Normal viruses are not capable of protein synthesis or DNA repair on their own, they must rely on the organelles of their host cells for these activities. In addition, mimivirus can make about 150 of its own proteins, and can even repair its own DNA if it gets damaged. Most viruses use either DNA or RNA to carry their genetic information, but mimivirus has both of these nucleic acids. The bases make up 1,260 genes, which makes it as complex as some bacteria. The mimivirus genome contains 1.2 million bases, more than many bacteria. Simply do a search for mimivirus using one of the excellent search engines, such as. There are electron micrographs of mimivirus available on the Internet. An icosahedron has 20 identical equilateral triangles (facets), each subdivided into more equilateral triagular facets. Although most viruses are not visible under an ordinary light microscope, mimivirus appears like a minute spheroid object under a compound microscope using an oil immersion objective (1000x magnification). The length of the helical viral nucleocapsid is determined by the length of the nucleic acid.Ĭubical viruses have the general molecular symmetry of an icosahedron. "Linear" viral capsids have RNA genomes that are encased in a helix of identical protein subunits. It is composed of numerous repeating structural units. The capsid denotes the protein shell that encloses the nucleic acid. The best studied example being the tobacco mosaic virus. Until 1960, the only known examples of viruses with helical symmetry were those of plant viruses. With the exception of a some bacteriophages, viruses fall into two main morphological groups, those with cubical symmetry and those with helical symmetry.
#MICROSCOPE RESOLUTION CALCULATOR CODE#
**html code for abbreviations may not show on all browsers. Remember that the diameter of the field of view changes depending on the power of the objective according to the following table: If 8 plant cells extend across the field of view (2 mm), then each cell is 2/8 or 0.25 mm long. The field of view when using the 10x objective (100x total magnification) is 2 mm. With this microscope you can obtain four different magnifications: 40x, 100x, 400x and 1000x. To calculate the magnification, simply multiply the ocular lens (10x) by the objective lens. The cell is in prophase of mitosis, with distinct chromosomes (chromosome doublets) and a disintegrating nuclear membrane.Ĭompound microscope showing the 10x ocular (eyepiece) and four objectives (4x, 10x, 40x and 100x). Right: Highly magnified view of a cell from the meristematic root tip of an onion showing enlarged nucleus containing 16 chromosomes. The slide was stained with a drop of yellowish-brown gram's iodine.
#MICROSCOPE RESOLUTION CALCULATOR SKIN#
Left: Microscopic view of an onion skin showing several rectangular cells, each with a small, spherical nucleus (red arrow).
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