specimen’s surface for better viewing the external surface of a specimen. Gives a “ 3 D” appearance. – Transmission electron microscopes (TEM) transmit a beam of electrons through a thinly sliced specimen for better viewing the internal structures of a specimen.

Plant cells (Light) Plant cells (Light)

Plant Cell (TEM) Plant Cell (TEM)

Light Microscope 10 X 4 X 10 X 7 8 8 9 13 5 Light Microscope 10 X 4 X 10 X 7 8 8 9 13 5 1. eyepiece 2. body tube 3. fine adjustment knob 4. nosepiece 5. scanning objective 6. low power objective 7. high power objective 8. diaphragm 9. light 10. coarse adjustment 11. arm 12. stage clip 13. base

Functions 1. eyepiece (ocular) – contains a lens capable of 10 X magnification 2. Functions 1. eyepiece (ocular) – contains a lens capable of 10 X magnification 2. body tube-the long tube that holds the eyepiece and connects it to the objectives 3. fine adjustment knob- brings objects slowly into fine focus 4. nosepiece – rotates to change from one lense to another 5. scanning objective - contains a lens capable of 4 X magnification 6. low power objective -- contains a lens capable of 10 X magnification 7. high power objective – contains a lens capable of 40 X magnification 8. diaphragm- controls the amount of light 9. light – directs light into the scope. 10. coarse adjustment knob – brings objects into rapid focus - DO NOT use with high power objective 11. arm-part of the microscope that is held to carry the scope. 12. stage - holds the slide 13. base - supports the microscope, hold to carry.

Using Microscopes List the 6 steps to focus the microscope. 1. Place the prepared Using Microscopes List the 6 steps to focus the microscope. 1. Place the prepared slide on the stage. 2. Move the slide so the beam of light goes through the middle. 3. Turn the coarse adjustment knob so the stage is all the way at the top. 4. Use the scanning 4 X power objective and the coarse adjustment knob, focus down until you see the object. 5. Using the 10 X power objective focus again until you see the object. To Focus on high power: Before you turn in the 40 X objective: make sure the specimen is in the middle of the field of view. 6. Turn in the 40 X objective. Focus only using the fine adjustment knob Turn off light and clean up when finished.

A good example of how to sketch from your microscope A good example of how to sketch from your microscope

Rules for Microscope Drawings 1. All drawings in pencil. 2. use color only when Rules for Microscope Drawings 1. All drawings in pencil. 2. use color only when you see a specific color. 3. Draw a circle to represent the field of vision. 4. Label outside the circle, include magnification and name of what you are looking at. 2. Be neat, label when possible Magnification will always be 40 x, 100 x, or 400 x Magnification = Eyepiece X Lenses 10 4 x, 10 x, or 40 x

Ameba with 40 X lens Ameba 400 X 10 X 40 = 400 Ameba with 40 X lens Ameba 400 X 10 X 40 = 400

Other Rules! 1. Be very careful they are fragile 2. You break, you buy Other Rules! 1. Be very careful they are fragile 2. You break, you buy (and microscopes are expensive) 3. Don’t force anything, if the scope is not working, stop and ask for help

Chapter 1 Standardized Test Prep Multiple Choice, 1. To which of the following does Chapter 1 Standardized Test Prep Multiple Choice, 1. To which of the following does the resolution of a microscope refer? F. its ability to show detail clearly G. its power to scan the surface of an object H. its series of interchangeable objective lenses J. its power to increase an object’s apparent size

Chapter 1 Standardized Test Prep Multiple Choice 1. To which of the following does Chapter 1 Standardized Test Prep Multiple Choice 1. To which of the following does the resolution of a microscope refer? F. its ability to show detail clearly G. its power to scan the surface of an object H. its series of interchangeable objective lenses J. its power to increase an object’s apparent size

Chapter 1 Standardized Test Prep 2. compound light microscope : light : : TEM Chapter 1 Standardized Test Prep 2. compound light microscope : light : : TEM : F. tissues G. electrons H. organelles J. organ systems

Chapter 1 Standardized Test Prep 2. compound light microscope : light : : TEM Chapter 1 Standardized Test Prep 2. compound light microscope : light : : TEM : F. tissues G. electrons H. organelles J. organ systems

10 X 40 X 10 X 40 X

Stage Clips Slide Stage Clips Slide

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. eyepiece 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. eyepiece - where you look through to see the image of your specimen. low power objective -- used for low power magnification of the specimen stage - the specimen is placed on the stage for viewing. glass slide – the specimen is placed on the slide for viewing coverslip –placed over the slide to keep stain and water off of the objectives diaphragm-controls the amount of light going through to the specimen base-supports the microscope, used to carry it fine adjustment knob-small, round knob used to fine tune the focus of your specimen after using the coarse adjustment knob -- used for focusing on low power stage clips-hold the slide in place arm-used when carrying the microscope scanning objective – 4 X objective, used for “scanning” over the slide high power objective -- used for high power magnification of the specimen (the longer objective lens)

Fly (SEM)60 x Fly (SEM)60 x

Chloroplast (TEM) Chloroplast (TEM)

? ? ? SEM ? ? ? SEM

? ? ? SEM ? ? ? SEM

? ? ? SEM ? ? ? SEM

SEM ? ? ? SEM ? ? ?