2. Kingdom Monera | Arizona State University

University:
Arizona State University
Course:
BIO 181 | General Biology I
Academic year:

2021
Views:

203

Pages:

1
Author:

Hidalgokr1

2. KINGDOM MONERA It is a kingdom of Prokaryotes. Moneran cells are microscopic without a nucleus and rigid cell wall. . Monerans are important decomposers and mineralisers in the biosphere. Eg : BACTERIA Bacteria were discovered by Leeweenhock (1676). They are omnipresent (present every where) Based on their shape bacteria were devided into four types. (i) Coccus - Spherical bacteriumi (ii) Bacillus - rod shaped bacterium (iii) Spirillum - Long and spirally coiled bacterium (iv) Vibrio - Bacterium with a slight bent cell and appears like, comma. Bacteria are considered as plants due to the presence of rigid cell wall (A cell wall is invariably found in all plant cells). There is no definite nucleus in bacterium. DNA is in the form of circular chromosome. Bacteria are devided into “Gram Positive” and “Gram Negative” types based on “Gram Staining Technique”. The reagent used in this staining is “crystal violet dye”. Those bacteria which take crystal violet dye during gram staining technique are called gram positive, those which do not take are gram negative. ECONOMIC IMPORTANCE OF BACTERIA : Uses : 1. Nitrifying and nitrogen fixing bacteria increase soil fertility 2. Bacteria decompose dead bodies of plants & animals, thus acting as natural scavengers. 3. A number of drugs like streptomycin, terramycin are extracted from the genus streptomyoes. 4. Bacteria are useful for curdling of milk, tanning of leather, curing of tea & tobacco leaves. 5. Many organic compounds & Vit B are manufactured industrially with the help of bac-teria. 6. Bacteria are used to clean water, polluted with oil because these break down hydrocarbons. Harmful effects : They’are responsible for rot of fruits & Vegetables during storage. Plant diseases Human diseases 1. Blight of Paddy . 1. Pneumonia 2. Citrus canker 2. Throat infection 3. Angular leaf spot 3. Whooping cough of cotton 4. Tetanus 4. Tumors in Plants 5. Typhoid 5. Rot: of vegetables 6. Cholera 7. Tuberculosis 8. Leprocy 9. Diphtheria 10. Plague 11. Wound infection 12. Syphilis 4