Railway Science (Biology – Micro Organism)

Virus - small infectious agent that can only replicate inside the cells of another organism. Disease - Chickenpox, Covid - 19, Influenza. Bacteria - microscopic, single celled organism lacking a true nucleus.
Disease - tuberculosis, pneumonia. Fungus - eukaryotic organism that includes microorganisms such as yeast and molds.
Disease - mycosis. Worms - invertebrate animals that have soft, slender and elongated bodies. Disease - Ascariasis, filariasis.

Planaria belong to the phylum Platyhelminthes and are characterized by flat bodies, they have no skeleton, no circulatory or respiratory organs, etc. Liverfluke and Tapeworm also belong to phylum Platyhelminthes. Ascaris - It is the most common type of roundworm infection in humans.

Amoeba: It reproduces by binary fission, where the parent cell divides into two identical daughter cells. Paramecium: It reproduces by conjugation, a sexual process involving two individuals exchanging genetic material. Plasmodium: It reproduces through the process of multiple fission.

Algae are chlorophyll -bearing, simple, thalloid, autotrophic and largely aquatic (both freshwater and marine) organisms. They occur in a variety of other habitats: moist stones, soils and wood. Some of them also occur in association with fungi (lichen) and animals.

Multiple Fission: The process of asexual reproduction in which many daughter cells are produced from the parent cell instead of two daughter cells.
During this process, the nucleus is repeatedly divided to generate a large number of nuclei.
A small amount of cytoplasm is absorbed by each nucleus, and then a membrane is formed around each structure.The dimensions of all the daughter cells formed are similar and identical.
Rhizopus - Reproduce asexually by the formation of the spores. Planaria - Binary Fission. Yeast - Budding.

Bacteria are unicellular organisms belonging to the prokaryotic group where the organisms lack a few organelles and a true nucleus. It can live in high temperatures exceeding 100⁰C like in volcanoes.
It can also withstand extremely cold temperatures and can survive in adverse situations. Types - Cocus (like a berry, are spherical), Bacillus (rod-like) and Spirochete (spiral form).
Viruses need favorable conditions for survival and cannot live in extreme conditions (Hot and cold). Amoeba cannot survive in extreme temperatures. Euglena is a genus of euglenoids.

In this mode a single celled organism reproduces by splitting into two offspring. Budding - A new organism is developed from a small part of the parent's body. Example - Hydra and Yeast.
Vegetative propagation - New plants are grown from the old parts of another plant like roots, shoots and leaves, without involving any reproductive organ. Example - Ginger, Potato.
Spore formation - Spores that grow into new organisms in favorable conditions. Example - Aspergillus, Penicillium.

Agaricus (A genus of mushrooms containing both edible and poisonous species). Multicellular organisms are composed of more than one cell. Example - All the species of plants, animals, fungi.
Paramecium - A genus of eukaryotic, unicellular ciliates, commonly studied as a model organism of the ciliate group. Cyanobacteria (blue-green algae) have chlorophyll similar to green plants and are photosynthetic autotrophs. Mycoplasmas activate macrophages and induce cytokine production and lymphocyte proliferation.