Lab: Analyzing Two Types Of Microscopes
Lori Stenbeck
Bio K121
June 7, 2012
The Microscope
Introduction:
The purpose of a microscope is to see either enlarge images of small objects and or make seen what is invisible to the naked eye. We have two types of microscopes available in the lab. The dissecting microscope is designed to study objects in three dimensions at low magnification. The compound microscope is used for examining small or thinly sliced sections of objects under magnification that is higher than the dissecting microscope. In this lab we will learn proper use and handling of a microscope.
Dissecting Microscope: Using the dissecting microscope our objective was to learn how to use a dissecting microscope properly to view a penny and a Planaria. Penny:
While observing the penny under 20x magnification I observed that on the tail side a penny Lincoln is sitting in the Lincoln Memorial. While viewing the penny with the naked eye it is nearly impossible to determine that Lincoln is sitting in the Lincoln Memorial. Planaria: …show more content…
In my observations of the Planaria, I noticed that it had a distinct head, eyes and body and it appeared to crawl along the bottom of the bowl.
It looked as if it sometimes glided around the bowl and then sometimes looked like it was inching along sort of like an inch worm. On the basis my observations I could not distinguish a mouth so I believe that their mouths are on the underside of their body, I believe they filter their food and are bottom scavengers. When holding an object in the path of the Planaria it turned around to avoid the object. When touching its head he initially tried to avoid the object and then suctioned to the probe. When touching other parts of the Planaria with the probe its reaction was to curl up into a ball. The touch response was very different when touching the head compared to the rest of the
Planaria.
Compound Microscope: Using the compound microscope our objectives were to learn how to use a microscope, how to compute magnification, observe a letter e and to observe different types of specimen of pond water. Handling a Microscope:
Nothing should touch the microscope lens except special lens paper, used to clean the ocular and objective lenses. The moving parts of a microscope should move smoothly, very little force is required to operate them. Microscopes should always be treated with care.
Magnification:
There is a rule for determining total magnification of a compound microscope. To find out the total magnification, multiply the number of the eye piece and the number of the on the objective magnification. For instance, the total magnification of a low power objective: Eyepiece Magnification (X)Objective Magnification=Total Magnification 10 X 4 = 40X
Letter e:
The image seen through the eyepiece and the actual image on the stage are different. The image is reverted 180 degrees (e→Ә). Also when you focus downward (turn the fine adjustment away from you) it brings the (e) out of focus. When you focus upwards (turn the fine adjustment towards you) it brings the (e) into focus. It would not be practical to attempt to examine thick objects because the proximity of the objective lens to the stage. When you move the slide towards you on the stage the letter appears to be moving away from you as you look through the ocular lens. When you move the slide away from you on the stage the letter appears to be moving towards you as you look through the ocular lens.
Pond Samples:
When viewing the different types of water samples from the pond we observed a couple of different organisms. In the Zooplankton slide I observed a form of Daphnia, I was unable to determine species. In the Utricularia gibba sample we observed what appeared to be a fly, covered in water mold. In the Cabomba caroliniana I observed many different diatoms.
Conclusion:
When handling a microscope, there are two procedures that should be taken carefully. We should start observing at the low-power objective and we should always handle the microscope with great care.
The dissecting microscope is used to observe thicker, three dimensional objects under lower magnification to be able to define things more clearly that can already be seen with the naked eye.
The compound microscope is called this because it contains two lenses. As shown in the (e) images, observed under the light microscope are reversed and inverted. This is because when light passes the lens of the eyepiece, the image gets inverted since those lenses are convex lenses. The specimen that should be viewed under a compound microscope should be thin specimens so that the light can pass through them.
In this lab, I observed not only the external features and functions of the microscope, but also the specimens magnified through the microscope. I remember having a hard time getting a clear image of the specimen. I improved my skills as I continued through the lab.
Bio K121
June 7, 2012
The Microscope
Introduction:
The purpose of a microscope is to see either enlarge images of small objects and or make seen what is invisible to the naked eye. We have two types of microscopes available in the lab. The dissecting microscope is designed to study objects in three dimensions at low magnification. The compound microscope is used for examining small or thinly sliced sections of objects under magnification that is higher than the dissecting microscope. In this lab we will learn proper use and handling of a microscope.
Dissecting Microscope: Using the dissecting microscope our objective was to learn how to use a dissecting microscope properly to view a penny and a Planaria. Penny:
While observing the penny under 20x magnification I observed that on the tail side a penny Lincoln is sitting in the Lincoln Memorial. While viewing the penny with the naked eye it is nearly impossible to determine that Lincoln is sitting in the Lincoln Memorial. Planaria: …show more content…
In my observations of the Planaria, I noticed that it had a distinct head, eyes and body and it appeared to crawl along the bottom of the bowl.
It looked as if it sometimes glided around the bowl and then sometimes looked like it was inching along sort of like an inch worm. On the basis my observations I could not distinguish a mouth so I believe that their mouths are on the underside of their body, I believe they filter their food and are bottom scavengers. When holding an object in the path of the Planaria it turned around to avoid the object. When touching its head he initially tried to avoid the object and then suctioned to the probe. When touching other parts of the Planaria with the probe its reaction was to curl up into a ball. The touch response was very different when touching the head compared to the rest of the
Planaria.
Compound Microscope: Using the compound microscope our objectives were to learn how to use a microscope, how to compute magnification, observe a letter e and to observe different types of specimen of pond water. Handling a Microscope:
Nothing should touch the microscope lens except special lens paper, used to clean the ocular and objective lenses. The moving parts of a microscope should move smoothly, very little force is required to operate them. Microscopes should always be treated with care.
Magnification:
There is a rule for determining total magnification of a compound microscope. To find out the total magnification, multiply the number of the eye piece and the number of the on the objective magnification. For instance, the total magnification of a low power objective: Eyepiece Magnification (X)Objective Magnification=Total Magnification 10 X 4 = 40X
Letter e:
The image seen through the eyepiece and the actual image on the stage are different. The image is reverted 180 degrees (e→Ә). Also when you focus downward (turn the fine adjustment away from you) it brings the (e) out of focus. When you focus upwards (turn the fine adjustment towards you) it brings the (e) into focus. It would not be practical to attempt to examine thick objects because the proximity of the objective lens to the stage. When you move the slide towards you on the stage the letter appears to be moving away from you as you look through the ocular lens. When you move the slide away from you on the stage the letter appears to be moving towards you as you look through the ocular lens.
Pond Samples:
When viewing the different types of water samples from the pond we observed a couple of different organisms. In the Zooplankton slide I observed a form of Daphnia, I was unable to determine species. In the Utricularia gibba sample we observed what appeared to be a fly, covered in water mold. In the Cabomba caroliniana I observed many different diatoms.
Conclusion:
When handling a microscope, there are two procedures that should be taken carefully. We should start observing at the low-power objective and we should always handle the microscope with great care.
The dissecting microscope is used to observe thicker, three dimensional objects under lower magnification to be able to define things more clearly that can already be seen with the naked eye.
The compound microscope is called this because it contains two lenses. As shown in the (e) images, observed under the light microscope are reversed and inverted. This is because when light passes the lens of the eyepiece, the image gets inverted since those lenses are convex lenses. The specimen that should be viewed under a compound microscope should be thin specimens so that the light can pass through them.
In this lab, I observed not only the external features and functions of the microscope, but also the specimens magnified through the microscope. I remember having a hard time getting a clear image of the specimen. I improved my skills as I continued through the lab.