Since ancient times, people have been trying to understand how the world around them works. Conducted research, looked inside living things and made conclusions. So accumulated theoretical material, which became the basis for many sciences.
The methods they used came down mainly to observation and experiment. However, it quickly became apparent that the knowledge box would only be half full if you didn’t come up with any more complex, technically advanced devices. Those that will allow you to look inside, reveal the deep mechanisms and consider the features of the device of various objects and living beings.
Methods of study in biology
The main ones include the following:
- Historical method.
- Description.
- Observation.
- Comparison
- Experiment.
Most of them require the intervention of new technical devices that would make it possible to obtain an image in an enlarged multiple size. That is, simply put, different magnifying devices should be used. That is why the need for their construction was obvious.
After all, only in this way were people able to understand how the vital processes of such tiny creatures as protozoa and bacteria, microscopic fungi, lichens and other living organisms occur.
Modern types of devices
Among the variety of technical designs, magnifying devices occupy a special place. Indeed, without them it is difficult to reach the truth and prove a particular theory, especially when it comes to the microworld.
Modern technologies offer the following varieties of such devices:
1. Magnifiers. The structure of magnifying devices of this type is quite simple, therefore, among the analogue ones in action, they appeared first.
2. Microscopes. Today, several varieties can be distinguished:
- optical or light;
- electronic;
- laser;
- X-ray
- scanning probe;
- differential interferon-contrast.
Each finds widespread use not only in the biological sciences, but also in chemistry, physics, space research, genetic engineering, molecular genetics, and so on.
History of magnifying devices
Of course, such a chic variety and perfection of such devices did not come immediately. The most complex constructions, which make it possible to intervene even in wave and particle processes, appeared only in the XX-XXI centuries.
The history of the appearance and development of instruments for increasing is rooted in the depths of centuries. So, if we talk about loops, the excavations showed that the Egyptians had the first such devices long before our era. They were made of rock crystal and so skillfully ground that they gave an increase of up to 1,500 times!
Later they began to make glass lenses and through them examined microscopic objects of interest. This continued until the sixteenth century. Then the great researcher Galileo Galilei constructed his first pipe, which when unfolded resembled a microscope and gave an increase of almost 300 times. This was the progenitor of a modern microscope.
Even later, in the second half of the 17th century, the scientist Tore made small rounded magnifiers. They allowed to consider already at a 1500-fold increase. The big breakthrough in the development of microscopy was the devices designed by Anthony van Levenguk. He produced lots of microscopes that were magnified enough to examine the cell structure and the world of microorganisms.
Since then, magnifying devices (magnifier, microscope) have become an integral part in almost all types of research, both in biological and in other sciences. The modern variety of technical devices owes its existence to people with such names as:
- L.I. Mandelstam.
- D. S. Rozhdestvensky.
- Ernst Abbe.
- R. Richter and others.
Magnification Structure: Magnifier
What do these devices consist of and how do they work? Magnifying devices - a magnifying glass, a microscope - basically have the same structure. The action is based on the use of special glasses - lenses.
The magnifying device magnifier is a convex lens, which is framed in a special outer frame - the frame. The lens itself is a special optical glass with two-sided bulge. The frame can be any:
Magnifying devices such as magnifiers allow you to get images in 25x size. Of course, there are different devices for this indicator. Some loops give a 2-fold increase, and more modernized and perfect ones - even 30.
What are the loops?
The main place to use the magnifier is a biology lesson. Magnifying devices of this kind make it possible to consider small structures of the structure of plants and animals. Different product options may be used.
- Tripod magnifier is a device in which the lens is mounted in a special frame on a tripod for ease of use.
- The device with a pen. With this option, a small convenient handle is built into the frame, with which you can adjust the image quality, bringing the device closer or closer.
- Illuminated magnifier with integrated compass. This is useful for field research in forest taiga. The presence of diode bulbs will allow for observations even at night.
- Pocket magnifier folding and lidding. A very convenient option for continuous carrying.
Combined options between the following are also very common: tripod with backlight, pocket on a cord or with a handle and so on.
