Observing Microorganisms Through a Microscope

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "Observing Microorganisms Through a Microscope"

Transcription

1 Chapter 3 Observing Microorganisms Through a Microscope Units of Measurement Microorganisms are measured by metric units unfamiliar to many of us. The micrometer ( m), formerly known as the micron, is equal to (10 6 ) meter. The prefix micro indicates that the unit following should be divided by one million. A nanometer (nm), formerly known as a millimicron (m ) is equal to (10 9 ) meter. Nano tells us that the unit should be divided by one billion. An angstrom (Å) is equal to (10 10 ) meter. Microscopy: The Instruments Compound Light Microscopy The compound light microscope has two sets of lenses: the objective and the ocular. Specimens magnified by the objective lens magnified 100 times, for example are remagnified by the ocular, usually 10 times. Thus, the total magnification is 1000 times. Most microscopes provide magnifications of 100, 400, and A magnification of 2000 times is about the highest obtainable. The specimen is illuminated by visible light from the light source the illuminator that is passed through a condenser, which directs the light rays through the specimen (Figure 3.1a). Resolution, or resolving power, is the ability of a microscope to distinguish between two points. The shorter the wavelength of the illumination, the better the resolution. The white light used in a compound light microscope limits resolving power to about 0.2 m. The lenses closest to the specimen are the objective lenses. For the highest magnification, it is necessary to use oil immersion objectives. Immersion oil has the same refractive index as glass; that is, the relative velocity of light passing through it is the same. Without immersion oil filling the space between the slide bearing the specimen and the objective, the image will be fuzzy, with poor resolution (Figure 3.1b). Darkfield Microscopy Some microorganisms, such as the thin spirochete Treponema pallidum, which causes syphilis, are best seen with darkfield microscopy. In the darkfield microscope, an opaque disk blocks light from entering the objective directly. The light hits only the sides of the specimen, and scattered light enters the objective and reaches the eyes. The specimen appears white against a black background. Phase-Contrast Microscopy Living microorganisms do not show up well in the ordinary compound light microscope. The phasecontrast microscope takes advantage of subtle differences in the refractive index of different parts of 25

2 26 Chapter 3 Ocular lens (eyepiece) Remagnifies the image formed by the objective lens Body tube Transmits the image from the objective lens to the ocular lens Arm Objective lenses Primary lenses that magnify the specimen Stage Holds the microscope slide in position Condenser Focuses light through specimen Line of vision Body tube Objective lenses Specimen Condenser lenses Ocular lens Path of light Prism Diaphragm Controls the amount of light entering the condenser Coarse focusing knob Illuminator Light source Base Illuminator Base with source of illumination Fine focusing knob (a) Principal parts and functions (b) The path of light (bottom to top) FIGURE 3.1 The compound light microscope. the living cell and its surrounding medium. As light is slowed down in portions of differing density, it travels slightly different pathways. When recombined for viewing, the phase differences are seen as areas of differing brightness. The microorganism (and many of its internal structures) is seen in its natural state, alive and unstained. Differential Interference Contrast (DIC) Microscopy Differential interference contrast microscopy is similar to phase-contrast microscopy. It uses differences in refractive indexes but uses two beams of light instead of one. Prisms split each light beam, adding contrasting colors. Compared to standard phase-contrast microscopes, DIC images are more brightly colored, are nearly three-dimensional in appearance, and have higher resolution. Fluorescence Microscopy Certain fluorochrome dyes, which glow with visible light yellow, for example when illuminated by ultraviolet light, can be used to view and identify microorganisms. This is fluorescence; certain substances, when illuminated by a short wavelength, emit light of a longer wavelength. Fluorescence microscopy techniques use a special microscope with ultraviolet light illumination; this light illuminates the specimen but is not permitted to reach the eye. The stained microorganism is highly visible against a dark background in such a microscope. However, the principal use of these dyes and microscopes is in the fluorescent-antibody technique, or immunofluorescence. In this technique, the organisms are allowed to react on a slide with antibodies (highly specific proteins produced by the body s defense

3 Observing Microorganisms Through a Microscope 27 Antibodies Fluorochrome Antibodies combined with fluorochrome Unknown bacterium Cell-surface antigen molecules Bacterial cell with bound antibodies combined with fluorochrome FIGURE 3.2 The principle of immunofluorescence. A type of fluorochrome is combined with antibodies against a specific type of bacterium. When the preparation is added to bacterial cells on a microscope slide, the antibodies attach to the bacterial cells and the cells fluoresce when illuminated with ultraviolet light. system). A fluorescent dye is attached to the antibody. The combination of the antibody, the attached dye, and the microorganism for which the antibody is specific (called an antigen; it stimulates the body to produce these antibodies) allows the microorganism s presence to be detected (Figure 3.2). Because the antibody is specific for a particular microorganism, this is a very useful diagnostic technique. It is often used for diagnosis of syphilis and rabies. Confocal Microscopy One plane of part of a specimen in confocal microscopy is illuminated with a laser, which passes the returned light through an aperture aligned with the illuminated region. Successive planes and regions can be scanned and a clear two-dimensional image obtained. When used with computers, these images can be used to construct three-dimensional images.

4 28 Chapter 3 Electron Microscopy The wavelengths of electrons, which travel in waves much as light does, are only about 1/100,000 as long as those of visible light and therefore have much better resolving power. They can be focused by magnetic lenses in an electron microscope. Transmission Electron Microscopy. In transmission electron microscopy, a beam of electrons is passed through ultrathin sections of the specimen and focused on a fluorescent screen, where it is visible to the eye and can be photographed. Objects are generally magnified 10,000 times to 100,000 times, and structures, called artifacts, may appear as a result of the method of preparation. Salts of heavy metals may be fixed to the specimen (positive staining) to increase the density and make a darker image. If the metals are used on the surrounding field, it is termed negative staining, which is useful for viewing exceptionally small specimens. The technique of shadow casting produces a three-dimensional effect by spraying a heavy metal at an angle, accumulating on one side and leaving a clear area on the other. This also provides an idea of the size and shape. Scanning Electron Microscope. In scanning electron microscopy, the electron beam is directed at the intact specimen from the top, rather than passing through a section, and electrons leaving the surface of the specimen (secondary electrons) are viewed on a televisionlike screen. Spectacular pictures of seemingly three-dimensional, intact organisms are possible. Objects are generally magnified 1000 times to 10,000 times with a resolving power of about 20 nm. Scanning Tunneling and Atomic Force Microscopy Scanning tunneling microscopy uses a thin metal probe that scans a specimen and produces an image of the bumps and depressions of the atoms on the surface of the specimen. In atomic force microscopy a metal-and-diamond probe is moved along the surface of the specimen. The recorded movements yield a three-dimensional image. Preparation of Specimens for Light Microscopy Preparing Smears and Staining Most microorganisms are viewed in stained preparations; that is, they are colored with a dye to make them visible or to emphasize certain structures. A thin film of a microbial suspension, called a smear, is spread on the surface of a slide. Flaming the air-dried smear coagulates the microbial proteins and fixes the microorganisms to the slide so they do not wash off. The smear can then be stained. Basic dyes have a colored ion that is positive, helping them adhere to bacteria, which are slightly negative. Examples of basic dyes are crystal violet, methylene blue, and safranin. Acidic dyes, having a negative color ion, are more attracted to the background than to the negatively charged bacteria; thus, a field of colorless bacteria is presented against a stained background. This is an example of negative staining. An example of an acidic dye is eosin. Simple Stains To visualize shapes and arrangements of cells, a simple stain is usually sufficient. A chemical called a mordant may be added to make the microorganism stain more intensely or increase its size to enhance visibility. Differential Stains The most useful differential stain is the Gram stain, developed by Hans Christian Gram. It divides bacteria into two large groups: gram-positive and gram-negative. In preparing a Gram stain (1) apply a

