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Learn to recognize possible tests for protein and examine various foods for protein.
Principle
While small items and living beings can be magnified by up to 15 times with a magnifying glass, it is necessary to use a light microscope to magnify by 40x to 400x, with particularly powerful microscopes even 1000x.
Benefits
You should observe some basic rules of microscopy so you can make interesting observations as soon as possible.
How small or big are the objects you see under the microscope? The following exercises shall help to illustrate the magnification of the microscope.
In light microscopy, we have to produce slides that are nearly transparent. This is possible by cutting the specimen in very thin sections. Then the light can shine through it and the internal structures will become visible.
The structures of particular components of organisms often do not display sufficient contrasts. In order to attain more contrast, the biologist applies staining techniques. A simple method to rapidly display nuclei in wet mounts consists in staining them with Methyl Green or carmine ...
Biological specimens are subject to alteration and rapidly show signs of decay once they are isolated from a living organism. If a relatively natural condition is to be retained, the proteins of the protoplasm must be turned into a "frozen state" or denatured. This process is ...
To make permanent microscopic slides, the specimens must be fully dehydrated and fixated, be very thin, and naturally sealed free of air. Natural resins such as Canada balm and malinol can be used to accomplish the exclusion of air. These materials solidify after drying up and become ...
The cell wall in plants has an important function: it gives the plant stability by supportive depositions. Animal cells do not need this support function because many animal species possess skeletons. Animal cells are separated from the exterior world only by means of a membrane. In ...
Principle The characteristic feature of almost all plants is their green color. It comes from a pigment which is the catalyst of the most significant biochemical process on earth: photosynthesis. The name of this pigment is chlorophyll. Chlorophyll is not evenly distributed in a plant cell but ...
Principle The fruits and blossoms of many plants possess intensively bright colors. The colorful fruit attracts animals, are devoured by them and the seeds are excreted at other places. This is how the plant is dispersed. Colorful blossoms attract insects that harvest nectar from the ...
Principle The nucleus is recognizable under the light microscope as a circular object. It can be seen even without previous staining. The nucleus is the control center of many cellular processes and harbors the hereditary information. The nucleus contains filamentous structures (chromatin) ...
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