the weapon for a microbiologist is his microscope

8/13/2019 The Weapon for a Microbiologist is His Microscope

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The weapon for a microbiologist is his microscope. Without a microscope; microbiologists, clinical

researchers, scientists, etc. are lost. The microscope is an important part of a biology lab that helps

one observe specimen that are impossible for the naked human eye to see. Microscopes help magnify

objects 1000x their size and study a biological specimen in detail. The most important tool that helps

in performing various experiments, studies, clinical trails and industrial applications is a microscope.

There are many different types of microscopes and their uses vary according to the type.

Microscopes have played an important part in the field of science. Antonie Philips van Leeuwenhoek

(1632-1723), a Dutch tradesman and scientist should be credited for the invention of this magic

instrument. His crude microscope helped detect invisible animalcules, that is single-celled organisms.

This bought the attention of many scholars towards the field of microbiology. Thus, began the search

for bacteria, virus, fungi, protozoa as well as the recent discovery of DNA. This proves that

microscopes are the most important tools for any scientist in not just the field of life sciences, but also

useful in chemistry, metallurgy and many other scientific fields. In this Buzzle article, we shall learn

about some of the different kinds of microscopes and their uses in short. So, without wasting more

time, let us begin our quest to know more about microscopes and their uses.

Light Microscope

The light microscope is also called the optical microscope. This is also a type of compound microscopethat is used to view microorganisms. The light microscope has different lens that help magnifyimages of the microorganism or specimens loaded on the stage. The eyepieces have a magnificationpower of 10x or 16x. The light microscopes are the types of microscopes used in anatomy andphysiology to observe small animals, plants, metal samples, and microorganisms like bacteria indetail. The light microscope can magnify a specimen about 1500x and used in many areas of biology,anatomy and physiology.

This microscope uses visible light and a system of lenses to magnify the images of the samplesmanifold. The basic type of optical or light microscopes is very simple. However, many complexdesigns have been invented that helps give better resolution images. Thus, light microscopes havebeen divided into two different configurations: simple microscope (one lens) and compound

microscope.

Simple MicroscopeA simple microscope or single lens microscope uses just one lens for magnification of the sample. It isthe original light microscope that is now considered primitive. It uses a single, convex lens that iscommonly observed in the loupe.

Compound Microscope

The most commonly used microscope and the integral part of a school or college lab is the compoundmicroscope. This compound microscope uses two optical parts, called the ocular lens and theobjective lens. The compound microscope can provide about 2000X magnification. Thus, compoundmicroscopes are the types of microscopes used in biology to observe bacterial, algal, protozoa as wellas animal and plant cells.

These microscopes are heavier and larger than simple microscopes. These microscopes collect thelight from the sample with the help of multiple lenses. A separate set of lenses is used to focus thelight into the eye (or camera) to form an image. There are different types of compound microscopes.Some of the basic types are discussed below:

Standard Compound Light MicroscopeThis microscope consists of an eyepiece lens that is in line with the revolving nose piece. The nosepiece holds two or more objective lenses. The light passes from the stage through a hole into thesample. From the sample it passes to the lenses. The images are enlarge 4X, 10X, 40X or 100Xaccording to the objective lenses fitted on the revolving nose piece.


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Inverted MicroscopeAn inverted microscope is actually an upside-down microscope. This involves viewing the sample froman inverted position that helps the viewer see an upright image of the sample. This microscope isuseful for viewing liquid cell cultures. Also helps viewing thick or large specimens clearly.

Stereo MicroscopeDissecting microscope or stereo microscopes have low magnification power. These too are types oflight microscopes that help in observing specimens that are a bit larger in size. It contains two opticalpaths that are at different angles and help the user see the specimen in three dimensions. Thedissecting microscopes are the types of microscopes used in anatomy and physiology for carrying outmicrosurgery, dissection, fine repair, sorting as well as forensics. The advantage of dissectingmicroscope is that it can be used on living samples but it has a low magnification power.

Metallurgical MicroscopeA metallurgical microscope is a microscope used to observe metal, plastic, ceramic as well as other

material samples. They help in observing the surface structure, metal fatigue, etc.

UV MicroscopeA UV microscope uses UV light to produce an image that is twice the resolution seen in visible light

microscopy. Mercury arc or xenon burner is used as the source of UV light. As UV light is harmful tohuman eye, a digital sensor or photographic film is produce to help observe the images.

Fluorescence MicroscopeFluorescence microscope uses high-energy, short-wavelenght light that excites the electrons ofcertain molecules present within the sample. This causes the electrons to shift into a higher orbit andwhen they come back to their original energy levels, they emit low energy, long wavelength light.This light is within the visible spectrum that helps in formation of an image.

Digital MicroscopeA digital microscope uses optical lenses as well as CCD/ CMOS sensors. It provides a 1000xmagnification power. It is used to achieve high quality recorded images of the specimen. Thecommonly used digital microscope has a 15 inch monitor and 2 million pixel camera. The digital CCDcamera is attached to the microscope that is in turn connected to an LCD monitor or computer.

Apart from these light or optical microscopes, there are other microscopes that are categorized basedon the lighting techniques. Some of these microscopes are mentioned below:

Dark-field MicroscopeDark-field microscope is used to observe live spirochetes. This microscope uses a special condenserlens that helps scattering light. This causes it to reflect the light off the specimen at an angle. Theresult is such that any light object is seen on a dark background.

Phase Contrast MicroscopeThe phase contrast microscope uses special condensers that help in throwing the light out of phase.This helps the light pass through the object at different speeds. The phase contrast microscope is oneof the types of microscopes used in biology to view unstained specimens. It is one of the types ofmicroscopes used to study cells and cell parts like mitochondria, lysosomes, Golgi bodies using a

phase contrast microscope.

Electron Microscope

The electron microscope (EM) is one of the most advanced microscopes used today. This microscopeis powered by a beam of electrons with very short wavelengths. These electrons strike objects thatcome in its path and helps increase the resolution of the microscope. The electron microscope is one


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of the types of microscopes used to study cells like tiny viral cells as well as larger molecules. Thereare different types of electron microscopes that are explained below:

Transmission Electron MicroscopeThe transmission electron microscope (TEM) is used to study cells. Ultrathin slices of microorganismslike viruses are placed on a wire grid. Then, these cells are stained with gold or palladium and then

used to observe under a transmission electron microscope. The electron beam is deflected on thedensely coated parts of the cells and the image is observed on dark and light background.

Scanning Electron MicroscopeScanning electron microscope (SEM) is also a type of electron microscope with lower magnificationpower than a transmission electron microscope. However, this microscope helps in viewing three-dimensional images of microorganisms and other specimens. Gold and palladium is used to stain thespecimens mounted on a scanning electron microscope.

Reflection Electron MicroscopeReflection electron microscope (REM) uses an electron bean that is incident on a surface. However,instead of following the principles of TEM or SEM, it detects the elastically scattered electrons.

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the weapon for a microbiologist is his microscope

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