5 Observing Microorganisms Through a Microscope 29 purple dye, crystal violet, to a heat-fixed smear. This stains all the cells and is called the primary stain. After a water rinse, (2) an iodine mordant is added. When a smear stained in this manner is (3) washed with ethanol or an ethanol-acetone solution, some species of bacteria are decolorized and others are not. If the smear retains the purple dye, the organism is gram-positive. If the alcohol removes the dye, the colorless microorganisms are no longer visible. (4) Safranin, a red dye, is then applied and the decolorized, or gram-negative, bacteria appear pink. Safranin is used here as a counterstain. The Gram stain reflects a basic difference in the cell wall structure of bacteria. It is a first step in identification, and the susceptibility of microorganisms to antibiotics is often related to the Gram reaction. Acid-Fast Stain. Members of the genera Mycobacterium (which includes the causes of tuberculosis and leprosy) and Nocardia possess a cell wall with waxy components. The red dye carbolfuchsin is more soluble in these waxes than in acid-alcohol and is retained by the cell. Therefore, the acid-fast stain, in which carbolfuchsin is applied and gently steamed for several minutes, will stain them red. This dye is held so firmly that the cells are not decolorized by acid-alcohol, which does remove the dye from bacteria that are not acid-fast. A methylene blue counterstain will produce a slide in which acid-fast organisms are red and others are blue. The acid-fast stain is an invaluable aid in the diagnosis of tuberculosis and leprosy. Special Stains A colloidal suspension of dark particles such as India ink or nigrosin can be used as a capsule stain. The capsule will appear around each bacterial cell as a halo from which the India ink carbon particles are excluded. Endospores do not stain by ordinary methods, but the Schaeffer Fulton endospore stain, which uses malachite green as a primary stain and safranin as a counterstain, shows endospores as green within red or pink cells. Flagella are too small to be resolved by light microscopes. In a flagella stain, a mordant can be used to increase the diameter of the flagella until they are visible in a light microscope.

6 30 Chapter 3 Self-Tests In the matching section, there is only one answer to each question; however, the lettered options (a, b, c, etc.) may be used more than once or not at all. I. Matching 1. The electrons pass through a thin section of the specimen. 2. Visible light passes through the specimen; uses separate objective and ocular lenses. 3. Details become visible because of differences in the refractive index of different parts of the cell. 4. Visible light is scattered after striking the specimen, and the specimen is visible against a darkened background. 5. A special microscope using ultraviolet illumination. a. Compound light microscope b. Scanning electron microscope c. Phase-contrast microscope d. Transmission electron microscope e. Fluorescence microscope f. Darkfield microscope 6. The electrons strike the surface of the specimen, and secondary electrons leaving the surface are viewed on a televisionlike screen. II. Matching 1. Pertaining to the relative velocities of light through a substance. 2. Involves the use of antibodies and ultraviolet light. 3. One millionth of a meter. 4. One ten-billionth of a meter. 5. The ability to separate two points in a microscope field. a. Micrometer b. Nanometer c. Ångstrom d. Resolving power e. Refractive index f. Immersion oil g. Immunofluorescence

7 Observing Microorganisms Through a Microscope 31 III. Matching 1. Adhere(s) best to bacteria, which have a negative charge, because the color molecule has a positive charge. 2. Used in diagnosis of tuberculosis. 3. Involve(s) the use of a negative stain made from India ink particles. 4. Schaeffer Fulton stain. 5. Use(s) carbolfuchsin dye. a. Basic dyes b. Acidic dyes c. Gram stain d. Acid-fast stain e. Capsule stain f. Endospore stain 6. Use(s) malachite green. 7. Reflect(s) a basic difference between microbial cell walls; ethanol will not remove stain from bacteria. IV. Matching 1. A microscope that uses laser illumination. 2. Extremely thin microbes, for example, the spirochete Treponema pallidum, are best seen with this type of light microscope. 3. This type of electron microscope yields images with seemingly three-dimensional views of the specimen. a. Confocal b. Phase contrast c. Darkfield d. Transmission e. Scanning 4. Light rays that pass through different portions of the specimen reach the eye with their wave-peaks reinforced or cancelled, making structures of the specimen relatively light or dark. V. Matching 1. Formerly known as a micron. 2. Formerly known as a millimicron. 3. This is of a meter. 4. A billionth of a meter. a. Micrometer b. Nanometer c. Ångstrom d. Millimeter

8 32 Chapter 3 Fill in the Blanks 1. About the highest magnification possible in a compound light microscope is. 2. Immersion oil has about the same refractive index as. 3. Fluorochrome dyes glow with visible light when illuminated by light. 4. Electron wavelengths are only about 1/100,000 as long as visible light and therefore have much resolving power. (better, poorer) 5. Bacteria tend to have a slightly electrical charge. (positive, negative) 6. The thin film of a microbial suspension spread on the surface of a slide is called a. 7. Flaming the slide before applying the stain is called. 8. Transmission electron microscopy permits magnifications as high as about 10,000 times to. 9. In the flagella stain, a is used to increase the diameter of the flagella. 10. Two bacterial genera that are acid-fast are and. 11. A disease for which the acid-fast stain is useful in diagnosis is. 12. In order to see shapes and arrangements of cells, a stain is usually sufficient. 13. dyes have a negative color ion. (acidic, basic)

9 Observing Microorganisms Through a Microscope 33 Label the Art a. Line of vision Path of light Prism Body tube b. Specimen c. Illuminator Base with source of illumination Critical Thinking 1. The equation that describes the resolving power of a microscope is: Resolving power = Wavelength of illumination/2 Numerical Aperture (The numerical aperture of an oil immersion objective is usually 1.30.) If the wavelength of light is 0.52 µm, what is the resolving power of this objective? 2. What type of microscopy would be most appropriate for viewing the following specimens or for the following situations? a. To identify pathogenic bacteria in clinical specimens. b. To view objects smaller than 0.2 m, such as viruses. c. To view heat-fixed, stained bacterial cells. d. To view microorganisms that can t be stained by standard methods, such as Treponema pallidum. e. To view the internal structure of living microorganisms.

