morphology of bacteria/bacterial morphology .pptx

morphology of bacteria/bacterial morphology

1. MORPHOLOGY OF BACTERIA PRESENTED BY: M.C.KNIRANDA ASSISTANT PROFESSOR SSNSR, SU.

2. CONTENTS INTRODUCTION SIZE OF BACTERIA SHAPE OF BACTERIA ARRANGEMENTS OF BACTERIAL CELLS

3. INTRODUCTION Bacteria is unicellular , free-living , microscopic microorganisms capable of performing all the essential functions of life. They possess both deoxyribonucleic acid (DNA) and Ribonucleic acid (RNA).

4. INTRODUCTION Bacteria are prokaryotic microorganisms that do not contain chloroplasts , but few bacteria have chlorophyll . (Chloroplasts are organelles found in plant cells and some algae that are responsible for photosynthesis and Chlorophyll is a pigment that gives plants and some microorganism their green color ). But some bacteria can perform photosynthesis such as cyanobacteria.

5. INTRODUCTION They occur in water, soil, air, food, and all natural environment. They can survive extremes of temperature , pH, oxygen, and atmospheric pressure.

6. MORPHOLOGY Morphology is the study of the shapes and arrangement of parts of organisms, in order to determine their function, their development, and how they may have been shaped by evolution . The microorganisms being of very small size are usually expressed in micro- m eter ( μ m ) .

7. SIZE OF BACTERIA Bacteria are very small microorganisms which are visible under the microscope. They are having the size range in microns . Most bacteria are  0.2μm (micron) in diameter and 2−8μm (micron) in length .  Bacteria are stained by staining reagents and then visualised under high power of magnification (1000X) of compound microscope. An electron microscope is used for clear visualization of internal structure of bacteria.

8. SHAPE OF BACTERIA On the basis of shape, bacteria are classified as Cocci Bacilli Vibrios Spirilla Spirochetes Actinomycetes Mycoplasma

9. 1. Cocci Cocci are small, spherical or oval cells. In greek ‘ Kokkos ’ means berry. Eg : Streptococci

10. 2. Bacilli They are rod shaped cells . It is derived from greek word “ Bacillus” meaning stick. In some of the bacilli the length of cell may be equal to width. Eg . Bacillus anthracis

11. OTHER EXAMPLES

12. 3. Vibrios They are comma shaped curved rods. Eg : Vibrio cholerae

13. 4. Spirilla They are longer rigid rods with several curves or coils. They have a helical shape and rigid body. Eg . Helicobacter pylori

14. 5. Spirochetes They are slender(slim) and flexuous spiral forms. Eg . Spirochaeta

15. 6. Actinomycetes The Actinomycetes are  a group of unicellular filamentous bacteria ( thin in diameter; resembling a thread)  that form a branching network of filaments and produce spores(cells which acts as a way to defend themselves) Eg : Streptomyces species.

16. 7. Mycoplasma Mycoplasmas are spherical to filamentous cells with no cell walls They occur as round or oval bodies with interlacing filaments. eg. Mycoplasma pneumoniae

17. ARRANGEMENT OF BACTERIAL CELLS Cocci appears as several characteristics arrangement or grouping. Diplococci Streptococci Tetracocci Staphylococci Sarcinae

18. 1. Diplococci Diplococci are any of several spherical bacteria occurring in pairs. Eg : diplococcus pneumoniae .

19. 2. Streptococci It refers to the bacteria's characteristic grouping in chains that resemble a string of beads. Eg : streptococcus lactis .

20. 3. Tetracocci Tetracocci are a spherical bacterium occurring in square groups of four. Eg : Gaffyka tetragena .

21. 4. Staphylococci Staphylococci are any of a group of round bacteria that cause various diseases and that occur especially in irregular clusters . These cells produce bunches of cocci as in grapes. Eg : staphylococcus aureus , staphylococcus albus .

22. 5. Sarcinae Any of several spherical, bacteria having a cuboidal cell arrangement. These cells produces a cuboidal arrangement of group of a eight cells. Eg : Micrococcus tetragena .

23. Arrangement of grouping formed by bacilli species Diplobacilli Streptobacilli

24. DIPLOBACILLI a pair of rod-shaped bacilli that remain joined together end-to-end following division.

25. STREPTOBACILLI any of various bacilli that form in chains .