Laporan Mikroskop

CHAPTER I

INTRODUCTION

A.    Background

In our life, we always find anything with different size. Start from large objects (macro) until small objects (micro). In contrast to the large objects, small object can’t be seen in plain view or naked eyes. One of the example of small object is cell. As the unity of human structural, cell has small size and complex. For seeing the structure of cell, it is so difficult with our limited visual skills.
So we need a tool which can enlarge the size of the object so that it can be seen by our eyes with magnification power until one hundred one. Finally , the scientiest tried to create a tool which can  make easier human activities with all of the weaknesses of eyesight so that a tool was created named Microscope.

Microscope is the main tool which is used to observe small objects. We can observe it and know the structure, for the first time we must know how to use the microscope because we just can observe cell by using microscope which can help us to observe the cell and the structure. It is very helpful know in many sides of our life such as in biology, medice, etc.

Some experiment need the use of microscope to observe the object so that we must know how to use it as well as the rule. If we don’t know about it, we can’t do the experiment well and our observation is unsuccessfuly.. We can feel so difficult to observe the object because we can’t set the light so we can’t find the shadow of the object which is being observed. In addition, we have studied about microscope since elementary school until Senior High School and we will study more about it in University then. So we should be able to use the microscope better than before because the experiment will be more interest if we can use it in a good way. By studying about it, we can be more eficient to observe the smaller thing which can’t be seen by naked eyes.

B.     Purpose

Students skillfully using biological microscope to quickly and safely to see a simple preparation.

C.    Benefits

Able to skillfully using biological microscope to quickly and safely to see a simple preparation.

CHAPTER II

PREVIEW OF LITERATURE

 "Micro" refers to tiny, "scope" refers to view or look at. Microscopes are tools used to enlarge images of small objects so as they can be studied. The compound light microscope is an instrument containing two lenses, which magnifies, and a variety of knobs to resolve (focus) the picture. Because it uses more than one lens, it is sometimes called the compound microscope in addition to being referred to as being a light microscope.  In this lab, we will learn about the proper use and handling of the microscope (Anonymous,2011).

Hooke and van Leewenhoek would not have been able to see the individual structures within human skin cells with their microscopes. Develpments in microscopes technology have given scientists the ability to study cells in greater detail than early scientist ever thought possible (McGraw,2008).

Optical Optical microscope consist of two,there are biological microscope and biological microscope used stereo for seeing transparent. Shining given the observation of a thin object under the natural light or lights. Biological microscope gnerally have eyepiece and objective lens wiyh magnification power as follow:

1.      Objective 4x to 10x eyepiece, 40 magnification

2.      10x objective wit 10x eyepiece, magnification 100x

3.      40x objective with 10x eyepiece, magnification 400x

4.      Objective 100x with 10x eyepiece, magnification 1000x

Objectively the most powerful optical microscope objective 1000x called emertion, because of its use should be emertion oil and how to use it with special using (Tim Pengajar,2012).

Types of Microscope Stand

Even though the outward appearance of the microscope has changed greatly over the last century or so, the purpose of the design has not. The function of the microscope stand has always been to hold the same components -- mirror, condenser, specimen, objective and eyepiece -- on a common optical axis, and to allow finely controlled axial movement between them. The stage supports the specimen to be examined and allows specimen movement in a plane perpendicular to a fixed optical axis.

Three basic designs of microscope stand of the past 150 years.

            In terms of mechanical stability, the end result of this evolutionary process is the modern design in which the limb/base is a rigid fixture and all focusing actions are applied to the stage -- seen on the Olympus microscope (right) above -- a construction much better suited to supporting heavy accessory devices such as zooms, trinoculars and photomicrographic cameras. Recent microscopes incorporate the lamp into the base, enabling the instrument to be moved from one place to another without upsetting the relationship of the components, so the lamp can now be added to the list of components held in alignment by the stand. The detatchable lamp unit seen on the Olympus is now rare, except as an optional extra for less expensive microscopes sold originally with only a mirror. In the four hundred years of its development, the microscope has been adapted to any number of specialized tasks. The illustrations below give some idea of the variety in design. Inverted microscopes have become standard if somewhat specialized laboratory instruments, and the aquarium microscope, whilst no longer manufactured, would be sure to have a modest following if it were offered for sale today (Anonymous,2012).

Microscope allow us to study cells in details. The ones that use visible light to illuminate objects are called light microscope. All the light travels in waves. This property makes light bend when it passes through curved glass lenses. Inside a light microscope, such lenses focus light that passa through a specimen, or bounces off of one,into a magnified image. Photograph of images enlarged with any microscope are called micrographs. Phrase-contrast microscope shine light through specimens. Most cells are nearly transparent,so their internal details may not be visible unless they are first stained , or exposed to dyes that only some cell parts soak up. Parts that abssorb the most dye appear darkest. Staining result in an increase in contrast that allows us to see a greater range of detail. Surface details.can be revealed by reflected light (Cecle Starr,2011).