10 34 Chapter 3 3. For each of the following specimens or situations, indicate which stain(s) or technique would be most appropriate. a. To detect bacterial capsules and evaluate an organism s virulence. b. To provide the necessary contrast for viewing specimens with a compound light microscope. c. To diagnose infections of Mycobacterium or Nocardia. d. To help determine what antibiotic will be most effective against a certain disease organism. 4. Why do gram-positive cells retain the crystal violet through the alcohol wash of Gram staining, whereas gram-negative cells do not? Answers Matching I. 1. d 2. a 3. c 4. f 5. e 6. b II. 1. e 2. g 3. a 4. c 5. d III. 1. a 2. d 3. e 4. f 5. d 6. f 7. c IV. 1. a 2. c 3. e 4. b V. 1. a 2. b 3. c 4. b Fill in the Blanks glass 3. ultraviolet 4. better 5. negative 6. smear 7. fixing , mordant 10. Mycobacterium; Nocardia 11. tuberculosis or leprosy 12. simple 13. acidic Label the Art a. ocular lens b. objective lenses c. condenser lenses Critical Thinking 1. It would be about 0.2 µm. (The figure for the wavelength of light is for green light, changed from 520 nm.) 2. a. Fluorescence microscopy b. Electron microscopy c. Brightfield microscopy d. Darkfield microscopy e. Phase-contrast microscopy

11 Observing Microorganisms Through a Microscope a. A negative stain using India ink or nigrosin. The India ink (or nigrosin) stains the background but doesn t penetrate the capsule. The capsule shows up as a halo surrounding the cell against a dark background. b. For this purpose a simple stain such as safranin or methylene blue will work fine. c. Acid-fast staining would be appropriate to diagnose infections of Mycobacterium and Nocardia. The red dye, carbolfuchsin, binds strongly to a waxy substance in the cell wall of these organisms but not to other nonacid-fast bacteria. d. The Gram staining reaction is helpful information when choosing an antibiotic, which often shows specificity for either gram-positive or gram-negative bacteria. 4. When iodine is added to a smear after previous staining with crystal violet, they combine to form a complex (CV-I complex) that is larger than the crystal violet molecule that initially entered the cells. The CV-I complex is too large to be washed out of the intact peptidoglycan layer of gram-positive cells. When decolorizing gram-negative cells, the alcohol washes away the outer lipoprotein layer and the crystal violet from the thin layer of peptidoglycan.

12

CHAPTER 3 OBSERVING MICROORGANISMS THROUGH A MICROSCOPE. I. UNITS OF MEASUREMENT - See Table 3.1 in text. + Fig. 3.2

CHAPTER 3 OBSERVING MICROORGANISMS THROUGH A MICROSCOPE. I. UNITS OF MEASUREMENT - See Table 3.1 in text. + Fig. 3.2 CHAPTER 3 OBSERVING MICROORGANISMS THROUGH A MICROSCOPE I. UNITS OF MEASUREMENT - See Table 3.1 in text. + Fig. 3.2 II. MICROSCOPY: THE INSTRUMENTS A. COMPOUND LIGHT MICROSCOPY Figure 3.3 1. Have ocular

More information

Chapter 3: Observing Microorganisms Through a Microscope

Chapter 3: Observing Microorganisms Through a Microscope Chapter 3: Observing Microorganisms Through a Microscope : The technology of making very small things visible to the naked eye. Units of Measurement: The metric system is used to measure microorganisms.

More information

14 The ability of the lenses to distinguish fine detail and structure is called a. Illumination b. Magnification c. Refractive index d.

14 The ability of the lenses to distinguish fine detail and structure is called a. Illumination b. Magnification c. Refractive index d. 1 2 Assume you stain Bacillus by applying malachite green with heat and then counterstain with safranin. Through the microscope, the green structures are a. cell walls. b. capsules. c. endospores. d. flagella.

More information

Observing Microorganisms through a Microscope

Observing Microorganisms through a Microscope Observing Microorganisms through a Microscope Biol 3400 I Microscopy Magnification = how much larger an object is made to appear compared to its real size. Resolving power = The minimum separation distance

More information

Chapter 4. Microscopy, Staining, and Classification. Lecture prepared by Mindy Miller-Kittrell North Carolina State University

Chapter 4. Microscopy, Staining, and Classification. Lecture prepared by Mindy Miller-Kittrell North Carolina State University Chapter 4 Microscopy, Staining, and Classification 2012 Pearson Education Inc. Lecture prepared by Mindy Miller-Kittrell North Carolina State University Microscopy and Staining 2012 Pearson Education Inc.

More information

LAB 3 Bacterial Staining Techniques II I. Differential Stains: Gram Stain and Acid-fast Stain II. Morphological Unknown

LAB 3 Bacterial Staining Techniques II I. Differential Stains: Gram Stain and Acid-fast Stain II. Morphological Unknown LAB 3 Bacterial Staining Techniques II I. Differential Stains: Gram Stain and Acid-fast Stain II. Morphological Unknown I. DIFFERENTIAL STAINS A. Gram Stain B. Acid-fast Stain A. Gram Stain The previous

More information

Lecture 5 Different types of microscopes: UV, dark field, phase contrast, fluorescence and electron microscope.

