1. Classification of Microorganisms<br />What is microorganisms?<br />Microorganisms also known as microbes. Microorganisms are living things which are so small that they cannot be seen with the naked eye and are only visible under the microscope.<br />Types of MicroorganismsBased on their characteristics ( appearance, shape, size, method of reproduction, nutrition and habitat), microorganisms can be classified into 5 groups:1)Bacteria2)Fungi3)Protozoa4)Virus5)Algae<br />BACTERIA spiralla bacteria cocci bacteria stomach bacteria CharacteristicsBacteria cell structure -Unicellular organisms-They have cell wall made of peptidoglycan -Some have additional slimy capsule outside their cell wall for added protection -Beneath the cell wall is its plasma membrane -Bacteria do not have nuclear membrane-Some bacteria have one or more tail-like structure called 'flagella' which are used for swimming -Some bacteria also have hundreds of hairlike structures known as pilli Shape-Classified according to their shapes -They can be spherical known as cocci, rod-shaped known as bacilli, comma shaped known as vibrios and spiral known as spirilla Size-Diameter ranges from 0.5 -1.0 micrometres-Only visible using a high powered micoscopeMethod of reproduction Sexually by a process called conjugation or Asexually by formation of spores or binary fission NutritionPhotosynthesis, Chemosynthesis, Saprophytic and Parasitic. Bacteria stores food in the form of glycogen granules in its cytoplasm. HabitatCan be found almost everywhere (foods, air, water, soil, on any surfaces (such as table tops), on the outside as well as inside of organisms especially in the intestines). Mode of respiration -Some are aerobic, requiring oxygen to survive-Some are anaerobic, do not need oxygen to survive-Some can live in the presence or absence of oxygen <br />FUNGI Yeast Mucor Mucor on breadCharacteristicsDo not contain the green pigment chlorophyll, so they have to take in nutrients from external. Fungi may be unicellular or multicellular. Size10 - 100 micrometres Method of reproduction Asexually through budding or formation of spores and sexually through conjugation Nutritionparasitism and saprohytism HabitatDark, moist, warm environment ExampleYeast, Mucor/ Mould <br />PROTOZOA Paramecium Amoeba PlasmodiumCharacteristics-Unicellular organisms-Move with the help of cillia which continuously beat against the water in diagonal pattern Method of reproduction Asexually through binary fission or sexually by conjugation Nutrition-Parasitism, saprophytism or autotrophs-Cilia/ cilium (hair like structures) send food to oral groove HabitatSoil, moist area, live in water ( Amoeba) or inside the body of organisms (Plasmodium) ExamplesAmoeba, Plasmodium, Paramecium <br />VIRUS Influenza virus Ebola virus Flu virusCharacteristicsVirus cell structure -smallest microorganisms-do not carry out any characteristics of living things-when outside a cell, it forms a crystaldo not show cell organizationShapeMaybe spherical, polyhedral, rod-shaped or rocket shaped SizeSizes ranges from about 20 - 400 nm in diameter Method of reproduction They can only multiply inside the living cells (host cell) of animals or plants or other microbes. This process harms the host, resulting in a disease.NutritionParasitic Habitatliving cell (host cell) Exampleinfluenza virus (spherical), tobacco mosaic virus (rod-shaped) ALGAE Green Algae (Red Algae) SpirogyraCharacteristics-Simple aquatic plant-No proper roots, stems, leaves or vascular system-contains chlorophyll Size1 - 10000 micrometres Method of reproduction Asexually through binary fission or Sexually by conjugation NutritionPhotosynthesis (most algae have pigments which use the wavelength that penetrate water) HabitatFreshwater and marine (saltwater), soil, bark of trees Examplechlamydomonas (unicellular), spirogyra <br />