BIOLOGY

THE KINGDOM PROTISTA (PROTOCTISTA), NOTES

THE KINGDOM PROTISTA (PROTOCTISTA) The Kingdom Protista consists of primarily aquatic eukaryotic organisms. All protists are eukaryotic and have evolved from prokaryotes. The other eukaryotic kingdoms, Plantae, Fungi and Animalia evolved from protists in various ways. The protists are unicellular, colonial or simple multicellular organisms. All protists are eukaryotic. Protists are three groups. Animal like protists (Protozoz), plant like protists ...

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CONTROL OF BACTERIA NOTES

CONTROL OF BACTERIA Microorganisms can be controlled by various methods. Physical Methods Many physical methods are applied to prevent bacteria. For example steam, dry heat, gas, filtration and radiation. The process in which we use physical agents to control bacteria/microorganism is known as sterilization process. Sterilization is destruction of all life forms. High Temperature Treatment: High temperature is used in ...

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GROWTH AND REPRODUCTION IN BACTERIA NOTES

GROWTH AND REPRODUCTION OF BACTERIA Bacterial Growth: The increase in number of bacterial cells is called as bacterial growth. This increase in number occurs by asexual reproduction. Asexual Reproduction: In bacteria asexual reproduction occurs by means of binary fission. Binary Fission: The division of a prokaryotic cell into two identical daughter cells is called as binary fission. Following processes occur ...

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NUTRITION OF BACTERIA

NUTRITION IN BACTERIA Why Nutrition / Energy Required? Like other organisms bacteria need nutrition (energy) for their growth, maintenance and reproduction. CLASSIFICATION OF BACTERIA ON THE BASIS OF NUTRITION: On the basis of nutrition bacteria are of two types which are heterotrophic and autotrophic. Heterotrophic Bacteria They cannot synthesize their organic compounds from simple inorganic substances. Most bacteria are heterotrophic. ...

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GRAM STAINING TECHNIQUE OF BACTERIA

Gram Stain Technique on the Basis of Differences in Cell Wall Christian Gram developed the technique of gram stain on the basis of differences in the cell wall. On the basis of this technique bacteria can be divided into two groups: Gram Positive Bacteria: These are the group of bacteria that stained purple. They retain the primary dye due to ...

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BACTERIA SHAPES, SIZE AND CELL STRUCTURE NOTES

KINGDOM PROKARYOTAE (MONERA) Kingdom Prokaryotae / Monera consists of organisms with prokaryotic cells. In Greek the word Pro means “before” and karyon means nucleus. So prokaryotes are cells that do not have true nucleus structure. It mainly includes bacteria. Microbiologists place bacteria in two major groups. Eubacteria (In Greek it means “true bacteria”) Archaeobacteria (In Greek it means “ancient bacteria”). ...

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The Variety of Life

  The word virus is derived from Latin word venome which means poisonous fluid. Virus can be defined as: Non-cellular, submicroscopic infectious agents which contain either RNA or DNA, enclosed by proteinaceous coat, and reproduce only in living cells (obligate intracellular parasites). Viruses use biosyntheticmachinery of the host to make their materials and then transfer to other cells. Study of ...

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Facts About Cells

General Information on Cell The Polysaccharides in bacterial cell wall and cellulose in plant cell wall are carbohydrates. The living content of the cell is called protoplasm. The protoplasm of a eukaryotic cell is divided into nucleus and cytoplasm. The material present in between the plasma membrane and the nuclear membrane is called cytoplasm. Cytoplasm is formed by an aqueous ...

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RIBOSOMES, GOLGI COMPLEX, MITOCHONDRIA, CENTRIOLES

RIBOSOMES Ribosomes were discovered by Palade in 1955. Ribosomes are small, dense organelles, about 20 nm in diameter, present in great numbers in the cell. Most are attached to the surface of RER but they can occur free in the cytoplasm. Ribosomes are made from a combination of rRNA and protein. Eukaryotic ribosomes are composed of an equal quantity of ...

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Endoplasmic Reticulum

ENDOPLASMIC RETICULUM The nuclear envelope joins with the membrane of the endoplasmic reticulum (ER). It is a system of complex network spread throughout the cell. These are present in Eukaryotic cells & are of two types: RER & SER On the outside surface of the RER are ribosomes. The main function of RER is to keep together and transport the ...

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