Lecture 5 Different types of microscopes: UV, dark field, phase contrast, fluorescence and electron microscope. Lecture 5 Different types of microscopes: UV, dark field, phase contrast, fluorescence and electron microscope. Learning objectives: In continuation last class on the principles and basic types of microscopes,

More information

2011 MICROSCOPE REVIEW by Karen L. Lancour RELATIVE SIZE OF MICROBES

2011 MICROSCOPE REVIEW by Karen L. Lancour RELATIVE SIZE OF MICROBES 2011 MICROSCOPE REVIEW by Karen L. Lancour RELATIVE SIZE OF MICROBES 1000 millimeters (mm) = 1 meter (m) 1000 micrometers (µm or mcm) = 1 millimeter (mm) 1000 nanometers (nm) = 1 micrometer (mcm) Size

More information

DIFFERENTIAL STAINING, Part I

DIFFERENTIAL STAINING, Part I DIFFERENTIAL STAINING, Part I Differential staining is a procedure that takes advantage of differences in the physical and chemical properties of different groups of bacteria. It allows us to differentiate

More information

Microscopy. MICROSCOPY Light Electron Tunnelling Atomic Force RESOLVE: => INCREASE CONTRAST BIODIVERSITY I BIOL1051 MAJOR FUNCTIONS OF MICROSCOPES

Microscopy. MICROSCOPY Light Electron Tunnelling Atomic Force RESOLVE: => INCREASE CONTRAST BIODIVERSITY I BIOL1051 MAJOR FUNCTIONS OF MICROSCOPES BIODIVERSITY I BIOL1051 Microscopy Professor Marc C. Lavoie marc.lavoie@cavehill.uwi.edu MAJOR FUNCTIONS OF MICROSCOPES MAGNIFY RESOLVE: => INCREASE CONTRAST Microscopy 1. Eyepieces 2. Diopter adjustment

More information

MICROSCOPY. To demonstrate skill in the proper utilization of a light microscope.

MICROSCOPY. To demonstrate skill in the proper utilization of a light microscope. MICROSCOPY I. OBJECTIVES To demonstrate skill in the proper utilization of a light microscope. To demonstrate skill in the use of ocular and stage micrometers for measurements of cell size. To recognize

More information

Chapter 3. Methods of Culturing Microorganisms. Topics. Different types of media Different types of microscopy

Chapter 3. Methods of Culturing Microorganisms. Topics. Different types of media Different types of microscopy Topics Chapter 3 Methods of Culturing Microorganisms Microscope Methods of Culturing Microorganisms Different types of media Different types of microscopy A single visible colony represents a pure culture

More information

LAB 2: Staining and Streaking Protocols for Simple stain, Gram Stain, Streak Plate Technique and Culture Maintenance

LAB 2: Staining and Streaking Protocols for Simple stain, Gram Stain, Streak Plate Technique and Culture Maintenance LAB 2: Staining and Streaking Protocols for Simple stain, Gram Stain, Streak Plate Technique and Culture Maintenance Lab 2a: INTRODUCTION To Staining Live specimens are difficult to see with the bright

More information

EXPERIMENT #1: MICROSCOPY

EXPERIMENT #1: MICROSCOPY EXPERIMENT #1: MICROSCOPY Brightfield Compound Light Microscope The light microscope is an important tool in the study of microorganisms. The compound light microscope uses visible light to directly illuminate

More information

STAINING OF BACTERIAL CELLS. Objective

STAINING OF BACTERIAL CELLS. Objective STAINING OF BACTERIAL CELLS Objective To learn the techniques of smear preparation, Gram staining, nigrosin staining and correlating the results of Gram staining with KOH test. Introduction Observation

More information

Methods in Histology. Major types of Light Microscopy. Microscopy of living (nonfixed) cells can employ various optical methods:

Methods in Histology. Major types of Light Microscopy. Microscopy of living (nonfixed) cells can employ various optical methods: Methods in Histology Objectives: Understand the uses of the most important types of light microscopes Understand the basic operation and uses of electron microscopes Understand resolution and some basic

More information

Lab 1: The Microscope

Lab 1: The Microscope Lab 1: The Microscope Microscopes are tools that allow us to see objects or detail too small to be seen with the unaided eye. Two aspects of microscopy determine how clearly we can see small objects: magnification

More information

Optics and Image formation

Optics and Image formation Optics and Image formation Pascal Chartrand chercheur-agrégé Département de Biochimie email: p.chartrand@umontreal.ca The Light Microscope Four centuries of history Vibrant current development One of the

More information

SIMPLE STAIN and the GRAM STAIN

SIMPLE STAIN and the GRAM STAIN EXPERIMENT 2 SIMPLE STAIN and the GRAM STAIN In most microbiological staining procedures, the bacteria are first fixed to the slide by the heat fixed smear (Figure 1). In this procedure living, potentially

More information

Microscopy and Cellular Morphology

Microscopy and Cellular Morphology Microscopy and Cellular Morphology As we discussed in class, many organisms on the planet exist as single cells and are referred to as microorganisms bacteria, protozoans, among others. When a single microorganism

More information

Escherichia coli (E. coli) primary stain

Escherichia coli (E. coli) primary stain Lab Exercise #3 - INSTRUCTIONS Identification of Unknown Bacteria Differential Staining and Specialized Bacterial Growth Media Lab Exercise #3 INSTRUCTIONS I. OBJECTIVES: Provide the student with an opportunity

More information

Biophotonics. Basic Microscopy. NPTEL Biophotonics 1

Biophotonics. Basic Microscopy. NPTEL Biophotonics 1 Biophotonics Basic Microscopy NPTEL Biophotonics 1 Overview In this lecture you will learn Elements of a basic microscope Some imaging techniques Keywords: optical microscopy, microscope construction,

More information

Gram Staining. The Most Commonly Used Differential Stain. Advantages:

Gram Staining. The Most Commonly Used Differential Stain. Advantages: Gram Staining The Most Commonly Used Differential Stain Advantages: Can observe size and morphology (like other staining) Can find out additional information about the organism- primarily what type of

More information

TOPIC 2 MICROSCOPES AND CELLS

TOPIC 2 MICROSCOPES AND CELLS Objectives: TOPIC 2 MICROSCOPES AND CELLS 1. Identify the components of the compound light microscope and know the functions of each. Be able to use the microscope to find and to maintain the image of

More information

Care and Use of the Compound Microscope

Care and Use of the Compound Microscope Revised Fall 2011 Care and Use of the Compound Microscope Objectives After completing this lab students should be able to 1. properly clean and carry a compound and dissecting microscope. 2. focus a specimen

More information

Molecular Biology. Lab #2 Growth of E. coli Bacteria

Molecular Biology. Lab #2 Growth of E. coli Bacteria Molecular Biology Name Lab #2 Growth of E. coli Bacteria Escherichia coli (E. coli) is a rod-shaped (bacillus), enteric (gut) bacterium of the family Enterobacteriaceae. It is a normal resident of the