Compound light microscopes

The modern compound light microscope consists of a series of glass lenses and uses visible light to produce a magnified image. Each lens in the series magnifies the image of the previous lens. For example, when two lenses each individually magnify 10 times, the total magnification would be 100 times (10 _ 10). Scientists often stain cells with dyes to see them better when using a light microscope because cells are so tiny, thin, and translucent. Over the years, scientists have developed various techniques and modifications for light microscopes, but the properties of visible light will always limit resolution with these microscopes. Objects cause light to scatter, which blurs images. The maximum magnification without blurring is around 1000.

Use a Compound Microscope

The parts of a compound microscope are listed and diagrammed in the table below.

1.      Always carry the microscope by holding the arm of the microscope with one hand and supporting the base with the other hand.

2.      Place the microscope on a flat surface. The arm should be positioned toward you.

3.       Look through the eyepieces. Adjust the diaphragm so that the light comes through the opening in the stage.

4.      Place a slide on the stage so that the specimen is in the field of view. Hold it firmly in place by using the stage clips.

5.      Always focus first with the coarse adjustment and the low-power objective lens.

6.      Once the object is in focus on low power, the high-power objective can be used. Use only the fine adjustment to focus the high-power lens.

7.      Store the microscope covered.

Electron microscopes

As they began to study cells, scientists needed greater magnification to see the details of tiny parts of the cell. During the second World War, in the 1940s, they developed the electron microscope. Instead of lenses, the electron microscope uses magnets to aim a beam of electrons at thin slices of cells. This type of electron microscope is called a transmission electron microscope (TEM) because electrons are passed, or transmitted, through a specimen to a fluorescent screen. Thick parts of the specimen absorb more electrons than thin parts, forming a black-andwhite shaded image of the specimen. Transmission electron microscopes can magnify up to 500,000_, but the specimen must be dead, sliced very thin, and stained with heavy metals.

Another type of microscope, the scanning tunneling electron microscope (STM), involves bringing the charged tip of a probe extremely close to the specimen so that the electrons “tunnel” through the small gap between the specimen and the tip. This instrument has enabled scientists to create three-dimensional computer images of objects as small as atoms. Unlike TEM and SEM, STM can be used with live specimens (McGraw,2008).

CHAPTER III

PRACTICUM METHOD

A.    Time and Place

Day / Date :Friday / November 2^nd 2012

Time          :08.10 – 09.10 WITA

Place          :Laboratory of Biology at 3^rd floor of Biology Department of Science and Mathematic Faculty, State University of Makassar

B.     Tools and Materials

1.      Tools provided by the laboratory

a.       Biological Microscope

b.      Toolbox contain :

1)      Glass objects

2)      Glass cover

3)      Petri dish

4)      Tweezers

5)      Pipette hand

2.      Equipment provided by student

a.       New blade

b.      New flannel fabric

c.       Picture books and pencils

3.      Materials provided by the laboratory

a.       Distilled water

b.      Suction filter paper or paper

c.       Cotton

4.      Materials suplied by student

a.       Onion ( Allium cepa)

b.      Leaves of pumpkin (Cucurbita moschata)

c.       Leaf hibiscus ( Hibiscus tiliaceus)

d.      Leaves of Adam Hawa (Rhoe discolor)

C.    Work procedure

1.      Preparing Microscope

a.       Put the microscope on the desk right in front of you.

b.      The microscope was cleaned body with flannel cloth. Never rubbed the lens with the cloth than flannel cloth.

c.       The toolbox was opened, removed containing the stained glass objects and glass cover. Cleaned the glass body with cotton cloth or filter paper.

d.      At the top of your desk there was a microscope, toolbox with contents,guide books and record,materials for practicum. Other than was removed at the other places that have been provided.

2.      Long Set Its Light into Tube

a.       The state of your practice space was considered, where the direction of the brighter light (from the front, left, ort right). Mirror microscope was navigated to the light source. The diaphragma was opened or rotary plate being position holes. Microscope with condensor be positioned close to the preparation table and use a flat mirror. For microscope without condensers used a concave mirror.

b.      The position of the objective lens revolver was adjusted that most shortfacing until a click counter preparations.

c.       Tube was lowered to distance objective by the end of the preparation table or tube down 5-10 mm maximum.

d.      Observed through the eyepiece with the left eye without squinting (it took practice) would appear white circular field. If the brightness is uneven; moving slightly flat mirror until he explained. If glare,narrow aperture or hole in the plate. If the field of view is still obscure means less incoming light, open the aperture and use larger holes on the plate.

e.       The microscope was used to observe the preparation ready.

3.      How to Set Distance Lens with Preparations

a.       The setting of rough hands or fingers macrometer toward masters,tube down,distance objective with a smaller dosage table were rounded,did the opposite. What happened? Microscope tubes other models couldn’t be tilted up and down when macrometer and micrometer rotated.

b.      Replaced glass object containing dosage over the counter preparation preserved in such a way that the material observed in the middle of the hole table, glass object sengkeling flops so as not to shake.

c.       Note the distance objective with glass objects wot exceeding 10 mm. If the distance was large, turn macrometer remedy down tube while viewed from the side glass objects spproaching the end objective to a maximum of 5-10 mm.

d.      Observed through the eyepiece with a hand cranked macrometer by raising tube slowly. Observed the field of view until the shadows. If tube been lifted,half round macrometer shadow appeared yet, meaning missed. Repeated again starting at 3.c; shadow but if there were still vague, then continue turning the micrometer telescope up or down until the clear shadow lines or boundaries.

e.       Checked the eyepiece (magnification how?) And objective (magnification how?), Calculate the megnification you can see the shadow.

f.       If it was observed, the preparation were excluded.

