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STAINING OF CELLS

IN ORder that the cells may be visible under the microscope with all the necessary details   up to a certain magnification, we need to color them with specific dyes that change the transparency of the specimen and blocks the  photons from the light source to penetrating the transparent specimen. That produces a differential  dark and lighted area corresponding to the organelles that has taken  absorbed the stain. The stain is is the compound that is obtained either chemically or can be obtained from natural sources like  haematoxylin is obtained from the plant Caesalpinia  spinosa and there are different types of hematoxylin, like Mayers Hematoxylin, Delafield’s HEmatoxylin etc. However , haematoxylin  cannot be used directly as it is not actually a dye but has to be ripened  (or oxidized to hematin ) by different processes.The section after bluing is counter stained with eosin.

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Biological Classification–THE FIVE KINGDOMS

The Biological world with incredible diversity has prompted man to try to classify them according to similarity or dissimilarity in characters.IT can be traced back to ages of Aristotle and Plato. However ,in later centuries, Carolus Linnaeus founded the 2 KINGDOM HIERARCHICAL CLASSIFICATION, followed by Robert Whittaker in 1968 ,who pointed the 5 KINGDOM CLASSIFICATION. HOWEVER, this was modified to 6 kingdom classification in later years with 3 domains and the following kingdoms– Archaebacteria,Eubacteria, Protista, Fungi, Plantae, Animalia
Video courtesy: BillNyeRutz

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EUKAROTIC CHARACTERISTICS:

• Cells larger than eukaryotes with distinct nucleus, nuclear membrane,
• Chromosome is present as nuclear reticulum
• Membrane bound cellular organelles like mitochondria, Golgi, plastids present
• Ribosomes are usually attached with E.R. cytoplasm with movement.
• Presence of splicing of mechanism
• Ribosome granules are 60S and 40s, jointly 80s
• Mitotic apparatus present
• Multistranded flagella with (9+2)orientation present
• DNA with histone proteins
• Presence of nickase enzyme that cuts mRNA
• Cell reproduction occurs by mitosis and meiosis