More information

Generating contrast in light microscopy Orion Weiner Principles & Practice of Light Microscopy 2013

Generating contrast in light microscopy Orion Weiner Principles & Practice of Light Microscopy 2013 Generating contrast in light microscopy Orion Weiner Principles & Practice of Light Microscopy 2013 Absorption is not the only way samples interact with light. (polarization, phase shift) Brightfield Phase

More information

BIOLOGY 163 LABORATORY USE OF THE COMPOUND LIGHT MICROSCOPE (Revised Fall 2012)

BIOLOGY 163 LABORATORY USE OF THE COMPOUND LIGHT MICROSCOPE (Revised Fall 2012) BIOLOGY 163 LABORATORY USE OF THE COMPOUND LIGHT MICROSCOPE (Revised Fall 2012) Microscopes in various forms are important tools for biologists. Two types of microscopes that you will use frequently are

More information

Microscopy - Cells. I. Objectives

Microscopy - Cells. I. Objectives Name Microscopy - Cells Date Prior to lab you should: o Know the difference between eukaryotic and prokaryotic cells o Know the major organelles in eukaryotic cells and their basic functions o Know the

More information

Analytical Technologies in Biotechnology Dr. Ashwani K. Sharma Department of Biotechnology Indian Institute of Technology, Roorkee

Analytical Technologies in Biotechnology Dr. Ashwani K. Sharma Department of Biotechnology Indian Institute of Technology, Roorkee Analytical Technologies in Biotechnology Dr. Ashwani K. Sharma Department of Biotechnology Indian Institute of Technology, Roorkee Module 1 Microscopy Lecture - 2 Basic concepts in microscopy 2 In this

More information

Types of Microscope. Microscope and Microscopy. Body of Microscope. Focusing Knobs. Design of Compound Microscope

Types of Microscope. Microscope and Microscopy. Body of Microscope. Focusing Knobs. Design of Compound Microscope Types of Microscope Microscope and Microscopy Anatomy and Physiology Text and Laboratory Workbook, Stephen G. Davenport, Copyright 2006, All Rights Reserved, no part of this publication can be used for

More information

MICROSCOPE TECHNICAL SPECIFICATIONS

MICROSCOPE TECHNICAL SPECIFICATIONS MICROSCOPE TECHNICAL SPECIFICATIONS Abbe Condenser A lens that is specially designed to mount under the stage and which, typically, moves in a vertical direction. An adjustable iris controls the diameter

More information

Microscopes and the Metric System

Microscopes and the Metric System Microscopes and the Metric System BIO162 Fall 2007 Sizes of Microorganisms: -Viruses: 0.01 0.3 um -Bacteria: 1 3 um -Fungi: 3 30 um -Protozoa: 5 1000 um 1 Measuring Microorganisms Ocular Micrometer The

More information

STAINING AND BACTERIAL CELL MORPHOLOGY. To learn the techniques of Gram staining, nigrosin staining and KOH test.

STAINING AND BACTERIAL CELL MORPHOLOGY. To learn the techniques of Gram staining, nigrosin staining and KOH test. STAINING AND BACTERIAL CELL MORPHOLOGY I. OBJECTIVES To learn the technique of smear preparation. To learn the techniques of Gram staining, nigrosin staining and KOH test. To use and relate the Gram stain

More information

Appendix. Cell biologists often need to examine the structure of cells. Principles and Techniques of Microscopy. Optical Principles of Microscopy

Appendix. Cell biologists often need to examine the structure of cells. Principles and Techniques of Microscopy. Optical Principles of Microscopy Appendix Principles and Techniques of Microscopy Cell biologists often need to examine the structure of cells and their components. The microscope is an indispensable tool for this purpose because most

More information

SOURCE: Compound Microscopes

SOURCE:  Compound Microscopes Compound Microscopes mag vs resolution working distance monocular parts care of the microscopes monocular focusing oil immersion measuring field diameter binocular parts binocular focusing Microscopy Exercises

More information

One Saturday evening in 2007, a

One Saturday evening in 2007, a C H A P T E R 3 Tools of the Laboratory Methods of Studying Microorganisms A matter of life or death The meningococcus: A million of these tiny culprits could fit on the head of a pin, yet they can knock

More information

AURAMINE O STAIN. Preanalytical Considerations

AURAMINE O STAIN. Preanalytical Considerations AURAMINE O STAIN Preanalytical Considerations I. PRINCIPLE Acid-fast mycobacteria resist decolorization by acid-alcohol after primary staining owing to the high lipid (mycolic acid) content in their cell

More information

Microscope Lab Introduction to the Microscope Lab Activity

Microscope Lab Introduction to the Microscope Lab Activity Microscope Lab Introduction to the Microscope Lab Activity Wendy Kim 3B 24 Sep 2010 http://www.mainsgate.com/spacebio/modules/gs_resource/ CellDivisionMetaphase.jpeg 1 Introduction Microscope is a tool

More information

Adapted from Biology 15 Laboratory Supplemental Manual: Wrightsman, Ininns and Cannon- Moloznic.

Adapted from Biology 15 Laboratory Supplemental Manual: Wrightsman, Ininns and Cannon- Moloznic. Biology 3B Laboratory Cultural Characteristics of Bacteria Objectives: Describe bacterial structure: colony morphology, cell shape, growth patterns. To distinguish how various growth media will affect

More information

Principles in Light Microscopy. Lecture I. Technical Introduction Lecture II. Applications

Principles in Light Microscopy. Lecture I. Technical Introduction Lecture II. Applications Principles in Light Microscopy Lecture I. Technical Introduction Lecture II. Applications Microscopy Techniques http://www.mcb.ucdavis.edu/faculty-labs/kaplan/ Visible Light Microscopy: http://www.micro.magnet.fsu.edu/index.html

More information

AN INTRODUCTION TO THE COMPOUND MICROSCOPE

AN INTRODUCTION TO THE COMPOUND MICROSCOPE AN INTRODUCTION TO THE COMPOUND MICROSCOPE OBJECTIVE: In this lab you will learn the basic skills needed to stain and mount wet slides. You will also learn about magnification, resolution and the parts

More information

Microscopy and Cytology

Microscopy and Cytology Microscopy and Cytology Item per class per bench 1. DI Water 6 bottles 1 bottle 2. Methylene Blue 6 bottles 1 bottle 3. Iodine 6 bottles 1 bottle 4. Slide boxes with letter e and thread slides 6 boxes