4.      Viewing Magnification

a.       4.f if the obdervation were successful,te shadow that appear will be raised again. Position preparation or the tube not touched .

b.      Rotated the objective lens in such a way that the longer (stronger) perpendicular to preparation table until you hear a click.

c.       Observed turning the micrometer until the shadow of larger ones. Observed shadow there!

d.      If it failed to find a bigger shadow. Raise tube by turning the master finger macrometer opposite direction. Turned back the revolver to get objective lens position is weak (short) to its original position. Without changing the position of preparation, did re-treatment 3.c., 3.d., 3.e., Go to 5.a, 5.b, 5.c, Until it works.

e.       If you would observed the other ingredients,then raise tube. Removed the preparations that have been observed and clear glass objects and glass cover.

f.       Create a new dosage corresponding new step 4.a., Up to 4.f.

g.      At the end of the activity that used a microscope, note the following:

1)      Mixture should not be stored on the counter preparations, must be removed.

2)      Mixture should be cleaned with a wet filter paper or cotton cloth (glass cover slip + objects). Store in a petri dish and put in the gear box.

3)      Clean the microscope body with a flannel cloth. Tube down as low as possible.

4)      Kept the boox microscope.

5)      All the equipment have been cleaned with a cotton cloth used and stored in a box.

6)      Your own equipment, kept themselves to be used for the next activity.

7)      The remaining materials were not used again the trash available.

CHAPTER IV

RESULT AND DISCUSSION

A.    Result

1.      Observation of Microscope

Figure

Note : 1.      Base 2.      Arm 3.      Stage 4.      Clipstage 5.      Mirror 6.      Condensor 7.      Diaphragm 8.      Eyepiece Tube 9.      Revolver 10.  Objective Lens 11.  Eyepiece 12.  Coarse Focus 13.  Fine Focus

2.      Observation of Object

Comparison Figure Onion ( Allium cepa )

Magnification  10x10

Note: a.       Cell b.      Nucleus

Comparison Figure   Leaves of Pumpkin ( Cucurbita moschata )

Magnification  10x10

Note: a.       Trichom

Comparison Figure Leaves of Adam Hawa ( Rhoe discolor )

Magnification  10x10

Note: a.       Stomata

Comparison Figure Leaves of Hibiscus ( Hibiscus tiliaceus)

Magnification  10x10

Note: a.       Trichom

B.     Discussion

Based on the observetion result, we can know that microscope has such components. The function of each component as follow:

1.      Eyepece . is a lens which is near to the observer’s eye. This lens is used to make unreal, stand, and enlarge shadow.

2.      Objetive Lens, it is located near from the object which is being observed.

3.      Tube is use to connect between eyepiece and objective lens.

4.      Coarse focus is use for focussing to the object.

5.      Fine focus function as to make clear the appearance of the object.

6.      Revolver’s function is to set the magnification of objective lens by rotate it.

7.      Mirror is used  to reflect the light.

8.      Diaphragm is used to set the amount of the light.

9.      Condensor is used to collect the light.

10.  Stage is used as the place to put the object which will be observed.

11.  Clip stage is used to clip the object (preparat).

12.  Arm is used as the handle on microscope.

13.  Base is used to support the microscope.

In an experiment, it’s probably if there is some mistakes which influence the observation result. As we observe on the figure we got, there is a component which isn’t found , such as in onion (Allium cepa) we can’t find the nucleus, it is same toward Rhoe discolor we can’t find the stomata.

CHAPTER V

CONCLUSION AND SUGGESTION

A.    Conclussion

Based on the experiment we have done, we can conclude that microscope can observe the small object which can’t be seen by naked eye. Optical microscope has optial part which consist of eyepiece, objective lens, condensor, and mirror. Then, the mechanical parts is consist of revolver, coarse focus, fine focus, and condensor.

B.     Suggestion

1.      Laboratory should prepare well the tools which will be used in experiment.

2.      In doing an experiment we must be careful when use the tools to avoid the accident which probably will happen. We must observe the object carefully and seriously so that we can find a good result.

3.      The assistant should give command so we can miss the mistake while doing the experiment.

 BIBLIOGRAPHY

Anonymous¹.2011.http://www.ekcsk12.org/faculty/jbuckley/lelab/microscopeuse

ab.htm. Accesed on Friday, November 2^nd  2012      

Anonymous².2012.http://www.micrographia.com/tutoria/micbasic/micbpt02/micb

0200.htm. Accesed on Friday, November 2^nd  2012

McGraw,Hill.2008.Biology First Edition.Glencoe : New York.

Starr Cecle,dkk.2011.Biology: Concepts and Applications Eight Edition.Cengage:

Canada.

Tim Pengajar.2012.Guide Book of Basic Biology.UNM : Makassar.