Zacharias Jansen and The First Compound Microscope Essay

Concept 6.1 Biologists use microscopes and the tools of biochemistry to study cells 1. The study of cells has been limited by their small size, and so they were not seen and described until 1665, when Robert Hooke first looked at dead cells from an oak tree. His contemporary, Anton van Leeuwenhoek, crafted lenses and with the improvements in optical aids, a new world was opened. Magnification and resolving power limit what can be seen. Explain the difference. Magnification is the ratio of an object’s image size to its real size. Resolution is a measure of the clarity of the image; it is the minimum distance two points can be separated and still be distinguished

2) Electron Microscope (EM) uses a beam of electrons to resolve electrons, better resolving powers than light microscope M:100,000x RP 0,2 nanometer

means "writing or drawing with light." In ancient times, the first uses of a camera were camera obscuras used to form images on walls in darkened room. The image was formed from a pinhole. The brightness and clarity was improved by enlarging that hole and inserting a telescope lens. In 1727, Professor J. Schulze mixes chalk, nitric acid and accidentally creates the first photosensitive compound. Photographer, Nicéphore Niépce, combined the camera obscura and the photosensitive compound. He is credited by most as the inventor of photography and a pioneer of

Another tool that have had a big impact in the science world is the Microscope. A microscope is an optical instrument that uses a lens or combination of lenses to produce a magnified image of small or microscopic objects such as bacteria and cells. One of the most known and historic purposes that the microscope has been used for is during the discovery of penicillin. Dr. Fleming, a bacteriologist, observed that a plate culture of staphylococcus had bee contaminated by a blue green mold. Then tracking and observing the bacteria through a microscope Dr. Fleming was able to observe that the colonies of bacteria next to the mold were being dissolved. Fleming then proceed to grow the mold in pure culture and produced a substance that killed a number of

The illuminating parts of a microscope enable us to see the detail of the subject placed under the microscope. The three main parts that enable us to do this are: the condenser which illuminates the object that is placed under the microscope, the objectives which forms the magnified image, and the eyepiece which enables us to see the magnified

To make the specimen compatible with both forms of advanced microscopy, they sufficiently prepared samples by coupling the specimen with a fluorescence that was also conductive. This technique was accomplished with the FlouroNanogold label, which contains gold nanoparticles covalently bonded to a fluorescence label. That way, the LM worked as well as the EM for the same set of kinetochores that were being studied. The Hec1 protein was stained in this case because this protein naturally delineates the structures to be studied.

A light microscope was set up with the light on a low setting; one large Daphnia was selected and placed in the centre of a cavity slide by using a pipette.

A light microscope was set up with the light on a low setting; one large Daphnia was selected and placed in the centre of a cavity slide by using a pipette.

Another limitation is out of focus light from outside the focal plane reducing image clarity or requiring constant adjusting.  On the other hand, under the right conditions, light microscopy allows for viewing of samples that are still alive.  There are aids such as fluorescent proteins, that can be used to track proteins in real-time in cells though the viewing of where the proteins are may not be very high in resolution, you may see roughly where the protein is in the cell, but will not be able to see the shape of the protein itself. Lastly confocal light microscopy gives moderately higher resolution, and significant enhancements in optical sectioning by limiting out-of-focus light.

to create the first known glass contact lens in 1887. Some say Swiss Physician, Adolf E. Fick and

By using their microscopes, they found that every living plant and animal they examined was made of cells. As microscopes were improved, scientists were able to see smaller and smaller organisms. They found that no matter how large or small the organism was, it was made of cells, leading to cell theory. For example, a German biologist, Theodor Schwann discovered that all plant and animal cells were divided into cells by looking through his microscope. He also discovered that the cell is the basic unit of organization in organisms. Cells can be grouped together to form tissues, which can in turn be grouped together to make an organ. Organs can be grouped together to form a system, which is part of an organism. He was able to use microscopes to see the ways that cells work and help to determine which kind of microorganisms (bacteria) is causing the disease and making people ill. This is particularly valuable in the study of the components of organisms, where physicians are able to overcome a treatment of method to kill disease cells and restore people¡¦s health. The microscope revealed not only the cellular structure of human tissues, but also the organisms that cause diseases. The discovery of cells led scientists to study cells and discover more information about cells; this, allowed scientists to find ways to prevent or cure diseases. The use of microscopes has made many

A small square of a red onion skin (membrane) was observed under a microscope at high power (X40) magnification. The observation showed a large number of onion cells. The structure of one onion cell had a general rectangular shape with a developed cell wall, which gives the rectangular shape to the cell and a cell membrane just beneath it.

Resolution is related to the numerical aperture of the objective lens – the higher the numerical aperture, the better the resolution; and the wavelength of light passing through the lens – the shorter the wavelength, the better the resolution.

NOTE: Answer Question A only if you used a compound light microscope for this experiment.

Most microscopes, including those in schools and laboratories today, are optical microscopes. They use glass lenses to enlarge, or magnify, an image. An optical microscope cannot produce an image of an object smaller than the length of the light wave in use. To see anything smaller than 2,000 angstroms (about 1/250,000 of an inch) a wave of shorter length would