More information

AP Physics B Ch. 23 and Ch. 24 Geometric Optics and Wave Nature of Light

AP Physics B Ch. 23 and Ch. 24 Geometric Optics and Wave Nature of Light AP Physics B Ch. 23 and Ch. 24 Geometric Optics and Wave Nature of Light Name: Period: Date: MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Reflection,

More information

Lab instrumentation. Polarized light microscopy

Lab instrumentation. Polarized light microscopy Polarized light microscopy Polarized light microscopy uses plane-polarized light to analyze structures that are birefringent; unisotropic structures that have two different refractive indices, and capable

More information

Transmission electron microscopy - Wikipedia, the free encyclopedia

Transmission electron microscopy - Wikipedia, the free encyclopedia 1 of 5 10/24/2006 12:55 PM Transmission electron microscopy From Wikipedia, the free encyclopedia (Redirected from Transmission electron microscope) It has been suggested that Selected area diffraction

More information

Imaging Methods: Breath Patterns

Imaging Methods: Breath Patterns Imaging Methods: Breath Patterns Breath / condensation pattern: By cooling a substrate below the condensation temperature H 2 O will condense in different rates on the substrate with the nucleation rate

More information

Spotlight. The Basic Concept of Light Microscope. The incident angle determines the size that we see

Spotlight. The Basic Concept of Light Microscope. The incident angle determines the size that we see Spotlight 理 The Basic Concept of Light Microscope 行 Basic Introduction of Light Microscopy What is the difference between the light microscope and the magnifier? Two kinds of beam path: reflected light

More information

F. Y. B. Sc. Microbiology Paper II: Fundamental Methods in Microbiology

F. Y. B. Sc. Microbiology Paper II: Fundamental Methods in Microbiology F. Y. B. Sc. Microbiology Paper II: Fundamental Methods in Microbiology Chapter 1: Microscopy Q. 12 marks each 1. What is aberration? Explain different types of aberrations. 2. What is microscope? Explain

More information

BIL 151: Mechanisms of Mitosis Proper Use of the Microscope

BIL 151: Mechanisms of Mitosis Proper Use of the Microscope BIL 151: Mechanisms of Mitosis Proper Use of the Microscope You will be using two different types of microscope for this project. Your stereoscope (from the Greek stereo, meaning "solid" and scop, meaning

More information

BUCD. The Boston University Center for Disease Control NEW EMPLOYEE INFORMATION PACKET. Name: ID#: Dear Researcher,

BUCD. The Boston University Center for Disease Control NEW EMPLOYEE INFORMATION PACKET. Name: ID#: Dear Researcher, The Boston University Center for Disease Control NEW EMPLOYEE INFORMATION PACKET Name: ID#: Dear Researcher, Page 2 of 26 Congratulations! You have been accepted into The Boston University Center for Disease

More information

Principles in Light Microscopy. Lecture I. Technical Introduction Lecture II. Applications

Principles in Light Microscopy. Lecture I. Technical Introduction Lecture II. Applications Principles in Light Microscopy Lecture I. Technical Introduction Lecture II. Applications Microscopy Techniques http://www.mcb.ucdavis.edu/faculty-labs/kaplan/ Visible Light Microscopy: http://www.micro.magnet.fsu.edu/index.html

More information

How To Perform DIC Microscopy

How To Perform DIC Microscopy How To Perform DIC Microscopy Technical Support Note #T-3 Date Created: 12/5/03 Category:Techniques Date Modified: 00/00/00 Keywords: DIC, Differential Interference Contrast, Axiovert 200M Introduction

More information

Science In Action 8 Unit C - Light and Optical Systems. 1.1 The Challenge of light

Science In Action 8 Unit C - Light and Optical Systems. 1.1 The Challenge of light 1.1 The Challenge of light 1. Pythagoras' thoughts about light were proven wrong because it was impossible to see A. the light beams B. dark objects C. in the dark D. shiny objects 2. Sir Isaac Newton

More information

PS-7.2 Compare the nature and properties of transverse and longitudinal/compressional mechanical waves.

PS-7.2 Compare the nature and properties of transverse and longitudinal/compressional mechanical waves. PS-7.1 Illustrate ways that the energy of waves is transferred by interaction with matter (including transverse and longitudinal /compressional waves). Understand that a wave is a repeating disturbance

More information

In order to be useful, a smear must have the following qualities:

In order to be useful, a smear must have the following qualities: Smear Preparation and Simple Stain Objectives: Make bacterial smear slides (usually called smears) Distinguish cells on these slides using a simple stain procedure Unstained microbial cells are nearly

More information

ZEISS AXIOSKOP. Microscope s User Manual. Managed by. For information about this instrument, please contact

ZEISS AXIOSKOP. Microscope s User Manual. Managed by. For information about this instrument, please contact ZEISS AXIOSKOP Microscope s User Manual Managed by For information about this instrument, please contact Dr. Alloysius Budi Utama @ ext. 8232 or e-mail budiutama@rice.edu Use of the Axioskop (Zeiss) The

More information

MITOSIS IN ONION ROOT TIP CELLS: AN INTRODUCTION TO LIGHT MICROSCOPY

MITOSIS IN ONION ROOT TIP CELLS: AN INTRODUCTION TO LIGHT MICROSCOPY MITOSIS IN ONION ROOT TIP CELLS: AN INTRODUCTION TO LIGHT MICROSCOPY Adapted from Foundations of Biology I; Lab 6 Introduction to Microscopy Dr. John Robertson, Westminster College Biology Department,

More information

Phase contrast and DIC imaging

Phase contrast and DIC imaging Phase contrast and DIC imaging - Phase contrast - Differential-interferencecontrast (DIC) - Relief-phase contrast Optical microscopy course 25.10.2012 Kirsi Rilla 1 Key terms Contrast = the difference

More information

Viewing Microstructures of Materials using the Optical Microscope

Viewing Microstructures of Materials using the Optical Microscope Viewing Microstructures of Materials using the Optical Microscope Elizabeth Merten and Fumio S. Ohuchi University of Washington Seattle, WA 98195 emerten@u.washington.edu Copyright Edmonds Community College

More information

Exercise 2. The Compound Light Microscope

Exercise 2. The Compound Light Microscope 6 Exercise 2 The Compound Light Microscope INTRODUCTION: Student Learning Objectives: After completing this exercise students will: a. Demonstrate proficient use of the microscope using low, high dry,

More information

Chapter 24. Wave Optics

Chapter 24. Wave Optics Chapter 24 Wave Optics Wave Optics The wave nature of light is needed to explain various phenomena. Interference Diffraction Polarization The particle nature of light was the basis for ray (geometric)

More information

THE COMPOUND MICROSCOPE

THE COMPOUND MICROSCOPE THE COMPOUND MICROSCOPE In microbiology, the microscope plays an important role in allowing us to see tiny objects that are normally invisible to the naked eye. It is essential for students to learn how

More information

Unit 7 Practice Test: Light

Unit 7 Practice Test: Light Unit 7 Practice Test: Light Name: Multiple Guess Identify the letter of the choice that best completes the statement or answers the question. 1. Which portion of the electromagnetic spectrum is used in

More information

Lab 2. Microscopic Observation of Cells

Lab 2. Microscopic Observation of Cells Biology 100 K. Marr (Revised Spring 2010) Lab 2. Microscopic Observation of Cells Prelab Assignment 1. Before coming to lab, read carefully the introduction and procedures of each part of the experiment.