Microscope - Magnifying Device
Which device has this item? Today in school, only such magnifying devices are used: a magnifier, a microscope. We have already figured out the structure, work and varieties of the first device. However, to study the deeper processes occurring in the cells, to consider the bacterial composition of water, and so on, the magnifying powers of the magnifier are clearly insufficient.
In this case, the main working tool becomes a microscope, most often ordinary, light or optical. Consider what structural parts are included in its composition.
- The basis of the entire structure is a tripod. It is an element of curved shape to which all other parts of the device are attached. Its broad basis is what the whole microscope as a whole rests on and thanks to which it is stably fixed in a standing position.
- The mirror, which is attached to the tripod from the bottom of the device. It is necessary for capturing sunlight and directing the beam onto a stage. It is fixed on two sides on movable hinges, which facilitates the process of adjusting the light.
- The subject table is a structure that is fixedly mounted on a tripod, most often round or rectangular, equipped with metal fasteners. It is on it that the micropreparation under study is installed, which is clearly fixed on both sides and retains immobility.
- A telescope that ends with an eyepiece on one side and lenses of different magnifications on the other. Also securely attached to a tripod.
- Lenses are located immediately above the stage and are used to focus and enlarge the image. Most often there are three of them, each can be moved and fixed depending on the need.
- The eyepiece is the top of the telescope, and it is designed directly to observe the object.
- The last important part that all magnifying devices of this kind have are macro and microscrews. They serve to adjust the movement of the telescope in order to adjust the best image quality.
Obviously, the structure of the microscope is not too complicated. However, this is typical only for optical models. The average increase that a light microscope can produce is no more than 300 times.
If we talk about modern designs that give an increase of a thousand times, then their structure is much more complicated.
What are microscopes and where are they used?
There are different types of microscopes. The simplest of them, light or optical, is the bulk of the structures for use by students. A magnifier and a microscope are the most acceptable magnifying devices. Grade 6 (biology is a school subject, in the lessons on which these objects are used) implies familiarity with the device, the principles of operation of these devices.
However, schoolchildren should be given an understanding of the types of microscopes that scientists, physicists, chemists, biologists, astronomers and so on work with. There are 5 main ones, they were listed above. Laser and electronic devices allow you to receive images hundreds of thousands of times larger than their true size. This allows you to look inside even the smallest particles and make a lot of discoveries in various fields of science and technology.
Microscope preparation
The lesson "Magnifying devices device" is not the only one in the school study course that concerns working with similar devices. Along with the structure and rules of use, children should lay the foundations of knowledge on the preparation of micropreparations for consideration.
To do this, use the following elements:
- slide;
- coverslip;
- dissecting needle;
- filter paper;
- dropper;
- water.
If it is necessary to consider, for example, the onion peel, then carefully prepare it with a needle and put it in the form of a thin film on a glass slide. It is necessary to place in a drop of water formed in advance with a pipette. On top of the drug is covered with a thin coverslip and firmly pressed. Excess liquid is removed by touching the filter paper. Care must be taken to ensure that there are no air bubbles under the coverslip, otherwise only they will be visible in the microscope.
Factory-made or fixed
In addition to the manufacture of "live" drugs, schools often use ready-made, fixed. They are painted and more informatively saturated, as they are made using special technologies with a high degree of naturalness. Using them, one can master the microstructure of all known structural elements of both animals and plants. In addition, fixed preparations make it possible to study bacteria, microscopic fungi, and other simplest small creatures.
Studying Magnifying Instruments at School
As we noted above, magnifying devices are necessarily studied at the school. Grade 6 is the beginning in the development of the principle of work, the fundamentals of the structure of devices.
Also, it was during this period that the skills to independently install the drug on the stage, to capture light and view the image, are achieved, achieving high definition in tuning. At the next stages of education, children are already confidently using microscopes and magnifiers for a wide variety of studies, since they are fully fluent in the use of devices.
Laboratory work at school using light microscopes.
There are actually quite a lot of them. Each teacher decides what types of work should be done. After all, it all depends on the amount of equipment and its performance. The most common laboratory tests that require the use of magnifying devices are the following:
- Study of the structure of the leaf of a plant.
- Studying the process of transpiration of plants. The structure of the stomata.
- Hyphae of molds.
- Spores of plants, their structure.
- The study of the internal composition of the cell and others.