Note on Some Microscopic Organisms

  • Note
  • Things to remember
  • Videos
  • Exercise
  • Quiz

There are various types of animals in the earth. There are microscopic organisms which cannot be seen by our naked eyes. They can only be seen by the microscope. Bacteria, virus and fungi are the microscopic organisms.

Bacteria

Bacteria are microscopic organisms whose single cells have neither a membrane-enclosed nucleus nor other membrane-enclosed organelles like mitochondria and chloroplasts. Bacteria was discovered by 'Anton Van Leeuwenhoek'. Bacteria can survive on air, water, land, animals and plants. Bacteria are in spherical, rod-shaped, coiled, comma and thread. Some examples of bacteria are coccus, bacillus, helical and vibrio.

Bacteria have no nucleus. Bacteria can be useful and harmful too. Rhizobium helps in nitrogen fixation.

Virus

Virus word is derived from Latin. They are an obligatory parasite and cannot survive outside the living host. The virus has characteristics of both living and non-living beings. Virus are made of Deoxyribonucleic acid (DNA) and Ribonucleic acid (RNA).

Virus divided according to its host:

  1. Plant Viruses: The viruses that affect plants are classified under plant viruses. Example: TMV (Tobacco Mosaic Virus) etc.
  2. Animal Viruses: The viruses that affect animals are classified under animal viruses. Example: Rabies, Rhino Virus etc.
  3. Bacteriophage Virus: The viruses that affect bacteria are classified under bacteriophage. T1, T4 etc.

Fungi

Fungi have no chlorophyll. Some of the fungi are unicellular i.e. yeast and some are multicellular. Fungi can be both parasitic and saprophytic. Fungi gets its food from dead and decayed substances.

Fungi is made up of the collection of filament called hyphae. Fungi reproduce by fragmentation, budding, fission and sporulation. These are all asexual reproduction. Yeast is used to make an alcoholic beverage. The mushroom is also a fungus.

  • Bacteria are microscopic organisms whose single cells have neither a membrane-enclosed nucleus nor other membrane-enclosed organelles like mitochondria and chloroplasts.
  • Virus are made of Deoxyribonucleic acid (DNA) and Ribonucleic acid (RNA).
  • Fungi have no chlorophyll. Some of the fungi are unicellular i.e. yeast and some are multicellular.
  • Fungi reproduce by fragmentation, budding, fission and sporulation.
.

Very Short Questions

Bacteria are microscopic organisms whose single cells have neither a membrane-enclosed nucleus nor other membrane-enclosed organelles like mitochondria and chloroplasts. Bacteria was discovered by 'Anton Van Leeuwenhoek'. Bacteria can survive on air, water, land, animals and plants. Bacteria are in spherical, rod-shaped, coiled, comma and thread. Some examples of bacteria are coccus, bacillus, helical and vibrio. Bacteria have no nucleus. Bacteria can be useful and harmful too. Some bacteria cause diseases like Vibrio which causes cholera and some helps in nitrogen fixation like rhizobium.

Fungi have no chlorophyll. Some of the fungi are unicellular i.e. yeast and some are multicellular. Fungi can be both parasitic and saprophytic. Fungi gets its food from dead and decayed substances.Fungi is made up of a collection of filament called hyphae. Fungi reproduce by fragmentation, budding, fission and sporulation. These are all asexual reproduction. Yeast is used to make an alcoholic beverage. The mushroom is also a fungus.

Virus is the smallest micro organism. As they survive and reproduce only inside other organisms, viruses are called obligatory parasites.

The two characteristics of virus that make it living are:

  1. They have genetic material, DNA and RNA
  2. They reproduce in large numbers while inside the other organisms.

  1. They do not have a cellular structure.
  2. They do not synthesize proteins.

Based on the nature of host cells, there are three types of virus- Animal virus (attacks animals), Plant virus (attacks plants) and Bacteriophages (attacks bacteria).

Full form of:
HIV- Human Immunodeficiency Virus
AIDS- Acquired Immunodeficiency Syndrome
DNA- Deoxyribo Nucleic Acid
RNA- Ribo Nucleic Acid

0%
  • The virus that infects bacteria is known as ______.

    Virus
    Bacteriophages
    Plant virus
    Animal virus
  • Which of the following is living characters of virus?

    Reproduce inside the living cells.


    Made up of nucleic acid i.e. DNA and RNA.


    All of them


    Cause diseases.


  • Who discovered virus?

    Adolf Mendeleev
    Adolf Mayer
    William Mayer
    Adam Mayer
  • What is the full form of TMV?

    Tobacco Mosaic Virus
    Turnip Mosiac Virus
    Tobacco Minor Virus
    Tomato Minor Virus
  • The virus that infects bacteria is known as ______.

    Virus
    Bacteriophages
    Animal virus
    Plant virus
  • Bacteria was discovered by______.

    Berzilius
    Anton Van Leeuwenhoek
    Louis Pasture
    Robert Hook
  • Fungi is made up of collection of filament called ______.

    bud
    stem
    hyphae
    spores
  • ______ is used to make alcoholic beverage.

    Yeast
    Bacteria
    Fungi
    Virus
  • What is the full form of DNA?

    Deoribonucleic acid


    Deoxyribonucleic acid


    Demonribonucleic acid


    Deoxygenated ribonucleic acid


  • What is the full form of RNA?

    Riboxynucleic acid


    Ribonucleic acid


    Ribonucleus acid


    Ribosomenucleic acid


  • You scored /10


    Take test again

DISCUSSIONS ABOUT THIS NOTE

You must login to reply

Forum Time Replies Report
hydra

how fungi infection occur in human body


You must login to reply

Virus is a host specific why


You must login to reply