More information

Physics 1653 Final Exam - Review Questions

Physics 1653 Final Exam - Review Questions Chapter 22 Reflection & Refraction Physics 1653 Final Exam - Review Questions 1. The photon energy for light of wavelength 500 nm is approximately A) 1.77 ev B) 3.10 ev C) 6.20 ev D) 2.48 ev E) 5.46 ev

More information

A. COMPOUND LIGHT MICROSCOPE

A. COMPOUND LIGHT MICROSCOPE Period Date LAB. USING MICROSCOPES Throughout the course of the year you will be using two different microscopes. Today you will refresh your knowledge of the compound light microscope and then extend

More information

Microscope Activity. The Lab

Microscope Activity. The Lab Microscope Activity On the following pages you will find a copy of a microscope lab I do with my Bio 100 honors students. There have been a few, but not many modifications in this version I have given

More information

Physical Science Study Guide Unit 7 Wave properties and behaviors, electromagnetic spectrum, Doppler Effect

Physical Science Study Guide Unit 7 Wave properties and behaviors, electromagnetic spectrum, Doppler Effect Objectives: PS-7.1 Physical Science Study Guide Unit 7 Wave properties and behaviors, electromagnetic spectrum, Doppler Effect Illustrate ways that the energy of waves is transferred by interaction with

More information

Microscope Skills Review

Microscope Skills Review AP Biology Objectives Microscope Skills Review Name: After completing this worksheet, you will be able to determine the magnifying power of a microscope. determine the size of the field of view of a microscope.

More information

DETECTION OF BACTERIAL MOTILITY. To demonstrate bacterial motility by microscopic and macroscopic techniques.

DETECTION OF BACTERIAL MOTILITY. To demonstrate bacterial motility by microscopic and macroscopic techniques. DETECTION OF BACTERIAL MOTILITY I. OBJECTIVES To demonstrate bacterial motility by microscopic and macroscopic techniques. To observe flagella in prepared slides stained by specific flagellar stains. II.

More information

Lab 1: The Microscope (10 points)

Lab 1: The Microscope (10 points) Lab 1: The Microscope (10 points) Pierce College Student Outcome: Lab Outcome 1: Review basic microscopy techniques including focusing, illumination, contrast, measuring and review of parts of the microscope

More information

Bacteria. Domain Bacteria. Morphology (cell shape) BIO162 Fall 07. Page Baluch

Bacteria. Domain Bacteria. Morphology (cell shape) BIO162 Fall 07. Page Baluch Bacteria BIO162 Fall 07 Page Baluch Domain Bacteria Differences (cell types, metabolism, etc) between microbes: Are results of evolution from a common ancestor Survival of the fittest for a specific environment

More information

The microscope is an important tool.

The microscope is an important tool. KEY CONCEPT Microscopes allow us to see inside the cell. BEFORE, you learned Some organisms are unicellular and some are multicellular A microscope is necessary to study most cells The cell theory describes

More information

LABORATORY EXERCISES. to accompany MICROBIOLOGY LABORATORY

LABORATORY EXERCISES. to accompany MICROBIOLOGY LABORATORY LABORATORY EXERCISES to accompany MICROBIOLOGY LABORATORY BIO 209 Professor Susan C. Kavanaugh Bluegrass Community & Technical College Spring 2010 INTRODUCTION TO CULTURING, MEDIA, AND ASEPTIC TECHNIQUES

More information

Christian Huygen Light is a wave, not merely a ray As waves propagate each point on the wavefront produces new wavelets. Wave Nature of Light

Christian Huygen Light is a wave, not merely a ray As waves propagate each point on the wavefront produces new wavelets. Wave Nature of Light Wave Nature of Light Christian Huygen Light is a wave, not merely a ray As waves propagate each point on the wavefront produces new wavelets Chapter 24 Wavelength Changes Wavelength of light changes in

More information

Light and Other Radiations

Light and Other Radiations Light and Other Radiations Visible light is a form of electromagnetic radiation. X-rays, infrared, microwaves and gamma rays are other forms of this type of radiation which make up the electromagnetic

More information

Chapter 30 Reflection and Refraction

Chapter 30 Reflection and Refraction Chapter 30 Reflection and Refraction Slide 30-1 Geometrical optics When light or other electromagnetic waves interact with systems much larger than the wavelength, it s a good approximation to Neglect

More information

THE NATURE OF LIGHT AND COLOR

THE NATURE OF LIGHT AND COLOR THE NATURE OF LIGHT AND COLOR THE PHYSICS OF LIGHT Electromagnetic radiation travels through space as electric energy and magnetic energy. At times the energy acts like a wave and at other times it acts

More information

Study Guide for Exam on Light

Study Guide for Exam on Light Name: Class: Date: Study Guide for Exam on Light Multiple Choice Identify the choice that best completes the statement or answers the question. 1. Which portion of the electromagnetic spectrum is used

More information

PART 1 THE MICROSCOPE

PART 1 THE MICROSCOPE Lab 2: INTRODUCTION TO MICROSCOPY (portions of this exercise have been adapted from Introductory Experiments in Cell Biology by K. Fleiszar and B. Wallace, Hunter Textbooks Inc., and Biology in the Laboratory

More information

Microscope Mania. Drawing Specimens

Microscope Mania. Drawing Specimens Microscope Mania Introduction Many people use microscopes daily. Lab technicians, doctors, veterinarians use them to diagnose diseases in people and in animals. Even it s been around for years, the microscope

More information

III. Bacterial Cultivation. Part A: Aseptic Technique. Part B: Culture of Bacteria. Exercise 16: Bacteria and Fungi in the Laboratory Environment

III. Bacterial Cultivation. Part A: Aseptic Technique. Part B: Culture of Bacteria. Exercise 16: Bacteria and Fungi in the Laboratory Environment S E C T I O N Bacterial Cultivation III Part A: Aseptic Technique Exercise 16: Bacteria and Fungi in the Laboratory Environment Part B: Culture of Bacteria Exercise 17: Preparation and Inoculation of Growth

More information

Name Class Date. spectrum. White is not a color, but is a combination of all colors. Black is not a color; it is the absence of all light.

Name Class Date. spectrum. White is not a color, but is a combination of all colors. Black is not a color; it is the absence of all light. Exercises 28.1 The Spectrum (pages 555 556) 1. Isaac Newton was the first person to do a systematic study of color. 2. Circle the letter of each statement that is true about Newton s study of color. a.

More information

List of equipment / apparatus used in microbiology laboratory

List of equipment / apparatus used in microbiology laboratory List of equipment / apparatus used in microbiology laboratory 1. Autoclave 2. Incubator 3. Hot air oven 4. Inoculating loop 5. Vortex mixer / shaker 6. Water bath 7. Heating mantle 8. Hot plate with magnetic

More information

Wave Properties of Electromagnetic Radiation

Wave Properties of Electromagnetic Radiation Wave Properties of Electromagnetic Radiation Two options are available for analytical utility when an analyte interacts with a beam of electromagnetic radiation in an instrument 1. We can monitor the changes

More information

#1 NAME MCB 2004 GENERAL MICROBIOLOGY TEST #1, FEBRUARY 5, 2001

#1 NAME MCB 2004 GENERAL MICROBIOLOGY TEST #1, FEBRUARY 5, 2001 #1 NAME GENERAL MICROBIOLOGY TEST #1, FEBRUARY 5, 2001 IN THIS PART THERE ARE FORTY-FIVE QUESTIONS WORTH TWO POINTS EACH. THERE IS ONLY ONE CORRECT ANSWER FOR EACH QUESTION. PLEASE CIRCLE THE CORRECT LETTER

More information

THE SPEC-20. Table 1: Absorbed Wavelength, Absorbed Color, and Perceived Color Absorbed Wavelength (nm) Absorbed Color

THE SPEC-20. Table 1: Absorbed Wavelength, Absorbed Color, and Perceived Color Absorbed Wavelength (nm) Absorbed Color THE SPEC-20 The electromagnetic spectrum consists of radiation ranging from high energy cosmic and gamma rays to low energy radio waves. Various regions of the electromagnetic spectrum can be used to probe

More information

physics 112N interference and diffraction

physics 112N interference and diffraction physics 112N interference and diffraction the limits of ray optics shadow of the point of a pin physics 112N 2 the limits of ray optics physics 112N 3 the limits of ray optics physics 112N 4 this is how

More information

DIC Imaging using Laser Scanning Microscopes (LSM) on Inverted Stands

DIC Imaging using Laser Scanning Microscopes (LSM) on Inverted Stands DIC Imaging using Laser Scanning Microscopes (LSM) on Inverted Stands Differential Interference Contrast (DIC) imaging is a technique used to increase contrast in brightfield images. In confocal systems,

More information

Lenses and Apertures of A TEM

Lenses and Apertures of A TEM Instructor: Dr. C.Wang EMA 6518 Course Presentation Lenses and Apertures of A TEM Group Member: Anup Kr. Keshri Srikanth Korla Sushma Amruthaluri Venkata Pasumarthi Xudong Chen Outline Electron Optics

More information

Forensic Science: The Basics. Microscopy

Forensic Science: The Basics. Microscopy Forensic Science: The Basics Microscopy Chapter 6 Jay A. Siegel,Ph.D. Power point presentation by Greg Galardi, Peru State College, Peru Nebraska Presentation by Greg Galardi, Peru State College CRC Press,

More information

The Basic Concept of Light Microscope. Taiwan Instrument Co, Ltd Eva Lin

The Basic Concept of Light Microscope. Taiwan Instrument Co, Ltd Eva Lin The Basic Concept of Light Microscope Taiwan Instrument Co, Ltd Eva Lin 1 Today's Outline Different types of light microscopes Upright microscope Inverted microscope Stereomicroscope Basic concepts of

More information

Contents. Fluorescence Microscopy Confocal Microscopy. Nearfield Scanning Optical Microscopy. Electron Microscopy. Atomic Force Microscopy

Contents. Fluorescence Microscopy Confocal Microscopy. Nearfield Scanning Optical Microscopy. Electron Microscopy. Atomic Force Microscopy Material Chemistry Contents Optical Microscopy Historical development Lens aberrations Transmission / Reflection Microscopy Dark-field Microscopy Differential Interference Contrast Microscopy 4 -Microscopy

More information

Bio 321 Lightmicroscopy Electronmicrosopy Image Processing

Bio 321 Lightmicroscopy Electronmicrosopy Image Processing Bio 321 Lightmicroscopy Electronmicrosopy Image Processing Urs Ziegler Center for Microscopy and Image Analysis Light microscopy (Confocal Laser Scanning Microscopy) Light microscopy (Confocal Laser Scanning

More information

Wave Phenomena. Constructive and Destructive Interference

Wave Phenomena. Constructive and Destructive Interference Wave Phenomena INTERFERENCE PATTERN OF WATER WAVES DIFFRACTION OF LIGHT OFF A COMPACT DISC Constructive and Destructive Interference Constructive interference produces maxima, where crests meet crests

More information

Microscopes. Microscope: micro - from Greek meaning small scope from Greek meaning to look or see

Microscopes. Microscope: micro - from Greek meaning small scope from Greek meaning to look or see Microscopes Microscope: micro - from Greek meaning small scope from Greek meaning to look or see By definition a microscope is: 1. An optical instrument consisting of a lens or combination of lenses for

More information

Urinalysis and Body Fluids CRg

Urinalysis and Body Fluids CRg Urinalysis and Body Fluids CRg Unit 2; Session 1 Urine Microscopic Examination The Complete Urinalysis Physical properties already covered Chemical analysis in the next unit Microscopic our current focus

More information

Objectives 450 CHAPTER 10 LIGHT AND OPTICAL SYSTEMS

Objectives 450 CHAPTER 10 LIGHT AND OPTICAL SYSTEMS Objectives Use wave properties to explain interference and diffraction of light. Explain how double slits, a diffraction grating, a single slit, and an aperture produce interference patterns. Use measurements

More information

Compact Disc Technology

Compact Disc Technology Compact Disc Technology The Compact Disc popularly known as CD is the data storage device used to store and retrieve datas encoded in digital format. It is an optical disc made of a special polycarbonate

More information